Material choice other than Grey Pro

Looking for more shear strength than Grey Pro.
I have small gear with a triangle output shaft that I’ve been printing in Grey Pro, the shaft is failing. Its an existing part in a larger assembly so design changes are very limited. Shaft is roughly 3mm in Dia. Any material recommendation other than Grey Pro that is going to allow the shaft to be stronger and not shear under load. Maybe Rigid 4000 or Tough 2000? Part does not see UV or heat exposure. Last resort will need make a separate metal output shaft.
Form 3+

Personally I think rigid is just to brittle for all that, Tough 2000 is great and for sure better than Gray pro, if you have it on hand than I would try it. I use all the time for larger stiffer parts. For this I would use Durable resin, it has tiny flex to it and it should be plenty strong.


Really depends on the definition of “load”.

I’m pretty fond of Tough 1500, which isn’t quite as brittle as Tough 2000, which is much less brittle than Grey. Not sure why you started with Grey, it’s not really an engineering resin.

I have printed parts like this, and had similar failures even with Tough. The solution I came up with was to print the component with an axial hole, and then run a small cap screw through the hole so that there’s a steel shaft to help reduce the stress on the printed part. An M1 screw and nut would probably be workable given the size of your gears.


I like that solution with the M1, will try that. Only on hand was Grey Pro, I’m going to add Tough 1500 and Durable to my library and try it.

Hey @Ciye,

I think the other answers have been pretty helpful suggestions, and always want to advise trying our Resin Selector tool that will ask questions about the use-case and then suggesting appropriate resins for you. I hope this helps!

Agree with Randy. Tough 1500 has worked very well for me.

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Personally, I use Tough1500 for most parts that I print. They hold up great over time, and resist impacts from drops very well (I make lots of models and miniatures so this is a big selling-point for me).

For a part like that I would personally recommend Tough 1500 or Tough 2000. Be sure to do a good job cleaning out the resin from in between the teeth before you cure, as that can cause some binding and unwanted forces on the gears.

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