How to make bolts and nuts

Hi, I’m learning 3D modelling, I watch video tutorials, but I don’t see any way to make a functional thread and screw for 3D printing.
Is there any function to be able to adapt a M6 or M8 thread without having to count the threads with the revolution function. Thanks

Hola, estoy aprendiendo a modelar en 3D , veo videos tutoriales, pero no veo ninguna forma de como hacer una rosca y tornillo funcional para imprimir 3D.
Hay alguna funcion para poder adaptar una rosca M6 o M8 sin tener que contar las roscas con la función de revolución. Gracias

Veo videos de fusion 360 y tienen una opción de hacer roscas de metrica determinada.


There are YouTube videos on making threads, but the quickest way is to download a STEP files of the component you want from Choose the screw, bolt, or nut, then select the 3D drawing option, then the format of STEP, and import that into your design. Then add or subtract as needed. This gives your design precise and proven threads.

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This does work, to a point.
I use McMaster A LOT myself.

If having the thread modeled to show the feature for dimensions in a 2D drawing, like thread depth etc then yes.

However when printing functional threads, the subtract method doesn’t allow for any thread clearance, which can cause binding. This may or my not be an issue depending on material used for printing, the function of the threaded part, accuracy of the printer and type of printing method, etc.

In some cases you may need to chase the holes with a tap if needed/possible.

However, now that we have non-uniform scaling, you may be able to experiment with scaling a fastener ever so slightly to account for clearance/part shrinkage if it is an issue. I have not tried this yet though.

Just something to keep in mind :+1:t2:

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Nathan, I have not found threading issues to be the case for my prints. Nuts and bolts already take this into account. When I print my threaded objects, (many hundreds), I’ve never had an issue with threads binding from McMaster-Carr downloads. I have when I’ve tried to make my own threads however. I use multiple FDM printers, mostly Zortrax and Ultimaker, or my FormLabs Form3 resin printer. I’ve made many custom aquarium fittings, where thread interfaces are quite critical. I’m uncertain as to why your prints have binding.

Hello, thank you very much for the answers, but the same thing happens to me Nathan, I make the model then the subtraction, I print with PLA+ in an Odin 5 f3 and it always comes out welded or if I do it separately it doesn’t work either.
I attach a video of NCAD which is very good but I did the same but it does not work.

Sorry for my english :sweat_smile:


With ultimaker cura you have the option of 0.03 0.02 retraction but I think that should come as an option in sharp3D in the same style as I saw in fusion360. Which already has the options for standard metrics for the screw and nut threads. The same goes for gears. It doesn’t discriminate anything for printing or doesn’t give that option.
It’s possible I’m wrong as I’m just learning to use the app.

@McD it’s good to hear yours print well, I wish I had some better outcomes.
I’m curious, are you using nuts for female thread features or subtracting male fasteners?

Also, are your fittings course or fine thread?

My binding/mismatch thread profile problems have stemmed from fine thread or smaller fasteners like M4 or M5, but these were for prototyping. I chased the holes with a tap, and eventually the parts were machined from aluminum.
This could be due to some minor part shrinkage, I didn’t look into that particular part much further due to time but I have seen this as an issue depending on the possibilities I mentioned above.
I was using my Anycubic Mono X resin printer in the example above.

Nathan, ah, ok, your trying to print quite small threads. I’m doing much larger threads. 13mm and above. For small threads, I make a hex recess to hold the nuts in place, or create a small hole, surrounded with material and tap the holes. All printed thread have been coarse to date. The resin printer has solid material all around the holes, so tapping is quite strong. My apologies for not realizing the small size threads before.

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No worries, thanks for clarifying :+1:t2:

Just to say, if you use the substraction method with MacMaster, it won’t work, you doesn’t have any “air” between the parts.
Like @McD have said, the gap calculation between the nuts and bolts are made and if you take them separatly, that should work. But M4 or M5 would by treaky anyway, the gap is small.

Hello, I am trying to do the subtraction as you indicate but I always get an error.
If you find or see a video of how to do it, if you can indicate the link, so I can see the technique.

Thank you very much for the McMaster tip. However, reading all the other comments of this thread, it appears to me that people didn’t understand exactly what you advised them to do. I think (please tell me if I am right or wrong) that you recommend to use McMaster bolts to create male threads; and McMaster nuts to create female threads. Which is perfectly logical. Then you proceed advising to use boolean “add” or “substract” commands to properly add these imported threads to the model in Shapr3D. At least that’s why I understand. I see no issue there.

Then I read answers to your main post, but they don’t make sense to me. People say that there is no clearance (“air”) when substracting a bolt from a solid in Shaper3D in order to create a female thread. Of course it cannot work this way! If one uses the male thread of a bolt to create, by substraction into a volume, a female thread, the resulting thread will have ZERO tolerance with respect to the male thread. A male thread is NOT exactly the same as its female counterpart.

May I add that if some FDM 3D printed threads are proven to be too coarse in the end, and the resulting plastic bolt or lid gets jammed or cannot be screwed entirely, they a simple solution is to slightly increase the X/Y size of the female thread by a few percents. Usually 102% to 110% max does the job (110% may be too loose, start with lowest value, print a sample to test it, and increase step by step if necessary). Don’t increase the size of the female threaded model along the Z axis however.


Whether the McMaster threads are sufficient as-is depends on how you’re manufacturing the part. If it’s a plastic part, tolerance really isn’t needed: the plastic will flex and give you a nice tight attachment.

Import a Bolt with your required thread from mcmaster Carr and integrate the thread into your model.

Hi, thanks for the clarification.
Although I still have doubts.
When I make a screw with a nut and I want them to work correctly for a 3D printing of a material such as PLA as you indicate I have to import the part of the screw threads and the MCMaster nut and then make the tolerance.
The truth is that I try and I do not get it correctly or gives me error or problem.
I also checked that in other apps like Fusion360 they already have that part included as a feature of the program.
I think it would be very interesting to have this within the Sharp3D app for the different metrics and not have to do more complicated and laborious things…
I would also like if possible to see how you do it in some video. It would be the best way to learn at least for me.
I uploaded the youtube video of a person who makes nut and bolt but that is not functional and I indicate it in the video.
thanks and sorry for the inconvenience

I created M12 bolt and nut. I create both the nut and bolt in shapr3d as normal. Before I do a subtract, I use scale (x and y only) and scale my bolt to acquire the proper clearance. Once this is set, I subtract to establish the proper thread in the nut. Once this complete, I use scale to put the bolt back to its M12 dimension (x and y). You see the results below. 3D print and the nut screws on the bolt easily. Checking dimensions, the dimensions are within tolerances.

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Most of my 3D printing is done on a FormLabs resin printer. For smaller screws, 1/4” or less, I create a small hole, then tap the threads. I’m rarely, if ever printing both the screw and nut. For larger threads, i.e.: garden hose fittings, I download the component from McMaster and integrate it into my design, and print it as is. This is more difficult to do with FDM printers as the wall thickness is typically thinner, and infill doesn’t support the tapping stresses.

You can also add tolerances to threads in parts by simply upscaling the screws in the transverse plane before subtracting. The thread pitch is maintained by avoiding scaling in the axial direction.

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On Infill, blockers can modify areas to bolster infill areas where threads are.


I have heard of doing something like this, but haven’t done it personally as all my completed models are done in resin. For prototypes I do use one of my FDM printers. What is the technique to add “blockers” for a FDM model?