Prolific maker and product designer [Eric Strebel] has years of experience making reusable mold boxes for silicone and resin casting. He’s always used 3/4″ plywood before, but it comes with some problems such as inaccuracy, screws that eventually slip out, and no room at all for expansion. Now [Eric] has decided to devise a modular mold box system that’s so awesome, it’s even stack-able. Check out the design and build process in the video after the break.
[Eric] took advantage of additive manufacturing and made fancy trapezoidal walls with recessed bits that allow for the magic that this modular system hinges on — a handful of M6 socket cap screws and matching nuts for tensioning. Once the prints were ready, [Eric] pounded the nuts captive into the walls and marked fill lines every 10mm. As usual, [Eric]’s video comes with bonus nuggets of knowledge, like his use of a simple card scraper to clean up prints, smooth the sides, and chamfer all the edges.
If you want to mold stuff like concrete and plaster, you may be better off using flexible filament.