125. The Driver's
Seating
The deluxe fixed seating of a Freebody launch.
The box on the bottom houses the battery, and the slide and swivel are separated by a platform.
The toggle clasp.
The deluxe fixed seating of a Freebody launch.
Having
decided already on the basic mechanism of the seat, I now only have to
put it all together. To recapitulate, the seat will be mounted on a box
which will house batteries. It will have both a swivel and a slide, so
that it can be slid back, away from the steering wheel, and be rotated
to face the rear seat for meals, etc. The base will have to be fixed to
the sole, and will have to be able to be opened to gain access to the
batteries.
There are combination slides and swivels, but they place the slide on top of the swivel. Hence, when the seat is slid back and swivelled, its arc of rotation is actually greater than before, because its centre is on the box, not the seat. I need the circumference to be less, so I have to have my slide under the swivel. That means that I have to use separate ones. The slide is a simple device which bolts directly to the box top, and a forward projecting handle releases the catch to allow the sliding action. There are nine achievable catch positions. The swivel also has a projecting handle, and has twelve catch positions.
I had hoped that the swivel may be able to be connected directly to the slide, but the slide length is 315 mm. and the swivel is only 150 mm., so an interspersing platform will be necessary which will be attached to both.
This is a working sketch of the set up:
There are combination slides and swivels, but they place the slide on top of the swivel. Hence, when the seat is slid back and swivelled, its arc of rotation is actually greater than before, because its centre is on the box, not the seat. I need the circumference to be less, so I have to have my slide under the swivel. That means that I have to use separate ones. The slide is a simple device which bolts directly to the box top, and a forward projecting handle releases the catch to allow the sliding action. There are nine achievable catch positions. The swivel also has a projecting handle, and has twelve catch positions.
I had hoped that the swivel may be able to be connected directly to the slide, but the slide length is 315 mm. and the swivel is only 150 mm., so an interspersing platform will be necessary which will be attached to both.
This is a working sketch of the set up:
The box on the bottom houses the battery, and the slide and swivel are separated by a platform.
With the
slide bolted to the box, its handle will permanently point
forwards. Once the seat is swivelled, the slide handle will be
difficult
to reach, but the swivel handle can be arranged either to move with the
seat, or stay in a fixed position relative to the box. It is obviously
desirable to have it accessible in all positions, so it has to move
with the seat.
In order to hide some of the ugly mechanisms involved here, two pelmet-like structures are needed: one will be attached to the box and point upwards, like a tray, with an aperture for the projection of the slide handle at the front. The other will be attached to the seat, and hang downwards, with an aperture for the projection of the swivel handle. Ideally, they should therefore be circular so that their relative rotation does not reveal any of the inside of the constructions, but to build a circle big enough not to obstruct any of the seat's movements would defeat the purpose of the mechanism, in that it would stick out into otherwise useful space.
The compromise then is to come up with something which looks acceptable when the seat is facing forwards or backwards, but not to worry too much about the intermediate positions. As can be seen from the sketch, the tray only has to be big enough to contain the movements of the platform backwards and forwards. The pelmet or skirt hanging down from the seat has to be big enough to cover the swivel, but its position vis à vis the platform will not change in a forward or backward direction; the seat is fixed to the swivel, which is fixed to the platform. The solution is to allow the platform to form the middle of a sandwich. When the seat is right back the platform might become visible in the gap between skirt and tray, otherwise it will be inside the mechanism and invisible. The slide and swivel will both be obscured by the platform, tray and skirt. It follows that the platform should be as thin as is practical. 9 mm. of edge-banded ply should be perfectly adequate.
It will be necessary to be able to get to the batteries, so the top of the box will have to be openable. That will be achieved by hinging it at the back, and fastening it at the front. A simple toggle clasp will suffice to fasten it, but there will have to be something solid on the front wall of the box, so that the toggle clasp can be screwed to it.
In order to hide some of the ugly mechanisms involved here, two pelmet-like structures are needed: one will be attached to the box and point upwards, like a tray, with an aperture for the projection of the slide handle at the front. The other will be attached to the seat, and hang downwards, with an aperture for the projection of the swivel handle. Ideally, they should therefore be circular so that their relative rotation does not reveal any of the inside of the constructions, but to build a circle big enough not to obstruct any of the seat's movements would defeat the purpose of the mechanism, in that it would stick out into otherwise useful space.
The compromise then is to come up with something which looks acceptable when the seat is facing forwards or backwards, but not to worry too much about the intermediate positions. As can be seen from the sketch, the tray only has to be big enough to contain the movements of the platform backwards and forwards. The pelmet or skirt hanging down from the seat has to be big enough to cover the swivel, but its position vis à vis the platform will not change in a forward or backward direction; the seat is fixed to the swivel, which is fixed to the platform. The solution is to allow the platform to form the middle of a sandwich. When the seat is right back the platform might become visible in the gap between skirt and tray, otherwise it will be inside the mechanism and invisible. The slide and swivel will both be obscured by the platform, tray and skirt. It follows that the platform should be as thin as is practical. 9 mm. of edge-banded ply should be perfectly adequate.
It will be necessary to be able to get to the batteries, so the top of the box will have to be openable. That will be achieved by hinging it at the back, and fastening it at the front. A simple toggle clasp will suffice to fasten it, but there will have to be something solid on the front wall of the box, so that the toggle clasp can be screwed to it.
The toggle clasp.
The frame of the box will,
therefore, have to have full length rails, enclosing the stiles, rather
than the other way around, so that the top rail can be split
horizontally for opening. The seat slide will bolt to the box top,
which will be housed within the perimeter of the upper half of the top
rails, but not right at the top. This way, the top rails themselves
will form the tray which hides the slide.
The batteries I have planned to use are 333 mm. x 172 mm., so a box with an inside dimension of 350 mm. x 350 mm. would suffice to hold two of them upright, including any hold down straps and buckles. The battery height is 235 mm.
Resorting to the desk chair which I used before, to gauge the approximate dimensions required, I can now take some accurate readings of the space involved. The front of the seat comes to about the middle of the glovebox apertures, and the distance athwartships between them is 1260 mm. The desk chair seat is 470 mm. across and 450 mm. deep. When it is centred behind the steering wheel the distance between the seat front and the cockpit lagging is 100 mm.
The batteries I have planned to use are 333 mm. x 172 mm., so a box with an inside dimension of 350 mm. x 350 mm. would suffice to hold two of them upright, including any hold down straps and buckles. The battery height is 235 mm.
Resorting to the desk chair which I used before, to gauge the approximate dimensions required, I can now take some accurate readings of the space involved. The front of the seat comes to about the middle of the glovebox apertures, and the distance athwartships between them is 1260 mm. The desk chair seat is 470 mm. across and 450 mm. deep. When it is centred behind the steering wheel the distance between the seat front and the cockpit lagging is 100 mm.
At a comfortable seating
distance behind the wheel, the front of the seat does not come to lie
over the back of the central, removable sole section, above the shaft
seal. That is a good thing, because this section must be free of
obstruction, and could not have the seat base sitting on top of it.
With the seat back as upright as this one is, there is room for it to
rotate and not hit the wheel, but the back on any driving seat would be
a little more inclined, and would, therefore, need to be able to be
slid back before rotation.
Although there is just adequate room for squeezing between the two front seats in these dimensions, (it actually allows 120 mm. between them), it is not generous, and is nothing like as generous as the Freebody launch as seen below, left.
In all other respects I find the
Freebody design to be the gold standard, but in the matter of front
seating we have to depart. The front seats look too narrow to me, and I
do not think that the outward flare of the seat backs makes up for
that. Nor do I think it is necessary to have such a broad space between
the seats. The use of that gap is only occasional, and I would rather
sacrifice a little passage space for more seating comfort.
Furthermore, as my seats will rotate, it will be important for them to be able to pass one another on the diagonal, so to speak. In other words, when the seat is at 45° to the midline, its most protrusive part should not bump into the other seat. That does not mean that it cannot cross the midline, as the two seats do not have to be rotated simultaneously, but it does limit their proximity to each other.
A good compromise is to reduce the seat width from 470 mm. to 420 mm. which is still comfortable, and which gives a passage of 170 mm. between them. That way, the distance between the midline and the seat is 85mm., just more than is required for the seats to rotate.
The gap between the boards in this mock-up is 220 mm.
The bases of the seats, the battery boxes, do not have to be the same dimensions as the seats themselves, although they would not want to be too much smaller so as to avoid the "pumpkin on a pimple" deformity. In fact, there is something to recommend the front of the box being located a little behind the front of the seat, to give clearance to heels. But the fore/aft length of the box has to be a minimum of 315 mm. in order to house the bottom slide. The upper slide can move back 80 mm. from the back of the lower; if the upper slide is attached to the seat centrally, the centre of gravity of the seat fully retracted or projected would still lie within the base of support provided by the lower slide, so my aim will to be to have the seat base and the box line up at the back when it is in its comfortable driving position, and to allow it to slide away when it is in any other position. The box should be the same width as the seat, but it need not be the same fore/aft length, provided the discrepancy is at the front. The final decision is a square box 420 mm. wide and long.
Because of the lifting lid I think the box rails have to be dovetailed together, rather than mitred. Now, I know that woodworkers are not supposed to admit this, but I hate doing dovetails, and any situation which can be justified for me to use a dovetail jig I will take advantage of. In this case, where the width of the pieces is not critical, and where they are small enough to handle easily, the best jig to use is the Gifkins one for use on the router table.
The Gifkins Dovetail Jig.
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Problems shows higher resolution shots as well.
