modify extended-reach VICEGRIPS to accept your rivet bit tools. You will be able to adjust the tension you need by adjusting the VICEGRIP tension

I managed to get a real tight fitting joint with a 4 mm2 copper wire, a 2mm hole and crushing the wire. Wonder if I have to glue as well.
Next to find is a clamp, with a wider range, that allows for broader wooden planks.

Ross,

sounds like a good idea. I will try this and keep you informed.
It will take some time to find molds to form the rivet heads.

1.6MM copper house wire can be pushed through 9MM of pine, if the end is sharpened to a point.

a hobby hand grinder can be used to flatten the ends, like a rivet. It heats up the wood and doesn't have much holding strength

You may have to make your own from copper wire

Willem

SLIGHTLY CRAZY IDEA

2 pins required per joint

send a pin through from the outside, trim to size

send SECOND shortened pin from inside right beside first pin

2 heads are better than one

On mine it was simpler. Inside is not open to view. I modified a set of pliers to hold a pin steady. Pushed it in until it came through the inside frame. Pulled it tight from the inside

In yours, push a shortened, second pin from inside, right beside first pin

What diameter head and shaft do you need?

If you are working the rivet close to the edge of the plank, for clinker-built construction, are you concerned about splitting the plank? My planks were 3mm by 10mm and the 0.9 mm nail was in the centre of the 10mm at 5 mm

Ross, thanks for your answer.
The pins are a solution, but I plan an open rowboat. The rivets will also be seen from the inside.
In real life, the pins are insertet from outside and on the inside of the hull, the washers are squeezed on the pins to keep the wooden planks together. Then the remainder off the pins are cut and then cropped.
The squeezing is not the point, but how to show the rivets from outside and within the hull is the question. The pictures are from the real thing and these are to big.

Willem

Willem

Brass pins and polish (sand after install) the finish off the head.

I used about 900 stainless steel pins in the BLUENOSE hull. It's a lot of work

pin head diameter: 2.1 mm
pin shaft diameter: 0.9 mm