comakingspace
Create DIY clamping claws with counterholders and cam levers - as shown by Marius Hornberger
https://youtube.com/watch?v=bpJyqLoqV04 https://youtube.com/watch?v=O-rqf4uSXRE
Before these claws will be useful, #51 needs to be done as well. Therefore, the issues should be worked on at the same time.
We should at least cut a few of these clamps (and counterholders) before preparing the new board, otherwise we'll have to damage it by screwing into it right away. I'll check our available Multiplex tomorrow but we may need to buy some - Marius Hornberger uses three different thicknesses, looks to be between 8 and 24 mm.
EDIT: unless we make the clamps by hand of course, then the order is not as critical
We decided to go with the "big" version of the clamp so we could have 90 mm hole spacing, hopefully keeping the board more stable due to less material missing.
I scrolled one clamp out of 6 mm plywood but it shifted out of the horizontal plane when tightened. Not sure if that was because the clamp or the spoilboard needs to be thicker or because the two "practice holes" we drilled for #51 were in a (very) uneven section of the spoilboard...further testing needed!