Although there is just adequate room for squeezing between the two front seats in these dimensions, (it actually allows 120 mm. between them), it is not generous, and is nothing like as generous as the Freebody launch as seen below, left.
In all other respects I find the
Freebody design to be the gold standard, but in the matter of front
seating we have to depart. The front seats look too narrow to me, and I
do not think that the outward flare of the seat backs makes up for
that. Nor do I think it is necessary to have such a broad space between
the seats. The use of that gap is only occasional, and I would rather
sacrifice a little passage space for more seating comfort. Furthermore, as my seats will rotate, it will be important for them to be able to pass one another on the diagonal, so to speak. In other words, when the seat is at 45° to the midline, its most protrusive part should not bump into the other seat. That does not mean that it cannot cross the midline, as the two seats do not have to be rotated simultaneously, but it does limit their proximity to each other.
A good compromise is to reduce the seat width from 470 mm. to 420 mm. which is still comfortable, and which gives a passage of 170 mm. between them. That way, the distance between the midline and the seat is 85mm., just more than is required for the seats to rotate.
The gap between the boards in this mock-up is 220 mm.
The bases of the seats, the battery boxes, do not have to be the same dimensions as the seats themselves, although they would not want to be too much smaller so as to avoid the "pumpkin on a pimple" deformity. In fact, there is something to recommend the front of the box being located a little behind the front of the seat, to give clearance to heels. But the fore/aft length of the box has to be a minimum of 315 mm. in order to house the bottom slide. The upper slide can move back 80 mm. from the back of the lower; if the upper slide is attached to the seat centrally, the centre of gravity of the seat fully retracted or projected would still lie within the base of support provided by the lower slide, so my aim will to be to have the seat base and the box line up at the back when it is in its comfortable driving position, and to allow it to slide away when it is in any other position. The box should be the same width as the seat, but it need not be the same fore/aft length, provided the discrepancy is at the front. The final decision is a square box 420 mm. wide and long.
Because of the lifting lid I think the box rails have to be dovetailed together, rather than mitred. Now, I know that woodworkers are not supposed to admit this, but I hate doing dovetails, and any situation which can be justified for me to use a dovetail jig I will take advantage of. In this case, where the width of the pieces is not critical, and where they are small enough to handle easily, the best jig to use is the Gifkins one for use on the router table.
The Gifkins Dovetail Jig.
Like most dovetail
jigs, this one allows you only easily to use fixed spacing, so the
tails and
pins will be of nearly equal size, such as you see on the jig itself.
The exact spacing can be chosen by replacing the bottom templates and
the cutter size, but it is still fairly restricted. Nevertheless, for a
purely functional dovetail joint such as I am contemplating, and
bearing in mind that there will be at least 16 of them, the benefits
are irresistible.
Briefly, the workpiece is clamped to the jig, sitting tightly against the adjustable rest on the left, and shims are inserted between the sacrificial MDF board and the jig until the fit is perfect. The pins are cut by running a straight cutter around the contours of the template seen above. Then the mating workpiece is fixed to the other side of the jig, where the template has parallel sided grooves, and a dovetail cutter is used to make the tails. The width of the workpieces is not critical, as long as the spacing of the template grooves allows for half pins top and bottom.
A special situation arises with the jointing of the rails for the box top. Because there is an opening lid, the rails will have to be sawn through horizontally after they are glued, so the pin at that point will have to be thicker than the other pins by the thickness of the saw kerf, or about 4 mm. in my case. To achieve this the workpiece has to be moved 4 mm. on the jig, and that means either moving the rest along its calibrated scale , or using a spacer between the rest and the stock. There is no tolerance for error with dovetails, even by a small fraction of a millimetre, so all the parts have to be cut on one side with the rest secured in its first position, and then all parts are cut on their other sides after the rest is moved to its second position, or the spacer is removed. When choosing the width of the rails, you have to take into account the extra 4 mm.
The construction of the mechanism begins with the slide and swivel on the platform. A piece of 9 mm. ply is cut 400 mm. x 400 mm., and 10 mm. wide edge banding strips are cut to fit it. The top of the slide is bolted to the underneath of the platform, and the bottom of the swivel to its top.
The slide (left) and swivel (right) on the platform.
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Briefly, the workpiece is clamped to the jig, sitting tightly against the adjustable rest on the left, and shims are inserted between the sacrificial MDF board and the jig until the fit is perfect. The pins are cut by running a straight cutter around the contours of the template seen above. Then the mating workpiece is fixed to the other side of the jig, where the template has parallel sided grooves, and a dovetail cutter is used to make the tails. The width of the workpieces is not critical, as long as the spacing of the template grooves allows for half pins top and bottom.
A special situation arises with the jointing of the rails for the box top. Because there is an opening lid, the rails will have to be sawn through horizontally after they are glued, so the pin at that point will have to be thicker than the other pins by the thickness of the saw kerf, or about 4 mm. in my case. To achieve this the workpiece has to be moved 4 mm. on the jig, and that means either moving the rest along its calibrated scale , or using a spacer between the rest and the stock. There is no tolerance for error with dovetails, even by a small fraction of a millimetre, so all the parts have to be cut on one side with the rest secured in its first position, and then all parts are cut on their other sides after the rest is moved to its second position, or the spacer is removed. When choosing the width of the rails, you have to take into account the extra 4 mm.
The construction of the mechanism begins with the slide and swivel on the platform. A piece of 9 mm. ply is cut 400 mm. x 400 mm., and 10 mm. wide edge banding strips are cut to fit it. The top of the slide is bolted to the underneath of the platform, and the bottom of the swivel to its top.
The slide (left) and swivel (right) on the platform.
The
handle of the slide rubs against the platform at its front end, so a
semicircular disc needs to be cut from it. When the seat is upright the
slide handle will be on the right hand side, and it will disengage the
gears of the slide when it is pulled to the left. The handle of the
swivel projects on the left hand side and is activated by pulling it
further to the left. Although there is adequate clearance for it in the
seat's forward position it will probably get too close to the corner of
the platform as the seat rotates. This will be overcome by replacing
the cheap black plastic handle with a longer wooden one which I shall
manufacture. The same applies to the handle of the slide.
The edge banding is now glued on and the project is left for that glue to dry overnight.
The edge banding is now glued on and the project is left for that glue to dry overnight.
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125a.
The
Chinese Problem - Simply Galling?
The
ubiquitous nature of Chinese manufacture means that there is no longer
any readily available choice for sourcing components. The seat slide
which I am using is a good example. It is the only stainless steel
slide with the reach which I want, but it is made in China. So, the
quality of the product is immediately suspect. (I was not suspicious
enough). There are two slides,
and each of them has two hold down bolts installed, which lock onto the
matching nuts.
The underneath of one of the slides.
The underneath of one of the slides.
In
fitting these devices, three of the nuts went over the bolts without
trouble, but the fourth would not thread on properly. There is a not
uncommon problem particularly affecting stainless steel, called
galling, where the protective oxides on the surface of the metal are
flaked off, and the threads lock up against one another. Usually that
can be overcome with gentle tightening and the application of
lubricant. But, in this case it was useless. An examination of the
threads under magnification showed a little bit of abrasion on the
first two rings of the bolt, so I took a file to it and worked them off
to a smooth surface. Still no luck with the nut. After a fruitless hour
of filing, lubricating and tightening, I eventually discovered the
cause of the fault. The fourth bolt had a different thread to the other
three!!! It turns out that the fourth bolt is, in fact, an M8, whereas
the others are 5/16". So now I have acquired an M8 nut, in stainless,
and it all fits properly.
It is a galling experience, even if not a problem of galling per se. Quality control is evidently not high on the list of the manufacturer; nor of the importer. It is a matter of continuing chagrin to me that, in embracing the cheapness of Chinese goods, we have allowed our quality producers to go out of business, to such an extent that there is now no option other than to accept this rubbish which is flooding out of the East. It seems to be an irreversible trend, but it raises the possibility of niche markets, such as that exploited by the Lie Nielsen tool company in the USA. Seeing the poor quality of the tools produced by the big manufacturers these days, that company has found a dedicated following from those who are prepared to pay more for better, and they have flourished by producing excellent products which work. Oh, that the same would happen in boat building, and that our small band would resolve to deny Sinicization, and take up a new war cry: "A pox on mediocrity."
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However, I digress. With the platform constructed I can measure the height necessary for the tray to conceal the mechanisms. The height from the bottom of the slide to the bottom of the platform is 27 mm., but the slide handle's bottom is at the same level as the slides themselves, so it would drag along the base if the slide is not elevated away from it. There are some shims provided for that purpose, but I have already used them between the slide tops and the platform, so that the handle does not bind there. A simple set of hardwood runners is added to the bottom surface of the slide to serve the same function, and the measured height from base to platform is now 35 mm.
Hardwood runners added to the slide bottoms.
The crest rail is the decorative element of this seat, as everything else is square and boxy. I briefly entertained the thought of sloping the top of the crest rails to follow the line of the windscreens, but that would look too feline in the reverse position, so I settled on a flattened waveform shape similar to the dashboard cutout and the gloveboxes. The rail joins the stiles on top of them rather than between them, which is the more usual configuration in door and windows. Here, to follow the example of the battery box and the seat pan, it has to cap the structure rather than be sandwiched by it. Only the top of the crest rail has to reach the maximum height of the seat back, mid coaming level, so the slope down from there to the rear stiles will assist in achieving greater clearance of the seat back from the coaming bead, as the rear stiles can now be shortened to terminate far enough below the bead to avoid contact. For the sake of visual weighting, the width of the crest rail should be no greater than the width of the rear pan frame member. In order dispense with the need for multiple joined parts I want to carve the rail out of a single piece of timber. As I already have some 230 mm. wide left over from the stern covering board, I can use that.
