As the title says. I’m new to 3d printing and I’m looking for tips on how make two parts fit together nicely. I’ve read 0.4mm clearance between the two parts modelled together is a nice rule of thumb.
It depends on your specific case, of course. That 0.4mm is indeed a good rule of thumb. But also, assuming you’re dealing with FFF-printed parts, generally if the two parts slide together along the layer lines, it’ll feel just a little looser than if they slide together perpendicular to layer lines. That’s just due to the ribbed texture inherent to FFF printing. Though printing at smaller layer heights will reduce that effect and also make the parts fit just a little looser over all.
Aside from that, probably the best advice I can give is:
- Measure/calibrate for dimensional accuracy. [Here]'s a random article on the topic that looks pretty good to me.
- Prototype. Print once, if it doesn’t fit right, adjust the model(s) and print again. Filament is pretty cheap, really. Also, depending on your situation, you might benefit from doing quick test prints just to see how well it fits. If the whole print is going to take 8 hours but by spending 30 minutes printing just part of the final product you can prove you’ve got the dimensions right, it’s probably worth it to do the 30 minute print.
- Use elasticity to your advantage. Make latches or attachments that snap into place. That’s useful whether the parts are meant to go together once and never come apart or connect and disconnect repeatedly. Another use for elasticity is if you need two arms of one piece to friction-grip another rectangulat piece, angle the arms inward just a degree or two. One word of caution, though. It can be really easy to overestimate the flexibility of PLA. I’ve ended up once or twice with some pretty hard to open latches.
You really aren’t giving us enough info there mate.
“Fit together nicely” doesn’t explain what yiu are trying to do exactly. Sketching out what you are trying to accomplish wouod be rather beneficial.
I was just looking for general tips that could apply to wide arrangement of situations. This post was more to the get the conversation going in this community. I have a few ideas I have yet to test out and when they don’t pan out I’ll make a post.
Probably not what you are looking for: I recently had to cut a part in two, because it wouldn’t fit the bed. PrusaSlicer has a nice feature where you can add connectors to the cut. I then used a 2-component putty to glue them together and sanded the overflow afterwards.
I typically model for 0.5mm tolerance between firm fit parts.
Before you can bank on this, you need to see how tight your tolerances are on the printer. I used the Maker’s Muse tolerance test device to figure out what my printer could achieve.
https://www.makersmuse.com/clearance-and-tolerance-3d-printer-gauge
It’s worth the $2 for the model…