Adding threads to your 3D prints is a life-changing feature, but obviously there are a lot of trade-offs and considerations when deciding on how to go about this exactly. Between self-tapping screws, printed threads, heat inserts and a dozen other options it can be tough to decide what to go with. In a recent video [Thomas Sanladerer] runs through a few of these options, including some less common ones, and what he personally thinks of them.
Confounding factors are also whether you’re printing on an FDM or resin printer, what size thread you’re targeting and how often the screw or bolt will be removed. The metal heat inserts are generally a good option for durability, but when you have big bolts you get a few other metal-based options too, including thread repair inserts and prong nuts. Tapping threads into a print can also be an option, but takes a fair bit of patience.
Slotted nuts can be an idea if you don’t mind carving a space into your model, and the comments dove on embedding nuts in the print by pausing during printing. Ultimately [Thomas] really likes to use a type of self-forming threads with just three protruding sections into the hole that the bolt taps into, which reduces the stress on the part and works well enough for parts that only have to be screwed down once or twice.
Me unga bunga caveman. Me cut small hole and use regular M3 screws as redneck self tappers. Ug print many things like this
For my taste cutting M3 into printed plastic is a lala-good-bad-job-random-pain-thing.
I love the riveted nuts (right most at 7:25). They are cheap, easy to design around and do not need any tools, just pull them in with a screw and a washer.
If you own a KLIPPER printer, they can be used very totally easy inside out: just design a hole big enough for them, slice the thing and look for the layer number to insert them with slicer preview. Then open your .gcode file, look for the layer and add “PAUSE” into it. Surprisingly, the print will stop, head moves away and the printer will wait forever until you press “continue” on its screen.
/me loves that stupid user compatible stuff.
Same here honestly. I just under size the hole I make in my part a bit and pretend that my machine screws are self tapping.
Granted, I’m not relying on the strength of these too much, as usually I’m attaching a lid or some other non-stressed connection.
Just curious….is that better than self tappers, or just because you don’t have self tappers to hand?
I have no experience with 3D printing, but for wood, where I need to attach a machine screw I usually use what we call a Rampa nut (aka a threaded insert). But for stiffer woods if the bolt is long and doesn’t need to be reattached and not need to support too much force, you can tap machine screw thread into wood quite well and just thread into the wood.
Meh.. embedded nuts are easy enough to design around and cost-effective, otherwise heat-set inserts are my go-to for finish and production-quality stuff.