There is a choice as to how the crest rail meets the rear stiles. If the width of the rail is to be the same as the stile, the joint can either be horizontal or sloped.
With the horizontal joint (right) there is a bit of crest rail end grain showing on the side, but more contact is available to meet the
side stile and support the joint. It also allows deeper tenoning into the rail.
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It is a galling experience, even if not a problem of galling per se. Quality control is evidently not high on the list of the manufacturer; nor of the importer. It is a matter of continuing chagrin to me that, in embracing the cheapness of Chinese goods, we have allowed our quality producers to go out of business, to such an extent that there is now no option other than to accept this rubbish which is flooding out of the East. It seems to be an irreversible trend, but it raises the possibility of niche markets, such as that exploited by the Lie Nielsen tool company in the USA. Seeing the poor quality of the tools produced by the big manufacturers these days, that company has found a dedicated following from those who are prepared to pay more for better, and they have flourished by producing excellent products which work. Oh, that the same would happen in boat building, and that our small band would resolve to deny Sinicization, and take up a new war cry: "A pox on mediocrity."
Top of Page
However, I digress. With the platform constructed I can measure the height necessary for the tray to conceal the mechanisms. The height from the bottom of the slide to the bottom of the platform is 27 mm., but the slide handle's bottom is at the same level as the slides themselves, so it would drag along the base if the slide is not elevated away from it. There are some shims provided for that purpose, but I have already used them between the slide tops and the platform, so that the handle does not bind there. A simple set of hardwood runners is added to the bottom surface of the slide to serve the same function, and the measured height from base to platform is now 35 mm.
Hardwood runners added to the slide bottoms.
The
edge banding is planed back to platform level, and the structure is
sanded, and it is now fully functional, ready to be attached to the box
top. The latter should have a side depth of just under 35 mm., in order
to avoid binding with the platform, and a similar gap will be
necessary between the platform and the skirt of the seat which will
hang down from above.
An upside down view of the mechanism. Here, the handle of the swivel is seen poking out behind the platform (right).
When the seat is facing fully forward or aft it is easily enough to reach, but it becomes more obscured when
the seat rotated to 45° and the handle moves around the platform with the seat.
With the information just obtained I can plan for the top of the box. The supporting top itself will be of 9 mm. ply, and I want to house it in rebates cut in the sides of the tray. I will start with a clearance of 4 mm. between the top of the tray sides and the platform, so the drop from tray top to box top will be 31 mm. The toggle catch requires a width of 80 mm. If the entire rail width is 80 mm. the lifting part could be 40 mm, which means a 9 mm. rebate on the underside of the box top for the support top (31+9=40). That allows the screws of the toggle to enter the rail away from rebates. It also allows the top rail to be narrower than the bottom rail which will be 100 mm. That looks better from a visual weighting point of view. Now, will the router jig work on 80 mm? As luck has it, it does.
The dovetails are cut quickly once the jig is set up, and they are quite acceptable. These below are not yet glued.
An upside down view of the mechanism. Here, the handle of the swivel is seen poking out behind the platform (right).
When the seat is facing fully forward or aft it is easily enough to reach, but it becomes more obscured when
the seat rotated to 45° and the handle moves around the platform with the seat.
With the information just obtained I can plan for the top of the box. The supporting top itself will be of 9 mm. ply, and I want to house it in rebates cut in the sides of the tray. I will start with a clearance of 4 mm. between the top of the tray sides and the platform, so the drop from tray top to box top will be 31 mm. The toggle catch requires a width of 80 mm. If the entire rail width is 80 mm. the lifting part could be 40 mm, which means a 9 mm. rebate on the underside of the box top for the support top (31+9=40). That allows the screws of the toggle to enter the rail away from rebates. It also allows the top rail to be narrower than the bottom rail which will be 100 mm. That looks better from a visual weighting point of view. Now, will the router jig work on 80 mm? As luck has it, it does.
The dovetails are cut quickly once the jig is set up, and they are quite acceptable. These below are not yet glued.
The
box top is put together and the platform with the slide and
swivel is suspended over it. The chocks which suspend it are a bit
bigger than the 4 mm.
I am aiming for, because there is not yet an aperture cut for the slide
handle. It requires a recess of about 12 mm. to be cut into the front
of the box top, corresponding with the semicircular recess in the
platform.
Seat mechanisms attached to their platform suspended over the box top.
Seat mechanisms attached to their platform suspended over the box top.
This
will be the driving position of the seat, with the sides of the
platform all lined up with the sides of the box, but the seat itself
will be longer than this by 30 mm. plus the depth of the seat back.
Next, the box is disassembled and rebates are routed in each of the sides to house the support top (the bit to which the slides are bolted inside the box top), which is glued and screwed in when the sides are glued together. Impressions from the bottom bolts of the slides are pushed into the support top while the box and platform are aligned with each other, and holes are drilled in the support top to take the bolts. The box is then run over the table saw on all four sides through the central pin. Hinges are installed on the back and the toggle clasp on the front, and the bottom half is now available to be morticed to take the stiles and sides. Openings have to be made to allow the top half of the slides to move back and forth beyond the front the box, but at the back these are not necessary if you sacrifice the last stop position on the slides. These openings could be done before the box is glued up, depending on how it is intended that they be fashioned. I will not make openings behind, so I will need some sort of buffer piece on the inside of the box top to protect the mahogany from being dented by the backward thrust of the slides. Any bit of left over metal, or even hardwood, will do the job.
The openings for the handle and the slides are cut into the front of the box top.
After being split apart from the bottom half, this upper half
has the support top glued to its base.
The seat in fully forward, neutral, and fully back positions.
The slides are only visible from below with the seat fully forward.
A similar sequence occurs with the box bottom. There is a lot of racking force going to be applied to these boxes, so I prefer to have the sides glued in rather than floating. That means using ply instead of solid wood, but it will have to be tarted up somehow to give it a touch of class. The obvious design would be to put mahogany striping on hoop pine ply, as so reflect the cockpit lagging; but that may look a bit too striped. Stripes in the cockpit, and on the deck may be enough. Any more and it might begin to look a bit too P. G. Wodehouse. I will wait and see what the mock-up looks like before committing to it.
Finally, a piece of decoration which may have more than visual impact to recommend it is a strip of contrasting beading running around the box top at the level of the hinges. Provided quality hinges are being used, the beading has to be the same thickness as the barrel of the hinge, and it is attached to either the upper or lower half of the box top only. It has two practical advantages: if attached to the top half, it could be screwed on right though the support top and into the box top sides from below, thus reinforcing the fixation of the support top; and, it can do away with the need to cut hinge mortices. The proviso of "quality" is because the thickness of the two leaves together equals the thickness of the barrel in good, cast metal hinges; however, in the sheet metal ones which are available in this small size the leaves are always less than the barrel, so the bead thickness has to be deduced from trial and error fitting.
Along the back of the box where the beading is interrupted by hinges it is in three pieces. The hinge is screwed to the box without a mortice, and the beading fills the gap between upper and lower box halves which results from there being no mortice. It does mean, however, that the hinge leaf sits proud on the lower half of the box, where there is no beading attached, and sits recessed on the upper half, where there is. Unless of course you split the beading into two halves, each the thickness of one of the hinge leaves, and that is too fussy even for me! I have to decide on this before the toggle clasp is screwed in, and the mock up below persuades me to go with it.
The front of the box top with and without beading.
Next, the box is disassembled and rebates are routed in each of the sides to house the support top (the bit to which the slides are bolted inside the box top), which is glued and screwed in when the sides are glued together. Impressions from the bottom bolts of the slides are pushed into the support top while the box and platform are aligned with each other, and holes are drilled in the support top to take the bolts. The box is then run over the table saw on all four sides through the central pin. Hinges are installed on the back and the toggle clasp on the front, and the bottom half is now available to be morticed to take the stiles and sides. Openings have to be made to allow the top half of the slides to move back and forth beyond the front the box, but at the back these are not necessary if you sacrifice the last stop position on the slides. These openings could be done before the box is glued up, depending on how it is intended that they be fashioned. I will not make openings behind, so I will need some sort of buffer piece on the inside of the box top to protect the mahogany from being dented by the backward thrust of the slides. Any bit of left over metal, or even hardwood, will do the job.
The openings for the handle and the slides are cut into the front of the box top.
After being split apart from the bottom half, this upper half
has the support top glued to its base.
The seat in fully forward, neutral, and fully back positions.
The slides are only visible from below with the seat fully forward.
A similar sequence occurs with the box bottom. There is a lot of racking force going to be applied to these boxes, so I prefer to have the sides glued in rather than floating. That means using ply instead of solid wood, but it will have to be tarted up somehow to give it a touch of class. The obvious design would be to put mahogany striping on hoop pine ply, as so reflect the cockpit lagging; but that may look a bit too striped. Stripes in the cockpit, and on the deck may be enough. Any more and it might begin to look a bit too P. G. Wodehouse. I will wait and see what the mock-up looks like before committing to it.
Finally, a piece of decoration which may have more than visual impact to recommend it is a strip of contrasting beading running around the box top at the level of the hinges. Provided quality hinges are being used, the beading has to be the same thickness as the barrel of the hinge, and it is attached to either the upper or lower half of the box top only. It has two practical advantages: if attached to the top half, it could be screwed on right though the support top and into the box top sides from below, thus reinforcing the fixation of the support top; and, it can do away with the need to cut hinge mortices. The proviso of "quality" is because the thickness of the two leaves together equals the thickness of the barrel in good, cast metal hinges; however, in the sheet metal ones which are available in this small size the leaves are always less than the barrel, so the bead thickness has to be deduced from trial and error fitting.
