The clamps for the frame and the frame tubes

They have been made earlier, but not documented yet: the HDPE clamps for the cross braces.
When my wife went to the Hanos to get food for her cooking business I asked her to pick up a HDPE cutting board. Nice colour, isn't it?
The stuff is really easy to work on. Use a reciprocal saw to cut it, and drilling really is easy.
I could not get a 19 mm drill, and I did not want to spend big money. So I made the crossbraces out of 22 mm sleeve tubing. 22 mm speed drills (those flat drills for wood) are easy to obtain, and work well. The final deburing is done manually with a sharp knive, and the result is:


I also made the side tubes for the frame, a quick and easy job.
These are the times that I really love to have a lathe and a milling machine.

It looks like a boat, almost

With bow and stern shaped it is time to turn the hull over . So I took it of the skinning frame and put it on the table.
I contrast to the pictures by Tom my hull does not keep shape without the sponsoons inflated. Another problem is that I made the hull material slightly on the short side, so I tried to use clamps at the bow and stern tubes. These do not hold, so the bow and stern tube slide out of the hull. I finally solved this by using small screw clamps.
The loss of shape probably is due to the fact that I use the sewn sleeve method. The hull now essentially is a flat piece of PVC. With PVC sleeves the sleeves are more rigid and keep the hull in shape. Next step is putting in the sponsons. I use masking tape to tape the sponson to a side stringer.

And then I fold the sponson and insert it into the sleeve:

After some fiddling all sponsons are at the correct locations.
And this is a horrible image of what it looks like with the sponsons inflated and the hull taped.
Taping is another subject of importance. I tried two brands of duct tape, two types of masking tape and packing tape to keep the hull in shape. I wanted to avoid glueing straps over the hull.
To no avail: ALL tape lost its bond with the hull after some time, exept the packing tape. Instead, the packing tape just broke, and left a horrible glue residue.
In the end I used so brandless masking tape (P&P, says the roll) that has the best bond without leaving much residue. But the glued strips are required.

Fitting the skin

The skin is put onto the skinning frame, ready to finish bow and stern.

Using clamps the skin near the ends is clamped to the gunwhales to have it tightly on the frame. The skin is marked with masking tape for a proper overlap just around the frame tube and cut to identical lines on both sides of the hull.

Some temporary pieces of tape hold the PVC in place to mask the area to be glued.

After application of glue the skin again is taped in place, and heat and pressure are applied to bond the PVC. It really helps to have the PVC properly taped at the correct location before trying to achieve a bond.

The area near the bend is a bit difficult and needs some smal cuts. These will be covered with a small patch later.
The final result:

glueing bananas on the skin

The sponson sleeves now are ready to be glued onto the skin. Regretfully, no photographs of this building phase.
I put a double layer of Helaplast on the bananas and the skin, using masking tape to mark the area to glue and to allign the bananas.
I used an iron to heat the sleeves and put pressure at the same time. This works quite well for flat surfaces.