How to create threads

Is there a way to create threads with the revolve tool, for example if I needed to make a 1/4-20 thread what would be the set up I would need to get an accurate copy of the threads.
This is the best I have come up with so far.


I used a download from McMaster Carr and turned on section cut aways and made a copy of the pitch at least I think that’s what it’s called, this gives me a starting point for the revolve tool image
Doing it this way gets me almost there, but when it comes to threads I would think you would have to be exact.after I did a subtract and lined it up with the original bolt this is how far I got.
Are there any proven dimensions to use with the revolve tool to create threads that are accurate .
When using the revolve tool what do the amount of the angle mean, is there a chart that would have this information. I’m not a machinist so all can do is try to match the original.
Any help would be greatly appreciated.

Go to the tutorials and watch the tutorial on creating helixes… the splash shows a shock absorber and spring. Making threads is just like making the spring… except you wand the windings tighter.You just draw the profile of a single thread, with the height of the profile equaling the pitch. For example, for a pitch of 20 threads per inch, draw your profile 0.05” tall. For a 1/4” diameter screw, set the point of the thread profile 0.125” away from the Z axis… then use the revolve tool to determine the number of threads- setting the height as the number of threads times 0.05…
i.e. For 1 inch of thread, you will input 360 Times 20 = 7200 degrees.
You can then extrude the shank of the screw and its head and union it all together.

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Or, you could just go out to McMaster-Carr’s website, find a screw with the thread you need, download the STEP file, and load it into Shapr3D. You can then manipulate it from there.

Where did you get the 0.05 profile height. Is that from the 20 threads per inch. Is there a chart that would show the different profile heights for the varying thread sizes. I understand the reason for setting the profile at 0.125 from the z axis so it will equal a 1/4”, and the 360 is 1 complete revolution x the 20 threads an inch. The only part that I don’t get is were did the 0.05 profile height come from. Once I get all the pieces then I can create different sizes like 10-32 & 4-40.

I had mentioned before that I had downloaded a screw from McMaster Carr but it didn’t work exactly,

Thank you for your help

Threads are listed in TPI- thread per inch. Divide 1” by 20 threads and you get 0.05”.

For 32 tpi- 1/32=0.03125”
You don’t want the thread profile to cross itself- as that might cause issues… so be precise, or err on making the thread profile just a tad shy so that there is a teensy gap and fill the gap by extruding or revolving the central shaft of the screw to slightly cross the deepest part of the thread pitch so it will union cleanly.

Oh- and when you make a screw you like… save it as a separate file you can archive and import anytime you need that size screw.

Thanks for the help, now it’s started to make sense in the real world situation.

I am trying to do similar. I watched the threading video on the water bottle to figure out how to make a custom screw (I am trying to modify a glass plate clamp). So making the screw, it prints fine. However, when I made a test “Screwhole” with the corresponding threads to screw into, when it prints out, I am not able to screw them together.

I will attach images

I have also tried widening the spaces between threads, so instead to 3600 over 8cm, tried 2700 degrees over 8 cm.

@Past1320 if you want to print both the screw and the nut I suggest you to stick with one pitch
If you want to print either then read about Iso measurements and pitch for your non printed part

Correct Pitch can be hard to add in shapr3d

What technology are you using for printing? Based on the scale shown in the workspace is it going to be a kind of an M4 thread?

I am afraid you are not able to screw them together because the nominal tolerance of your model is way smaller than the accuracy of printing technology you use can provide.

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Thanks for quick replies!

the pitch for both the nut and screw were I think .5mm each. They were the same I thought? (I copied and flipped the sketch)

I am using a filament based not resin based printing technology. I believe your right it may be more printer error. I downloaded M3 screw and nut samples from McMaster site and printed them. Still an issue getting it to work.

After looking into it more, anything smaller than an M5 internal thread may be difficult to print with filament

So looks like its a problem with the printing technology for the given size.