Along the back of the box where the beading is interrupted by hinges it is in three pieces. The hinge is screwed to the box without a mortice, and the beading fills the gap between upper and lower box halves which results from there being no mortice. It does mean, however, that the hinge leaf sits proud on the lower half of the box, where there is no beading attached, and sits recessed on the upper half, where there is. Unless of course you split the beading into two halves, each the thickness of one of the hinge leaves, and that is too fussy even for me! I have to decide on this before the toggle clasp is screwed in, and the mock up below persuades me to go with it.
The front of the box top with and without beading.
If
beading is to be used it is better to have a decent sized barrel on the
hinge, and it is preferable to get a hinge whose leaf width is the same
as the thickness of the box side to which it will be attached. I was
able to find some stainless steel hinges with 20 mm. leaves and a 7 mm.
barrel, which suits the purpose well. It means that the box top will be
a little under 7 mm. higher than planned, which is inconsequential.
The size is right, but oops, the quality is Chinese. This hinge's pin has slipped out and needs peening.
The size is right, but oops, the quality is Chinese. This hinge's pin has slipped out and needs peening.
Red
mahogany, the eucalypt, is used for the trim again. Rather than using a
cockbead here, where there is likely to be some traffic, I am using
flush beading. Only the hinge barrel will protrude from the box top.
The beading is laid over the under-surface of the support top (left), and the box top is re-erected with the beading (right).
The beading is laid over the under-surface of the support top (left), and the box top is re-erected with the beading (right).
To
determine the dimensions of the rest of the box, I had to estimate the
height of the seat itself. The rear seat is a mere 350 mm. off the
sole, and quite laid back, but the more business-like driver's seat has
to be more upright and higher. A minimum of 450 mm. is needed and
500 mm.
is better. The cushion will account for 35 mm. with a person sitting on
it, and the top of the swivel is 30 mm. above the platform. The seat
itself will be ply, but it will have to be mounted on wedges to give it
a rake backwards. I think 100 mm. will easily be consumed between the
top of the platform and the top of the compressed cushion. That leaves
400 mm. to
find below the swivel. We already have: 9 mm. in the platform, 4 mm.
in the gap, 80 mm. in the top rail, ~7 mm. in the bead, or a total of
100 mm. The bottom rail is also 100 mm. That means that the stiles have
to be 200 mm. long. The proportion looks good if they are 60 mm. wide,
which means that one will actually be 60, while its neighbour, to which
it will be edge joined (or edge-to-face joined to be more precise),
will be 40. The tenons of the 60 mm. stiles can
be set back by 20 mm. to avoid having to cut mortices into the tails
and pins of the rails, but, even so, I think it would be wise to use
epoxy to glue these components because of the potential weakening of
the dovetail joints. The 9 mm. plywood box sides will fit into 6 mm.
grooves
cut in the inner edges of rails and stiles. Their visible surfaces will
measure 300 mm. x 200 mm. Naturally, they will have to be rebated along
their edges. (I could have used 6 mm. ply here, but I happened to have
some 9 mm. left over from the cockpit lagging).
So, the next step is to cut the mortices and grooves in the bottom half of the box top, before it is permanently fixed to its top half. That can be done on the router table. Then, the rail of the box bottom has to be constructed, back on the dovetail jig, and morticed and grooved on its upper surface. A true box bottom will have to be fitted to accept the batteries, but it can be a drop-in structure resting on ledger strips. That will allow later access to screw brackets between the box and the sole and floors, once the final position of the seat complex is decided.
A skin fitting, corresponding to that on the lagging, has to be fitted to the outer box side to allow the battery cabling to enter the box. Any decorative flourishes on the box sides will have to take into account the passage of the fitting.
The box upper rail with loosely fitted stiles, awaiting its lower rail. The exposed lower tenons of the front stiles can be seen set back
20 mm.to avoid entering the dovetail joints. These stiles are all identical in size, so are interchangeable. The quarter cut ones, such
as the one on the right above can go on the back of the seat box, where their better look can be appreciated by rear seat
passengers. The back cut ones, such as the example on the left above, can remain on the front where they will not be seen.
I use shallow (no.0) biscuits to help align the adjoining stiles when they are glued in, so the grooves in the stiles, which house the ply sides, have to be shallower than would result in an exposed biscuit. 5 mm. is adequate. They have to be 6 mm. thick, so the tenons may as well be 6 mm. too. That way I can use the same router bit, and just deepen it for the tenon mortices.
Box top hinged at the back, and the biscuits for joinery of the stiles.
Finally, the stripes on the hoop pine ply have to be housed. I do not want to have independent, adjoining strips such as I have on the lagging, because I want the strength of the ply as an integral part of the design of the box. So, the contrasting stripes of mahogany, if I decide to use them, will be just beads housed in shallow trenches which penetrate no more that one ply of thickness into the side. The cockpit lagging strips are 100 mm. wide, so, with a 300 mm. wide box side, two simple beads on them would blend in well with the general design. If the seat can be positioned so that the 60 mm. diameter skin fittings can enter the sides without traversing one of the beads, so much the better.
The rail of the box bottom is a simple dovetailed box itself, whose upper surface accepts the tenons from the stiles. While it is gluing up, I check the positions of the stiles, and then finish the hinge fixation of the seat mechanisms to the box top.
The seat box from the rear, waiting for the mortices to be cut for the stiles (left),
and from the front with the lifting section hinged on and opened (right).
The weight of the top is already a good deal heavier than the bottom at this stage, but the batteries will tend to even it up. Even so, if the design of the seat itself does not stop it from opening beyond 90°, which it almost certainly won't, there will need to be a limiting device fitted to the opening section to stop it crashing into the back of the box. Even something as simple as a leather strap would work, provided it does not interfere with the battery cabling.
With some hoop pine panels dropped into place the structure does look very Spartan. A pair of contrasting strips certainly makes it look smarter, and I think I will go with them. One more trial with the box inside the boat will let me decide.
With the unembellished panels...
...and the embellished.
Even at this degree of opening, the seat back will be invading the rear
seat space.
So, the next step is to cut the mortices and grooves in the bottom half of the box top, before it is permanently fixed to its top half. That can be done on the router table. Then, the rail of the box bottom has to be constructed, back on the dovetail jig, and morticed and grooved on its upper surface. A true box bottom will have to be fitted to accept the batteries, but it can be a drop-in structure resting on ledger strips. That will allow later access to screw brackets between the box and the sole and floors, once the final position of the seat complex is decided.
A skin fitting, corresponding to that on the lagging, has to be fitted to the outer box side to allow the battery cabling to enter the box. Any decorative flourishes on the box sides will have to take into account the passage of the fitting.
The box upper rail with loosely fitted stiles, awaiting its lower rail. The exposed lower tenons of the front stiles can be seen set back
20 mm.to avoid entering the dovetail joints. These stiles are all identical in size, so are interchangeable. The quarter cut ones, such
as the one on the right above can go on the back of the seat box, where their better look can be appreciated by rear seat
passengers. The back cut ones, such as the example on the left above, can remain on the front where they will not be seen.
I use shallow (no.0) biscuits to help align the adjoining stiles when they are glued in, so the grooves in the stiles, which house the ply sides, have to be shallower than would result in an exposed biscuit. 5 mm. is adequate. They have to be 6 mm. thick, so the tenons may as well be 6 mm. too. That way I can use the same router bit, and just deepen it for the tenon mortices.
Box top hinged at the back, and the biscuits for joinery of the stiles.
With
machine cut tenons there is often a little discrepancy between the
surfaces of the rails and stiles, and these parts fall into that
category. The stiles all sit about 0.25 mm. proud of the rails. Before
the grooves are cut for the ply sides, the stiles are planed back to a
level flush with the rails, and, using the same set up on the router as
was used to cut the grooves in the rails, and using the planed surfaces
of the stiles as registers for the router fence, exactly corresponding
grooves result, which are able to house the ply perfectly.
Finally, the stripes on the hoop pine ply have to be housed. I do not want to have independent, adjoining strips such as I have on the lagging, because I want the strength of the ply as an integral part of the design of the box. So, the contrasting stripes of mahogany, if I decide to use them, will be just beads housed in shallow trenches which penetrate no more that one ply of thickness into the side. The cockpit lagging strips are 100 mm. wide, so, with a 300 mm. wide box side, two simple beads on them would blend in well with the general design. If the seat can be positioned so that the 60 mm. diameter skin fittings can enter the sides without traversing one of the beads, so much the better.
The rail of the box bottom is a simple dovetailed box itself, whose upper surface accepts the tenons from the stiles. While it is gluing up, I check the positions of the stiles, and then finish the hinge fixation of the seat mechanisms to the box top.
The seat box from the rear, waiting for the mortices to be cut for the stiles (left),
and from the front with the lifting section hinged on and opened (right).
The weight of the top is already a good deal heavier than the bottom at this stage, but the batteries will tend to even it up. Even so, if the design of the seat itself does not stop it from opening beyond 90°, which it almost certainly won't, there will need to be a limiting device fitted to the opening section to stop it crashing into the back of the box. Even something as simple as a leather strap would work, provided it does not interfere with the battery cabling.
With some hoop pine panels dropped into place the structure does look very Spartan. A pair of contrasting strips certainly makes it look smarter, and I think I will go with them. One more trial with the box inside the boat will let me decide.
With the unembellished panels...
...and the embellished.
