Edit: This is now available in the Free Files area: Mastermind Game With Rack & Pinion Box Latching Mechanism – enjoy!
I’ve been working on a design for a Mastermind game / box. Version 1.3 of the SVG has been shipped to my brother @timjedwards for prototyping fun with his kids and our nieces/nephew when they visit him today, and since he’s usually 'way better with this kind of stuff than I am, I’m anticipating there may be some cool upgrades…but I thought I’d give you a little preview in the meantime. (Because yes, the design will be posted in Free Designs when it’s ready for public consumption!)
I decided to build the game onto the top of a box, the sort that slips down over its bottom half (there’s probably a name for those, but I on’t know what it is), and then I worried about all the pieces spilling if someone picked up the box and the bottom fell out, so I had to think up a way to latch it shut when not in use. Google was no help at all, and even Pinterest failed me this time, but night before last when I was supposed to be sleeping my brain suddenly spat out a fully-formed design, which made it even harder to go to sleep since then I wanted to try it out immediately. (And then I had to get up and go to work with it stewing in the back of my head all day wanting to get out!)
It took a little time, because 1) I’ve been using this project to learn Affinity Designer and 2) I had no clue how to design rack and pinion gears (or any other sort, actually!) It turns out that the online gear template generator has a rack & pinion option built right in, yay!
Anyway, here’s a photo of the locking mechanism, prototyped in PG draftboard. The gear mechanism is sandwiched in the bottom of the box, with a hole cut for access to the finger holes. Twisting the gear sends a tab through slots in the box bottom and top at each end, locking them together. I’m pretty proud of it – and also pretty happy with Affinity’s cog feature and corner-rounding tool, both of which were a huge help on this project!
Gear assembly, exposed:
With box bottom in place: