topic Re: Thread design for 3d printing issue in Fusion Design, Validate & Document Forum

Thread design for 3d printing issue

Anonymous — Tue, 26 May 2020 21:05:08 GMT

Hi,

I am having an issue with the female part of the thread. The thread couldn't be printed near the end/edge of the thread as it transitions into a smaller hole (shown in the picture). I was wondering how to design it to prevent it from happening.

Re: Thread design for 3d printing issue

LeonardoBN — Tue, 26 May 2020 22:29:17 GMT

Hi @Anonymous. Were you able to print well the remaining of the thread?

If you want to avoid supports, you could add a angled transition between the two diameters, like a Chamfer.

Re: Thread design for 3d printing issue

Anonymous — Wed, 27 May 2020 07:41:01 GMT

so I have printed couple of models. the one on left has no chamfer, the right one has, but it is still not turning out correctly.

I also did a pure thread print and it was ok. so i guess it is purely a design issue?

Re: Thread design for 3d printing issue

LeonardoBN — Wed, 27 May 2020 12:26:19 GMT

What filament and layer height are you using? You printed both full and thread-only part with same configurations, right?

I 3D printed some threads in the past. If I remember well, I went up to a M16 thread using a 0.15 mm layer height without support, as I didn't want to give post-processing.

Re: Thread design for 3d printing issue

Anonymous — Thu, 28 May 2020 03:39:46 GMT

i am using 0.2mm as layer height. is that too high?

for the prints, they are all in the same config.

Re: Thread design for 3d printing issue

artemSIV — Thu, 28 May 2020 07:45:44 GMT

Hello. This problem is associated with the selection of layer height for the diameter of the printer nozzle. In the picture I gave an example for a nozzle with a diameter of 0.5 mm and a layer height of 0.2 mm and 0.12 mm. Also, high speed can spoil such an angle. I wish you success.

Re: Thread design for 3d printing issue

GRSnyder — Thu, 28 May 2020 18:44:45 GMT

I believe @LeonardoBN has identified the problem correctly, but you'll need more than a simple chamfer to address the issue. At some locations, the unsupported overhang is so large that a 45 degree chamfer would disconnect the thread from the barrel. I think this is why you're seeing some improvement with a chamfer but still having some trouble spots.

There are various ways to address this, but the easiest and most robust is probably to adjust the outside envelope to remove the 90 degree inset if you can, replacing it with a 45 degree ramp. Then you can print the part upside down (with the thread portion upwards) without support.

Re: Thread design for 3d printing issue

Anonymous — Thu, 28 May 2020 21:25:32 GMT

Thanks very much for the help

Re: Thread design for 3d printing issue

LeonardoBN — Fri, 29 May 2020 00:01:05 GMT

I have to rectify my previous anwser. As pointed out by @GRSnyder, the chamfer by itself will not eliminate all overhand areas. If the original design could be printed upside down, you would need supports only outside, whicj is far better than support touching near thread.

A 0.2 mm layer height should work well for the thread.