Unvarnished,
and not yet glued together, the seat base looks very pedestrian, if
that is possible for a seat. It also takes up quite a lot of room. I
may have to rethink the placement of the fridge later, as that was
meant to go behind the passenger's front seat.
Furthermore,
it can now be appreciated that the opening of the seat box, once
the seat is attached to it, will bring the seat back down on the rear
seat passenger's knees; all the more reason for a restraint.
Even at this degree of opening, the seat back will be invading the rear
seat space.
The desk chair, set to a
comfortable height, shows that there will be adequate space for the
seat to go on top of this box. And the skin fitting on the lagging
corresponds nearly enough to the front of the box side panel.
Furthermore, the box lies just behind the little hatch in the sole
which will
allow extra cabling to come up into it if necessary, so the position is
good.
The skin fitting on the lagging for the battery cables to enter the seat box.
The skin fitting on the lagging for the battery cables to enter the seat box.
The
great pity about boxes is that they look boxy. As it stands at the
moment this seat base detracts from the appearance of the cockpit, and
will need a good deal of work before it begins to blend in. The
striping of the panels will help, and the varnishing of the wood will
go a long way, but it needs more than that. The sharp edges have to be
rounded, and a sympathetic seat has to be devised. But it also occurs
to me that the back of the seat box is now within reach of the feet of
the rear seat passengers. I have had to dispense with the angled foot
rests for the driver because of the opening dash console door, but
there is no reason why individual rests could not be installed on the
back of the front seats. They would serve the dual purpose of softening
the boxy look, and adding a touch of comfort. They would not help with
the refrigerator, or the companionway ladder, but they deserve serious
consideration.
Giving further thought to the refrigerator, it also occurs to me that the current plan for battery placement is not set in concrete. I have allowed for two drive batteries to be stowed under the front passenger's seat, and the house battery to go under the driver's. But if one of these compartments were empty of batteries, it could serve as a refrigerator. The house battery is not an absolute necessity anyway, because the DC converter will easily manage the maximum load. If the empty seat were then turned into a fridge it would need the driver to get off the seat to get into the it, and that is a considerable inconvenience. But if the drive batteries were under the driver's seat and the fridge under the front passenger's, the inconvenience would be less (at least to the driver!).
These ideas will have to ferment for a while.
Meanwhile, back at the box, the action of the very stiff seat swivel on the box lid is taking its toll. The torque it applies tends to twist against the hinges and displace the structure sideways to the left. Only the clasp in front tends to resist rotational torque, and that not very well. I have to resort to an old box-maker's trick of lining the box with a layer whose lip rises above the level of the hinges and guides the lid to close flush with the sides. These lips only work when there is a space in the lid into which they can fit, and because of the support top in my box lid, which is flush with the bottom of the lid, there is no room for a lip. However, the use of the contrasting bead at hinge level has created a 7 mm. space where the lip can fit, and that should be sufficient to resist the torque of the swivel. So, the box top below hinge level needs some lining.
To illustrate the point, here is an old jewellery box in American oak and wenge. The sides are perfectly aligned because of the lip rising above the bottom half of the box into the lid.
The closed and perfectly aligned box and lid.
The rising lip which registers the lid on the box.
Giving further thought to the refrigerator, it also occurs to me that the current plan for battery placement is not set in concrete. I have allowed for two drive batteries to be stowed under the front passenger's seat, and the house battery to go under the driver's. But if one of these compartments were empty of batteries, it could serve as a refrigerator. The house battery is not an absolute necessity anyway, because the DC converter will easily manage the maximum load. If the empty seat were then turned into a fridge it would need the driver to get off the seat to get into the it, and that is a considerable inconvenience. But if the drive batteries were under the driver's seat and the fridge under the front passenger's, the inconvenience would be less (at least to the driver!).
These ideas will have to ferment for a while.
Meanwhile, back at the box, the action of the very stiff seat swivel on the box lid is taking its toll. The torque it applies tends to twist against the hinges and displace the structure sideways to the left. Only the clasp in front tends to resist rotational torque, and that not very well. I have to resort to an old box-maker's trick of lining the box with a layer whose lip rises above the level of the hinges and guides the lid to close flush with the sides. These lips only work when there is a space in the lid into which they can fit, and because of the support top in my box lid, which is flush with the bottom of the lid, there is no room for a lip. However, the use of the contrasting bead at hinge level has created a 7 mm. space where the lip can fit, and that should be sufficient to resist the torque of the swivel. So, the box top below hinge level needs some lining.
To illustrate the point, here is an old jewellery box in American oak and wenge. The sides are perfectly aligned because of the lip rising above the bottom half of the box into the lid.
The closed and perfectly aligned box and lid.
The rising lip which registers the lid on the box.
Doing
the same on the seat box top is relatively straight forward. I
have the advantage of being able to gain access to the box inside from
underneath, so the lining boards can be tapped right up to the level of
the support top.
The
lining lip on the box top.
The
stripes are now applied to the panels, and the box is returned to the
boat to see how it looks. I like the appearance, and do not find the
stripes too obtrusive.
The strips on the seat base appear to be wider than their counterparts on the dash bulkhead,
but they are actually the same. It is an illusion of perspective.
The strips on the seat base appear to be wider than their counterparts on the dash bulkhead,
but they are actually the same. It is an illusion of perspective.
Once
again, the box is disassembled for the stile components to be glued
together. While they are drying they are returned to the box to ensure
correct alignment.
Careful
selection of timber can ensure that the grain pattern on adjoining
stiles is continuous, making the stile appear to come from a single
piece of wood, rather than from two separate ones, if that is important.
After the glue up and a coat of varnish the box is beginning to look right in the cockpit. Now for the same on the other side, hopefully a bit more quickly than the first.
The trimmed and varnished box, although the hoop pine is still raw at this stage. It will yellow a bit with its finish.
After the glue up and a coat of varnish the box is beginning to look right in the cockpit. Now for the same on the other side, hopefully a bit more quickly than the first.
The trimmed and varnished box, although the hoop pine is still raw at this stage. It will yellow a bit with its finish.
126. The
Forward Accommodation
This
business with the driver's seating has gone on so long that it is time
for a chapter change. What I have actually described under the previous
heading is the construction of a battery box, so for the actual seat
which will support the poor driver's bum, and that of his forward
passenger, I wanted a new heading. My seats, if you disregard their
mechanisms, will be simpler than the
Freebody seats, because their ability to rotate does away with the need
to have the Rolls Royce trays folding down from behind them. So, they
do not have to be as thick. They do have to be substantial enough to
frame supports for bottom and rear cushions, and they have to be no
more than 420 mm. wide.
The simplest concept is a pair of seat rails enclosing a ply seat base, and a pair of seat back stiles, connected by a crest rail, enclosing a ply seat back. The width of the solid components has to be enough to contain the cushions and limit their sideways or forward displacement. There also has to be a base which can bolt onto the swivel which presently sits atop the battery box. The base has to incline the seat bottom back by 5°, and the seat back has to be tall enough to support the occupant in more comfort than is provided by the average desk chair which stops at lumbar level. Those few boats which do have solid seats (as opposed to the Lloyd loom chairs) seem to have their crest rails rising to about half way up the coaming. The seat back is inclined at about 100° to the seat bottom, which is slightly less than the angle on my rear seat.
The critical measurement with my seats will be their maximum rotational dimension. In other words, will they bump into the lagging? Luckily, the cockpit widens as it passes sternwards, and the flare of the lagging means that it is less constricted as it rises. So there is more room for the seat to turn, the higher it gets, and the further back it is pushed. A scale drawing of the seat in its neutral position shows that there is room to rotate, and pushing the seat back should only increase the space available. Nevertheless, it will be a tight fit to get it right, and this is no place for untested theory.
A pan view of the forward accommodation, seat 30 mm. longer than the base box.The
clearance shown is from the lagging at box top level. The distance between the boxes
is 200 mm., which is just enough for legs to get through.
I have to make a full size model and test it for fit. The seat bottom will be represented by a 420 mm. x 420 mm. piece of ply. The seat back, which is the troublesome component, will be represented by a frame work of scrap pieces held at an adjustable angle to the bottom. There is some freedom allowed by the fact that the battery box is not in a fixed position yet, so a compromise position should be possible. Then it all has to be designed to look good. The seat bottom is first propped up on two 5° wedges on top of the swivel, and its clearance on a full arc is confirmed.
The seat bottom clearing the lagging.
The simplest concept is a pair of seat rails enclosing a ply seat base, and a pair of seat back stiles, connected by a crest rail, enclosing a ply seat back. The width of the solid components has to be enough to contain the cushions and limit their sideways or forward displacement. There also has to be a base which can bolt onto the swivel which presently sits atop the battery box. The base has to incline the seat bottom back by 5°, and the seat back has to be tall enough to support the occupant in more comfort than is provided by the average desk chair which stops at lumbar level. Those few boats which do have solid seats (as opposed to the Lloyd loom chairs) seem to have their crest rails rising to about half way up the coaming. The seat back is inclined at about 100° to the seat bottom, which is slightly less than the angle on my rear seat.
The critical measurement with my seats will be their maximum rotational dimension. In other words, will they bump into the lagging? Luckily, the cockpit widens as it passes sternwards, and the flare of the lagging means that it is less constricted as it rises. So there is more room for the seat to turn, the higher it gets, and the further back it is pushed. A scale drawing of the seat in its neutral position shows that there is room to rotate, and pushing the seat back should only increase the space available. Nevertheless, it will be a tight fit to get it right, and this is no place for untested theory.
A pan view of the forward accommodation, seat 30 mm. longer than the base box.The
clearance shown is from the lagging at box top level. The distance between the boxes
is 200 mm., which is just enough for legs to get through.
