Door Catch for 2020 extrusion

thingiverse

I've been using a hair elastic around the door handles to keep the doors closed on my 3D printer. I wanted to incorporate some door catches that fit within the space of a 2020 aluminum extrusion, since that seems to be the most common use case for printer enclosure doors. I based this on someone else's existing design (site is currently broken so I can't reference a remix, but it's Thingiverse item 4721582) which was WAY too large for my needs. I made the dimensions so that these catches constantly pull on the door while they're closed, to prevent rattling. My first test was in PLA, and it works fine. I don't know how long it would last, but I've been playing with it for days as a fidget toy by my desktop and it still works. I wouldn't expect PLA to retain its springiness inside a heated enclosure, though. The ones I installed in my printer are nylon (copolymer of 6 and 6,6), and they've been very reliable so far in my heated enclosure. I open and close these doors very frequently. Just make sure you let them cool COMPLETELY after the print before testing them. I printed these with an 0.6mm nozzle at 0.3mm layer height for added strength, they don't need to look pretty. They're designed to be printed pretty fast, with curves on almost all the X/Y plane. No supports needed. Holes sized for M4 screws, though M3 should be fine. The female clips need 20mm screws, either button head or cap screw, that go into T-nuts in the extrusion. Washer is optional but recommended with M4 screws, but required with M3 screws. The male clips need button head screws with the heads on the clip side and nuts on the outside to ensure that the clips can click into the female clip without interference. Cap head screws are too tall. Screw can be M4 or M3. Washer on both sides is optional but recommended with M4, required with M3. Screw can be any length, I used 8mm long screws and it was perfect for my 1/8" thick polycarbonate doors. My printer needed 4 pairs because it has 2 doors that close against each other, but I think most printers would only need 1 pair. Included step files for each clip for including into existing printer designs, and a full Fusion 360 file for those who want to improve the design.