Hi, just thought i'd share back to the group an option for plate mount that seems to work (i haven't been able to break it.. yet).
I've been working on getting a plate mount fitted to a surfboard for strapless kite-foil, foil-surf and normal surf. The idea was to make a foil surfboard with two longboard boxes that could also double as a Duo surfboard (read about it here: http://comparesurfboards.com/reviews/al ... ard-review). But after paying too much for two FCS boxes and being surprised at how heavy these boxes are, I decided to do a test-board first - a cheap board for testing out foil position and that I could ding up in the learning process.
I set a deep SS nut (https://i.ebayimg.com/images/g/nM0AAOSw ... s-l300.jpg) on top of a washer inside a plastic cap, using carbon twisted around the nut and inside the cup like this:
This goes into routered holes into the board with a balloon mix. I took the foam out all the way to the deck laminate for added strength. Like this:
I then masked off two strips on the board (two layers of masking tape makes final sanding easier. Then over the caps i put a bi-ax patch and then a UD strip with some balloon mix over all of it. I find the holes using pins (can be pulled out once the epoxy is dry) and let it set for two days. Then just sand back to a smooth level surface:
The end result looks like this:
I think because the plate is quite wide (the Duo fins are placed 6 inches apart), any sideways force creates a push/pull on the plugs, rather than a moment force like you'd get on a centred turtle box. As long as the plate can't squash the carbon strips on the one side, or pull the plugs out on the other side, it will hold. The added bonus with this setup is, two SS plugs (deep nut, washer and cap x 2) weighs less than half of the FCS box.
I'll still do the Duo board some day, but for now the bolt-in cheapy seems to do the job.