I have to make a full size model and test it for fit. The seat bottom will be represented by a 420 mm. x 420 mm. piece of ply. The seat back, which is the troublesome component, will be represented by a frame work of scrap pieces held at an adjustable angle to the bottom. There is some freedom allowed by the fact that the battery box is not in a fixed position yet, so a compromise position should be possible. Then it all has to be designed to look good. The seat bottom is first propped up on two 5° wedges on top of the swivel, and its clearance on a full arc is confirmed.
The seat bottom clearing the lagging.
Then
the back is added, inclined at 10° to the bottom, and the arc is
checked again. There is just adequate clearance, taking into account
the possibility that the back may bend a little further back with
weight on it.
Thus,
provided that the seat back is no further back than the back of the
seat bottom (phew), a simple design as shown above, will be able to
turn unhindered. In order to rotate fully to 180° the seat must be
pushed right back on its slides so that the steering wheel is avoided.
Before cutting the timber for the seat I finish off the battery box with ledger strips and a lifting bottom panel of 9 mm. ply to support the battery. The battery cables enter the box through the skin fitting whose nylon extension is seen on the bottom right of the photos below.
The interior of the driver's seat box.
The starboard side of the driver's seat box with the skin fitting for the battery cable.
Before cutting the timber for the seat I finish off the battery box with ledger strips and a lifting bottom panel of 9 mm. ply to support the battery. The battery cables enter the box through the skin fitting whose nylon extension is seen on the bottom right of the photos below.
The interior of the driver's seat box.
The starboard side of the driver's seat box with the skin fitting for the battery cable.
Taking
my life in my hands I actually sat on that seat mock-up, and it stayed
together long enough to convince me that a 5° rake is too much for
the driver's seat. It is too laid back, and brings the thighs too close
to the steering wheel. Even a dead flat seat seems better, or a very
slightly raked one at, say, 2.5°. That may seem like splitting
hairs, but it does make a difference. I suppose I could take a lead
from the Lloyd loom chairs which are found on the old boats, and copy
their angles, but they all seem to sit very high, and my wheel is not
designed for that. So, I will keep the 100° angle between seat pan
and back, and just tilt the whole structure forwards a little. That
will give even more clearance from the lagging and the wheel.
As construction on the second box begins it is possible to place the two on the sole to gauge their leg clearance in between. As I expected, it is not luxurious, but it is adequate.
As construction on the second box begins it is possible to place the two on the sole to gauge their leg clearance in between. As I expected, it is not luxurious, but it is adequate.
To begin
the seat itself, I attach two runners to the bottom of the seat pan,
which is a piece of 6 mm. ply. The runners are sloped at 2.5°, and
extend forwards nearly
to
the edge of the ply, to support the weight of
the legs. Behind, where the runners are quite thin, there is no need
for any extension behind the level of the swivel. In this area, the
seat back will be tenoned into the sides and the ply will run into
supports, so no practical purpose would be served by the runners
extending back that far.
The outer dimension of the seat will have to be the same as that of the box in the athwartships direction. The pan frame will be made of 20 mm. mahogany, which will rise far enough above the pan to enclose the cushion. The ply will be housed in grooves cut in the mahogany, 9 mm. deep. So, the ply has to be 398 mm. wide. The pan is 30 mm. longer than the base, which lies forward of the box, so its fore/aft dimension will be 428 mm.
The runners are glued onto the underneath of the pan, and holes have to be cut in the seat itself to allow the nuts to be tightened onto the swivel. The weakness caused by those holes is compensated for by making the runners wider that is needed purely to house the bolts, and gluing and screwing them to the ply. The weight of the seat is taken by the swivel, and, in a sense, the seat is a monocoque construction, rather than a chassis and body style. The frame does not support the seat; rather, the seat supports the frame.
Here, the seat pan is screwed to the runners underneath, which are bolted to the swivel.
The outer dimension of the seat will have to be the same as that of the box in the athwartships direction. The pan frame will be made of 20 mm. mahogany, which will rise far enough above the pan to enclose the cushion. The ply will be housed in grooves cut in the mahogany, 9 mm. deep. So, the ply has to be 398 mm. wide. The pan is 30 mm. longer than the base, which lies forward of the box, so its fore/aft dimension will be 428 mm.
The runners are glued onto the underneath of the pan, and holes have to be cut in the seat itself to allow the nuts to be tightened onto the swivel. The weakness caused by those holes is compensated for by making the runners wider that is needed purely to house the bolts, and gluing and screwing them to the ply. The weight of the seat is taken by the swivel, and, in a sense, the seat is a monocoque construction, rather than a chassis and body style. The frame does not support the seat; rather, the seat supports the frame.
Here, the seat pan is screwed to the runners underneath, which are bolted to the swivel.
The modern boat seats of plastic
are well suited to this sort of support, but wood is not. There is a
lot of force applied to the joint between the seat back and the seat
bottom, and a simple mortice and tenon might not take the strain. The
Freebody seats overcome the problem by widening the back frame stiles
to meet the box bottom along a long joint. Also, because of the fold
out tray at the back, the seat back is itself a box of sorts, and this
can add strength as well.
The Freebody seat.
This results in a long seat, which is all very well in a long boat, but I want to keep mine as short as practical for the sake of the rear seat passengers. So, I will make two changes: the first will be to move the side stiles of the seat to a relatively more forward position on the seat pan frame. This will effectively house the back cushion entirely within the framework of the back, while, at the same time, maintaining the shortness of the seat and the strength of the joint. The second change will be to dispense with the feather edge where the side stile meets the seat pan frame, or, in the Freebody example, where the back meets the base. It is neater, marginally stronger and less prone to damage if the stile is inset slightly into the pan frame. That allows the pan frame to be straight edged and does away with the scoop seen above. As my pan frame is a lot narrower than the base side above, any scooping would seriously weaken it.
The frame for the seat pan will not be subject to a lot of traction, as it is the pan itself which takes the brunt, so there is no need for dovetail joinery. The frame can be connected with spline reinforced mitres. The members all go together without much fuss. You just have to remember to cut the grooves in the front and back pieces at 2.5° to their faces. With mitre joinery it is easier to make the joints at right angles to the timber than to work out compound angles, so, even although the seat back will be at 100° to the seat bottom, the rear frame member of the seat bottom is joined to it at 90°. The extra 10° will have to be introduced on another level.
The seat pan frame rises 20 mm. above the pan to retain the cushion. Simple mitre joinery is used.
The Freebody seat.
This results in a long seat, which is all very well in a long boat, but I want to keep mine as short as practical for the sake of the rear seat passengers. So, I will make two changes: the first will be to move the side stiles of the seat to a relatively more forward position on the seat pan frame. This will effectively house the back cushion entirely within the framework of the back, while, at the same time, maintaining the shortness of the seat and the strength of the joint. The second change will be to dispense with the feather edge where the side stile meets the seat pan frame, or, in the Freebody example, where the back meets the base. It is neater, marginally stronger and less prone to damage if the stile is inset slightly into the pan frame. That allows the pan frame to be straight edged and does away with the scoop seen above. As my pan frame is a lot narrower than the base side above, any scooping would seriously weaken it.
The frame for the seat pan will not be subject to a lot of traction, as it is the pan itself which takes the brunt, so there is no need for dovetail joinery. The frame can be connected with spline reinforced mitres. The members all go together without much fuss. You just have to remember to cut the grooves in the front and back pieces at 2.5° to their faces. With mitre joinery it is easier to make the joints at right angles to the timber than to work out compound angles, so, even although the seat back will be at 100° to the seat bottom, the rear frame member of the seat bottom is joined to it at 90°. The extra 10° will have to be introduced on another level.
The seat pan frame rises 20 mm. above the pan to retain the cushion. Simple mitre joinery is used.
In its neutral driving position
the seat is flush with the back of the battery box, but overhangs it by
30 mm. in the front, to make room for heels. To get into the reverse
position for meals the seat is first pushed back, then rotated.
In its backwards position the seat lies flush with the front of the battery box until it is rotated.
In its backwards position the seat lies flush with the front of the battery box until it is rotated.
From behind, with
the seat rotated, you can see the lever for the swivel poking thought
the aperture in the front frame member. As the seat now overhangs the
battery box behind, there is again room for heels when
facing backwards.
Seat facing forward for driving (left), and reversed for meals (right).
Seat facing forward for driving (left), and reversed for meals (right).
The seat
back takes a lead from the battery box, in that it will be framed by 60
mm. stiles behind, which enclose a Hoop pine ply panel, duly striped,
which runs between the rear member of the pan frame, below, to the
crest rail above. It is firmly anchored to the pan frame by wide
sloping side stiles which are attached to the rear stiles, as in the
battery box, and to the side members of the pan frame, by mortice and
tenon joints which will be pegged at the front via the inside of the
side frames, from underneath the seat pan.
The side stiles will be shaped from 150 mm. wide timber, and that raises a theoretical issue with cross grain joinery. The shrinkage and expansion of the stile will occur across the top edge of the seat pan frame, and will possibly cause movement in that critical joint. However, I feel that to allow for movement by having non-glued joinery would be to invite disaster. I think it is best to risk it by firm glued fixation and copious varnishing of well dried timber. As the temperature in the garage has been over 40°C for the last week I think that the already kiln dried timber qualifies as well dried. The natural stability of mahogany will also work in my favour here, so the plan is to use a long stub tenon on the side stile, with a deeper extension into the pan frame at its forward end. The rear 20 mm. will be haunched so as not to interfere too much with the mitre joint of the pan frame. The side stile, which is stabilised and reinforced by the back stile, will be epoxy glued into the pan frame. Any residual movement in the seat will occur as a result of looseness in the hardware, rather than the woodwork.
