Smoothing castable wax before casting

General Discussion
1

Hello.
We run a jewellery program at a college and we are new to printing jewellery. The issues we are having are trying to use the traditional techniques to smooth the printed castable wax.
we would normally smooth it with tool and a mineral spirit of some sort. However this technique doesn’t seem to work and we end up having to grind and polish quite a lot of the surface to get a smooth finish.

See photos for reference. The Silver ring has been polished on the right side and is still raw on the left. However it is quite rough and pitted. The wax ring however is not rough or pitted.

20170525_133256.jpg720×405 94.3 KB

Any help would be appreciated.
Thank you

2

Are you casting your printed parts as shown in your picture? That ring does not look fully postcured, which our material requires in order to bring it to full castable properties. Pitting is often caused by insufficient curing, as the finished piece should reflect the surface finish of the printed piece.

Also, we recommend rinsing in IPA, allowing the part to dry, and postcuring as the only finishing steps. Mineral oil treatments can also sometimes cause casting issues.

1 Like
3

Yip, now that I read up on post curing we missed a massive step. I’ll try this.
So if I go abouts curing it as suggested is there any further way of smoothing out imperfections before casting?

4

Once postcured, if there are any surface imperfections these can be gently filed away by hand. Postcuring will make the resin more tough and brittle, which means it will be somewhat more susceptible to breakage but will be tough enough to withstand light hand filing.

5

Fantastic. We’ll give it a go. Thank you

6

due respect, but it looks to me as there’s a casting problem, and not with printing

7

I would alway add the sprue, or at least a stub, to the print. This means that the caster can’t put blobby bits of wax all over your piece and save you time cleaning up.

8

Thanks for the feedback. This is all new to me… I am not a jeweler. I am one of the instructors from the digital arts program trying to figure this out on behalf of a jewellry instructor. I will pass this on to them and see if they know what you mean.
Yes there are major issues with the casting process. They apparently don’t have a high end casting setup and aren’t able to get the silver into the small area.
Yes the sprue came up in conversation and it’s a great idea.

9

You should be sure to follow the Formlabs burnout process. Otherwise, ash inclusions.