Clearance between parts?

I’m working on a small model that has one part that slides into another.

As you can see I have the opening at 7/64" and the part that would slide into it is also 7/64". I’m thinking it would be best to figure some clearance between the two parts but I’m not sure how much.

Is there some kind of industry standards I can look up and follow when building such models?



I’d say it depends?

In part the answer will be based on Use, Materials, and how you intend to manufacture it.

As tolerances get tighter, manufacturing precision increases. This looks like it might be going to a 3D printer of some variety. IF SO, you might run a couple of test prints with different tolerances, and compare the differences. (use a set of calipers to measure with.)

The answer in this case might come down to the printers precision, and how much material shrinkage occurs. with the shrinkage business being based on wall thickness, and material choice. There are just a lot a variables in play, and the ultimate answer is obviously to go with what works best on your particular 3D printer… which of course I say at the risk of assuming perhaps too much.

As far as references… maybe take a look at the ‘Machinery’s Handbook’… or something similar.

It’s a nice single volume stop for a wide range of topics which I think are well suited for anyone who’s looking to gain an insight into good manufacturing design.

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Like Jim said, there are a lot of variables to think about, but a good starting point is 0.5mm total clearance.

This book is a great reference:

I would second this. If you are printing yourself, I would try printing a slice of the parts with varying gaps. Depending on the material you are printing in, it might be easiest to print a section sand down the “inside” piece until it fits, then measure the sanded piece to see how much smaller it needed to be to fit right.