The tripod mount is a rectangle of plywood drilled and counter-bored to take a 1/4-20 "T-nut." That's a top hat shaped piece with a 1/4-20 thread inside, and some prongs sticking up from the 'brim' that get driven into the wood to prevent rotation. It's a common hardware store item used to provide sturdy metal threads in a wooden part. The plywood rectangle is then attached to the camera box with flathead screws from the inside. My failing on that was the screws were slightly long and the tips ended up being sanded down and showing. In the bit of CAD drawing showing in that picture you can see a crude cross-section of the T-nut in the plywood plate.
I actually used brass screws and stainless steel T-nuts which easily accounted for the bulk of my cost (well, and a can of flat black spray paint!), as most of the wood was leftover scrap.
The bore in the sketch would be against the camera body and the T-nut would be inverted and inserted in that hole before the block is attached to the camera, capturing the T-nut. I used two, one on the 5 inch side and one on the 4 inch so I can do horizontal or vertical formats.
Last edited by DWThomas; 12-03-2012 at 11:43 PM. Click to view previous post history.