Before fitting the stiles to the pan frame I have to convert the top of the frame's rear member to the angle of the seat back. At the moment the member is sitting in a vertical plane, so it has to have 12.5° shaved off its rear edge. 2.5° of than is to bring it into coplanarity with the sides of the frame, and the other 10° to set up the 100° joint between the back and the pan. That will allow the rear stiles to have square cut ends, but it will mean that care will be needed with the angulation of the tenons. If they are too deep they could come through the front face of the frame member. An alternative would be to angulate the tenons so that they enter the frame member parallel to its faces, but, as most of the force will be taken by the side stiles I think that shallow non-angulated tenons on the rear stiles will be adequate. If they are set back a little from the centre of the stile that will help too. Angulating the top of the rear frame member means also angulating the mitre joint to the side members.
The angulated rear and side member parts.
The same consideration applies to the groove in the rear frame member which will house the plywood component of the seat back. It has to be at a 12.5° angle to the face. Cutting mortices at angles other than parallel to the face of a board is not a job for hand work. The router table can do it, but the fence has to be firmly anchored to the table so that the sharp edge of the board does not ride under it and allow the mortice to wander. It also results in a flat edge on the frame which is thicker than the end of the stiles which are to join it, so the difference has to be hidden on the inside of the seat. That, in turn, would make the side stile end a bit more complex, were it not for the inset which I intend to give it into the side frame. Doing that will allow me to shave off the top of the side frame so that it presents a flat surface for the stile, all the way back to the rear stile.
The rear stiles are fitted into the mortices and the ply back is slotted in to fit, leaving the top proud to give me maximum flexibility with the shape of the crest rail.
The rear stiles are fitted to the rear pan frame member.
The plywood back is slotted into position.
The side stiles will be shaped from 150 mm. wide timber, and that raises a theoretical issue with cross grain joinery. The shrinkage and expansion of the stile will occur across the top edge of the seat pan frame, and will possibly cause movement in that critical joint. However, I feel that to allow for movement by having non-glued joinery would be to invite disaster. I think it is best to risk it by firm glued fixation and copious varnishing of well dried timber. As the temperature in the garage has been over 40°C for the last week I think that the already kiln dried timber qualifies as well dried. The natural stability of mahogany will also work in my favour here, so the plan is to use a long stub tenon on the side stile, with a deeper extension into the pan frame at its forward end. The rear 20 mm. will be haunched so as not to interfere too much with the mitre joint of the pan frame. The side stile, which is stabilised and reinforced by the back stile, will be epoxy glued into the pan frame. Any residual movement in the seat will occur as a result of looseness in the hardware, rather than the woodwork.
Before fitting the stiles to the pan frame I have to convert the top of the frame's rear member to the angle of the seat back. At the moment the member is sitting in a vertical plane, so it has to have 12.5° shaved off its rear edge. 2.5° of than is to bring it into coplanarity with the sides of the frame, and the other 10° to set up the 100° joint between the back and the pan. That will allow the rear stiles to have square cut ends, but it will mean that care will be needed with the angulation of the tenons. If they are too deep they could come through the front face of the frame member. An alternative would be to angulate the tenons so that they enter the frame member parallel to its faces, but, as most of the force will be taken by the side stiles I think that shallow non-angulated tenons on the rear stiles will be adequate. If they are set back a little from the centre of the stile that will help too. Angulating the top of the rear frame member means also angulating the mitre joint to the side members.
The angulated rear and side member parts.
The same consideration applies to the groove in the rear frame member which will house the plywood component of the seat back. It has to be at a 12.5° angle to the face. Cutting mortices at angles other than parallel to the face of a board is not a job for hand work. The router table can do it, but the fence has to be firmly anchored to the table so that the sharp edge of the board does not ride under it and allow the mortice to wander. It also results in a flat edge on the frame which is thicker than the end of the stiles which are to join it, so the difference has to be hidden on the inside of the seat. That, in turn, would make the side stile end a bit more complex, were it not for the inset which I intend to give it into the side frame. Doing that will allow me to shave off the top of the side frame so that it presents a flat surface for the stile, all the way back to the rear stile.
The rear stiles are fitted into the mortices and the ply back is slotted in to fit, leaving the top proud to give me maximum flexibility with the shape of the crest rail.
The rear stiles are fitted to the rear pan frame member.
The plywood back is slotted into position.
A
trial rotation at this juncture gives me cause for concern: the seat
back hits the beading on the coaming; but the joints are not secure
yet, and the weight of the back is opening them backwards a bit. I will
have to wait for the glue up before planning any relieving cuts.
The crest rail is the decorative element of this seat, as everything else is square and boxy. I briefly entertained the thought of sloping the top of the crest rails to follow the line of the windscreens, but that would look too feline in the reverse position, so I settled on a flattened waveform shape similar to the dashboard cutout and the gloveboxes. The rail joins the stiles on top of them rather than between them, which is the more usual configuration in door and windows. Here, to follow the example of the battery box and the seat pan, it has to cap the structure rather than be sandwiched by it. Only the top of the crest rail has to reach the maximum height of the seat back, mid coaming level, so the slope down from there to the rear stiles will assist in achieving greater clearance of the seat back from the coaming bead, as the rear stiles can now be shortened to terminate far enough below the bead to avoid contact. For the sake of visual weighting, the width of the crest rail should be no greater than the width of the rear pan frame member. In order dispense with the need for multiple joined parts I want to carve the rail out of a single piece of timber. As I already have some 230 mm. wide left over from the stern covering board, I can use that.
There is a choice as to how the crest rail meets the rear stiles. If the width of the rail is to be the same as the stile, the joint can either be horizontal or sloped.
With the horizontal joint (right) there is a bit of crest rail end grain showing on the side, but more contact is available to meet the
side stile and support the joint. It also allows deeper tenoning into the rail.
If the rail width is
allowed to be less than the stile another configuration is possible.
This seems to have all the disadvantages of the others with none
of the advantages, and looks bad too.
This seems to have all the disadvantages of the others with none
of the advantages, and looks bad too.
So, the
design of choice is the second one with the horizontal joint.
Reproducing the angles of the dash and gloveboxes requires a timber
width of 175 mm. Once the crest rail is cut it is clamped to the rear
stiles to gauge the cut-off point for them, and then it is grooved for
the ply back and fitted into place.
Before and after trimming the rear stiles to length.
Before and after trimming the rear stiles to length.
Again testing for
clearance on rotation, it seems that all is now well. But before I go
much further I shall have to glue the pan frame together, as there is
still too much free movement to be certain.
Testing for rotational clearance...
...just adequate.
Testing for rotational clearance...
...just adequate.
The next step is to fashion the
side stiles for the seat back. They will start out 40 mm. wide at the
top, but will broaden to 150 mm. where they meet the lateral pan frame
members. Their ends have to be cut at 10° so that they sit tight
against both rear stiles and frame members. Their tenons, which have
already been described, have to be angulated 10° so that they can
enter the frames perpendicular to their edges. The forward most part of
the tenon must be as deep as possible so that it can be pegged
underneath the seat pan.
A template for
shaping them is cut out of scrap ply and clamped into place, giving a
hint of what they will look like when finished.
The side stile template.
The side stile template.
The only question now is: "is
the back too tall for the base?" When the stripes are added to the ply
it will appear to be even taller than it is now.
The view of the driver's seat from dead astern.
I think it is too tall. So, another 20 mm. off the stiles should fix the problem. It will also bring the top of the crest rail down to the mid-coaming height which it should occupy. In the meantime, it is time to glue up the pan frame and key its mitre joints.
The seat pan is removed from the swivel to glue up its frame.
While that is setting up, I can get on with the other seat, whose box has already begun. I have abandoned the idea of housing the refrigerator in the box of one of the seats. They will both house batteries only, or perhaps some sort of tool kit as well, so the design does not have to be altered for the second seat. At the rate I have been going with the first one, it will take me most of the rest of this month to finish the second one, so I have moved the other tasks, which were set down for February, into March. But, as an inducement to allow the other half of this boat-building team to make her contribution, I have had foam cushion inserts made to fit the forward seats. Hopefully, they will be upholstered in short time!! Incidentally, the types of foam vary according to their intended use. The seat pan uses 65 mm. of high density foam, whereas the back can get by with 55 mm. of medium density. On the rear seat, where the passengers can luxuriate a bit more, I will be using 100 mm. on the pan and 75 mm. on the back.
The foam cushion inserts for the seating.
The view of the driver's seat from dead astern.
I think it is too tall. So, another 20 mm. off the stiles should fix the problem. It will also bring the top of the crest rail down to the mid-coaming height which it should occupy. In the meantime, it is time to glue up the pan frame and key its mitre joints.
The seat pan is removed from the swivel to glue up its frame.
While I am waiting
for that to dry I fit the hatch holder to the seat. I don't know why I
try to convince myself that the leather strap idea would ever satisfy
me. Whenever I see an expensive alternative I can't resist.
The hatch limiter will stop the seat back from impinging on the passengers' knees if I have to attend to the battery.
The hatch limiter will stop the seat back from impinging on the passengers' knees if I have to attend to the battery.
To slot
the pan frame for keys a carriage is constructed which can hold the
structure with its sides at 45° to the table of the saw, while the
fence determines the distance of the cut from the bottom of the frame.
As the frame is made up of wider members at the front than at the back,
there will be three keys in the front corners and two in the rear.
Contrasting keys of red mahogany are inserted and planed back after the
glue has dried.
The key cutting jig (left), and the key slots (right).
