Originally Posted by Paganferret
Does the exact position of the glued board matter as long as it does the job of holding down the inflatable keel?
There are some hypalon tabs in the boat that look like they might have been glued to a board in the past but I can't be sure.
Any idea of the thickness of ply that this needs to be as well?
Hi Paganferret, that board that is normally glued in is the thrust board. It's primary purpose is to ensure that the 3 floorboards aft of it will fit tightly between it and the transom when those floorboards are pushed flat and the stringers are installed. The tight fit puts the fabric under tension to help keep the inflated hull more rigid. Older zodiacs use a similar system.
The thrust boards do tend to be a real PITA however, because over a period of time they do tend to come loose, and regluing them properly
is complicated and laborious. The solution that the RNLI guys use with their Avon IRBs is to remove the thrust board altogether and located 2 marine turnbuckles (they refer to them as bottlejacks) between a single plywood board (that replaces the 3 aft floor boards) and the bowboard. there is a small gap between the boards where the thrust board would have been. I will see if I can find any pictures of this setup. Maybe one of the RNLI fellows will post up.