Step by Step #8

Now would be a good time to paint the sub-assemblies, and doing it this way saves a dust-sheet on the floor beside grovelling around at that level. And you can have them any colour you like so long as their black.

Step by Step #7

The centre-deck is assembled using the self-same techniques, and in this case foam sheet is applied to the underside. The format of the foam panel is identical to that in the pontoons and between them they displace sixty pounds (27 kilos). This is easily calculated in metric viz. 42 x 87 x 2.54 cm or 9,281 cubic centimetres apiece. No, it's not going to be the world's largest cruise-liner but yes, it's expected to float.

N.B. in the scheme of things each of those spars is supposed to be identical in length at three feet. One reason for a re-build at a slightly reduced size ~ aside from material constraints ~ is that it can then be toted on the roof of the car instead of trailered. On the vehicle in question the distance between the roof-rails is three feet, so the overall width of the craft has to be just that. In view of the fact that the hydroskis overhang the pontoons by an inch and a half, the net effect of this is that the cross-spars have been reduced by around five inches. 

Step by Step #6

With the foam in place and leaving just one side of the pontoon laminated in view of its oversized thickness, run a filet of silicone around the edges. I've used black here because that is the colour of the spray-paint we'll be using. You could of course use a glue to fix these components, and I use silicone only because (a) it's cheaper and (b) it allows fast-builds to be pulled apart and modified as part of a fast-prototyping effort. 

Now to build the second pontoon, simply rinse and repeat...

Step by Step #5

Before popping the foam into the void in the frame, run a seam of silicone around the margin to secure.

Step by Step 4

Here's my re-used PIR insulation being cut to fit the void in the picture-frame. It is 25mm thick, so the pontoon floats can only be skinned to one side. 20mm sheets are available, in which case we could apply laminate to both sides of each pontoon.

Step by Step #3

Fix the laminate to one side of the frame to form a shear-web. To avoid measuring the screw-holes, simply park them in the middle and repeat the process.I've secured with a dozen screws that were hanging around the workshop like a bad smell.

Step by Step #2

Draw around your sheet laminate, which here is leftover three-ply 1mm hardwood that has proven remarkably durable. A tragedy of chopping down every tree in sight is that we'll lose varieties of timber with extraordinary qualities, along with the experience of using them. But don't worry, in the event of apocalypse we'll still have smartphones to hit each other with, and EVs to live in.

Step by Step #1

For testing the boat as a straightforward 'flat-cat' without provision for lifting motors, we shall build a truncated version together that is curtailed at the end of the pontoon floats. Follow me through then as we work together to build the revised prototype.

You can build at metric scale or else imperial as used in the US and UK, converting the following feet-and-inches like so to metric measures: for 6', 3' and 10" sub 2.0, 1.0 and 0.25 metres (and use 2.40 or 2.50 metres to sub for 8' in extended versions).

All of this is dictated by suppliers in the US and around the world, supplying in either multiples of metres or else of feet. Crucial to the build of a shorter prototype is the fact that carbon fibre tubing often retails at 1.0 or 2.0 metres at a maximum and we can expect to migrate to exotic materials of this kind to reduce weight further.

Meanwhile extruded plastic tubing that is manufactured in the UK is retailed at either 1.0 metre or 3.0 metre lengths, with a considerable surcharge for the latter to account for the fact that parcel distributors here apply extra costs to carrying anything beyond a metre in length.

To begin, however, cut your longest spar to 6', another to 3' and two more to around the 10" mark depending on whether you've used rough-hewn timber (1" or 25mm) or PAR (3/4" or 21mm). I've gone with the latter here, and used 305mm minus 42mm as my guide.

We now use the four spars to build a 'picture frame' toward the rear of each pontoon, driving a screw in at each corner to secure.

Apres Ski

None of you have been asking how to tote five metres of uPVC architrave ~ used here for hydroskis ~ in the average station-wagon.

And so you should have, but here's how to do it in a station-wagon of below-average dimensions... by temporarily coiling it up and taping the ends. Note too how the upper spars can be slotted in too, at a length of 2.40 metres or eight feet.

Ignore the plasterboard, however, which has no place in boat-building.

The skirting (or architrave, depending on whatever floats your boat) has a chamfer that will be set on the outside of the turn, and of course the right way up. Despite the fact the product is advertised for internal use, be assured I've been on to the manufacturer to ask whether it will sustain fifty-knots on seawater as a part of our risk-assessment:

https://www.swishbp.co.uk/index.php/products/trims/skirting-and-architrave/

Wooden Warfare

In the news recently, reversals in the conflict in Ukraine involving incursions deep into Russian territory by one-way attack drones. I'm rarely taken seriously in the UK, using as I do foam and timber within a culture more used to sitting on it's ass watching F1 cars built from carbon-fibre racing in an effort to accelerate global warming.

YouTubers in the US tho' often rely on Home Depot to prototype wholly new designs made possible by advances in electric motors. And this combination between modern 'soft' tech and traditional 'hard' ware is being used to advantage in places where conflict is accelerating progress, not least in war: for what seals the success of such drones is combining their use with AI that figures out how best to route them to avoid anti-aircraft fire.

For the drone above is responsible for any number of incursions and is made in what used to be wooden-furniture factories. Short of materials during WW2, the UK turned to wood to build the 400 m.p.h. Mosquito that was made by emigre Italian furniture-makers long established in London's northern suburbs. At the same time, the wooden Hurricane destroyed more of the Luftwaffe than the Spitfire, whilst the wooden-winged German V1 was infinitely more successful than the V2 rocket at a 25th of the cost.

I recently visited a factory that produced bumpers for Bentleys in view of the fact it was closing down. The machines to produce injection-moulded bumpers are half the size of a house and as heavy, and emblematic of the fact that at least in parts of the world not at war we needn't produce anything for ourselves, nor know how to do so.

But the evolutionary biologist Richard Dawkins has recently speculated that technical progress may now be outstripping our ability to adapt to changes that follow, given that prior generations could have expected to live essentially unchanging lives. Aldous Huxley wrote that 20th century citizens were effectively the first to experience speed per se ~ we could be the first to experience the unimaginable speed of change.