After planing.
In the meantime, I have reconsidered the idea of insetting the side stile into the lateral frame member. I think that a rebate to house it back near the rear corner would weaken the mitre joint, especially as the ply is housed in a groove there as well. So, I will mount the side stile on top of the frame, and avoid the feather edge by rounding it, similar to the meeting of side stile and back frame at the top end. This requires a new template. Otherwise everything is the same, although the pegged tenon will be kept, but it will have to be a little longer now because the stile in not inset.
The new template for the side stile is made and one stile is cut from it.
The new, shortened seat back is now erected onto the seat pan and final adjustments are made to the cut angles on the support stiles. Because of their depth (45 mm.) the mortices are cut into the frame on the drill press instead of the router table, and matching tenons are fashioned on the side stiles. The joints between side and back stiles, and between side stile and pan frame behind the tenon, is reinforced with biscuits, as in the battery box. All sharp edges are rounded, and the structure is glued together. The glue up is a bit of a nightmare, with clamping of curved surfaces necessary in three planes. You have to have a dry run, and all clamps and blocks at the ready for the real thing.
The key cutting jig (left), and the key slots (right).
After planing.
In the meantime, I have reconsidered the idea of insetting the side stile into the lateral frame member. I think that a rebate to house it back near the rear corner would weaken the mitre joint, especially as the ply is housed in a groove there as well. So, I will mount the side stile on top of the frame, and avoid the feather edge by rounding it, similar to the meeting of side stile and back frame at the top end. This requires a new template. Otherwise everything is the same, although the pegged tenon will be kept, but it will have to be a little longer now because the stile in not inset.
The new template for the side stile is made and one stile is cut from it.
The new, shortened seat back is now erected onto the seat pan and final adjustments are made to the cut angles on the support stiles. Because of their depth (45 mm.) the mortices are cut into the frame on the drill press instead of the router table, and matching tenons are fashioned on the side stiles. The joints between side and back stiles, and between side stile and pan frame behind the tenon, is reinforced with biscuits, as in the battery box. All sharp edges are rounded, and the structure is glued together. The glue up is a bit of a nightmare, with clamping of curved surfaces necessary in three planes. You have to have a dry run, and all clamps and blocks at the ready for the real thing.
This seat back is in
better proportion than the first one,
and it now clears the lagging with no trouble at all.
Both back supports are in place here, and the rounding has begun. The striping of the back ties it in with the box.
Both back supports are in place here, and the rounding has begun. The striping of the back ties it in with the box.
While that is setting up, I can get on with the other seat, whose box has already begun. I have abandoned the idea of housing the refrigerator in the box of one of the seats. They will both house batteries only, or perhaps some sort of tool kit as well, so the design does not have to be altered for the second seat. At the rate I have been going with the first one, it will take me most of the rest of this month to finish the second one, so I have moved the other tasks, which were set down for February, into March. But, as an inducement to allow the other half of this boat-building team to make her contribution, I have had foam cushion inserts made to fit the forward seats. Hopefully, they will be upholstered in short time!! Incidentally, the types of foam vary according to their intended use. The seat pan uses 65 mm. of high density foam, whereas the back can get by with 55 mm. of medium density. On the rear seat, where the passengers can luxuriate a bit more, I will be using 100 mm. on the pan and 75 mm. on the back.
The foam cushion inserts for the seating.
The start of the
varnishing of the seat brings out the mahogany colour again. The Hoop
pine needs a coat to mellow it too.
A first coat of finish on the mahogany only.
A first coat of finish on the mahogany only.
In the midst of all
this attention to the front seats, I occasionally think back to the
original plan for this boat, which called for a simple bench seat like
the rear seat, which was to be attached to the D bulkhead. That
bulkhead no longer exists in my boat, and if it did, it would entirely
cut off the rear occupants from the forward ones. But it would have
made for simpler woodwork! Never mind. The look of this eminently
functional seating arrangement is pleasing to me, so it all boils down
to the essence of the exercise: why build a slipper launch? Style.
And it was style which brought me back to earth with a thud when I put the finish on the Hoop pine. Somehow it had become impregnated with a grey colour, possibly a fungal contamination, while sitting in my garage. It was not obvious when it was raw, but the first layer of finish showed it up as a terrible smudge which was unacceptable, especially against the relatively clean look of the pine in the box below it.
The contaminated Hoop pine of the seat back.
The colours in the photo do not fully show the extent of the problem.
And it was style which brought me back to earth with a thud when I put the finish on the Hoop pine. Somehow it had become impregnated with a grey colour, possibly a fungal contamination, while sitting in my garage. It was not obvious when it was raw, but the first layer of finish showed it up as a terrible smudge which was unacceptable, especially against the relatively clean look of the pine in the box below it.
The contaminated Hoop pine of the seat back.
The colours in the photo do not fully show the extent of the problem.
The
options were to mask it with a "milk wash", or to cover it with a
veneer. The "milk wash" was chosen because of its ease, although I have
never tried this sort of thing before. If it failed I could always go
to the veneer. A wash of cream coloured enamel mixed in with some of
the varnish was applied over the top of the first coat, and the result
seemed to be acceptable. There was certainly a loss of depth in the
finish, but there was enough translucency to obscure the grey smudge to
a level where it would not be noticed. Another coat or two of straight
varnish should fix it.
After the milk wash.
Before and after views.
The first set of glorious cushion covers is made.
After the milk wash.
Before and after views.
The
jewel in the crown of this seat is the cushion covering. I have gone
with the totally impractical off-white colour of acrylic canvas, with
green piping. These box cushions are a bit of a challenge to get right,
and the other half of the team has spent a day on each of them. Two
more of these simple ones to go, and then the rear seat cushions. But
after this amount of work, heaven help anyone who stains one of them.
But in the end, the impracticality of the slipper launch has to be
matched by its furnishings, and the dedication to the cause has to be
shared by the team - even the conscripts.
The first set of glorious cushion covers is made.
For
the rear seat the back cushion foam proved to be too much of a
challenge for the cutters and a very rough curve on the top required a
layer of wadding to be glued to it to smooth it out. The covers should
take care of any bumps.
The rear seat cushions, with the back one rising 80 mm. above the coaming. (This photo was taken in April '09, hence the rear deck).
The rear seat cushions, with the back one rising 80 mm. above the coaming. (This photo was taken in April '09, hence the rear deck).
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127.
Locating the Battery Boxes
The boxes here are merely sitting on the carpet.
The boxes here are merely sitting on the carpet.
Now
that the seat position has been confirmed, and there is no conflict
between the turning circle and the lagging or steering wheel, the bases
which contain the batteries have to be fixed onto the cockpit sole.
They could just be left sitting on the carpet, held there by the weight
of the batteries, but for stability when towing I prefer to have them
fixed. The question then arises as to how the carpet should be treated
in their vicinity. I am going to cut squares out of the carpet so that
the boxes connect directly with the ply of the sole, but I want to
continue the treatment started with the kickboards, where the carpet
sits under the edge in a purpose made rebate. I could cut a rebate
around the bottom of the boxes to house the carpet, but that would ruin
the symmetry of the dovetails on the bottom rails. Instead, I will drop
the ledger strips for the box bottom down by the thickness of the
carpet.
Small right angle brackets will be screwed from the bottom rail of the boxes through the sole to the underlying floors, and they will pass through the ledger strips and the box bottoms, concealed inside the boxes.
In this manner the carpet will not show any ragged edges where it meets the boxes.
Work progresses on the second front seat, and the slide is installed.
Slide, swivel and seat bottom installed.
Second seat pan is enclosed in its frame.
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Small right angle brackets will be screwed from the bottom rail of the boxes through the sole to the underlying floors, and they will pass through the ledger strips and the box bottoms, concealed inside the boxes.
In this manner the carpet will not show any ragged edges where it meets the boxes.
Work progresses on the second front seat, and the slide is installed.
On
the passenger's front seat I am making a small change. The swivel will
not have a lever; it is operated by friction alone. It does not matter
much if the passenger swivels by chance a bit, and it will make the
seat easier to manoeuvre from behind if there is no lever to be
released. In every other respect the mechanisms are the same. The slide
seen above is not necessary for the seat to clear the steering wheel,
but to allow it to be brought up towards the picnic table which will be
erected behind it, just as the driver's seat can.
By the way, I was lucky with this slide. All the bolts were imperial, as were all the nuts. The device was in good order, apart from some rust in the "stainless" steel!!!
By the way, I was lucky with this slide. All the bolts were imperial, as were all the nuts. The device was in good order, apart from some rust in the "stainless" steel!!!
Slide, swivel and seat bottom installed.
Second seat pan is enclosed in its frame.
The second seat is
sitting a little higher off the ground than the first one. It turns out
that the swivel without the lever is thicker than the swivel with, so
everything sits about 8 mm. higher. Luckily, there is enough spare
thickness in the wooden mounts to be able to cut them down and equalise
the seat height., but that means that the mounting bolts will protrude
further into the pan. They will have to sawed off level with the top of
their nuts: great fun with stainless steel!
With half a day spent on doing that job the progress of the seat itself is slower than I would have liked. But it is nearly ready now.
With half a day spent on doing that job the progress of the seat itself is slower than I would have liked. But it is nearly ready now.
From here on it is
only a matter of reproducing the driver's seat and installing the
battery cable inlets (two on the passenger's side) before leaving the
cockpit for work on the deck. That is set down for March, although I
don't expect that it will be finished within a month. I am still
waiting for the electrical components in the motor compartment to be
hooked up, and then the forward subdeck, prior to the decking proper
being commenced. I think that two months or more will be needed.
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