Marcus,
I wouldn't be worried about the stability of this wood at all. The cell structure has broken down so completely that it really doesn't behave much like wood anymore. When I glued the lid up, it was in wind (twisted). I place a damp towel over it, and within 15 minutes the damp showed through on the other side of the lid!!! I clamped it in opposite wind for a few weeks and flattened it out, then dried it (workshop, then garden, then bedroom, then conservatory). At no stage did it expand or contract. The breadboard ends remained perfectly flush with the main boards.
So, I think the boat nails could work. Could you give me an idea of the diameter of the head? I wonder if they might be too large for the small scale of these hinges...... I also wonder whether to just use the nails, and not do the roving (it could look a bit visually confused under the lid). If I didn't rove, then I would have to glue the hinges in place.......but that's OK because of the stability of the sycamore.
Also, where do you get hold of boat nails?
Devonwoody,
I have some other boards with some amazing copper-coloured rot holes in them. Some of the turners told me about a filler you can get that is made from brass filings in a clear gel, and this should make an beautiful repair job!
Mike