Cleaning 3d prints

[Malonehan]

Hello all,
We are having trouble with the KeyPrint Hard, they are coming back cracked in the molar area quite a bit, so I'm trying to troubleshoot. One thing I realized is that we were letting them clean in alcohol in an ultrasonic for way too long. KeyPrint says max 5 mins, we were doing well over 10. So, we are cutting that back, but I'm wondering if there is an alternative to alcohol as a cleaning solution, I'm thinking that it could be eating away at the actual appliance and making it more brittle. Thoughts? Thanks!

 

[tuyere]

Alcohol won't harm the appliance if you're using it as per the verified workflow, don't try anything else if there isn't a verified workflow for it (and there usually isn't, our own nightguard resins only specify 95%+ isopropanol). It won't 'eat away' at it or embrittle it if used properly.
It's possible you over-soaking them has been causing issues for you, I'd wait and see if the issue improves. You might also have issues with your design. Or you might want to change products, most people who print nightguards tend to use softer thermoplastic resins, which is much tougher and fracture-resistant. We use keysplint soft and patients cracking printed nightguards is basically unheard-of; keysplint hard breaks at 9% elongation, soft can tolerate at least 110%.

e: Also, what's your post-processing regime? I've never found ultrasonic cleaners satisfactory for first-pass cleaning with these kinds of appliances, something with strong agitation/flow gets the job done faster and lets us keep within verified parameters. We've got 7 minutes with Keysplint Soft, and 4 minutes dirty wash, 3 minutes clean stays within that. We use Form Wash machines, which automatically raise the parts basket out of the wash when the timer runs down, which is very nice for ensuring we don't forget anything in the wash and end up with it out of the verified workflow.

 

[Malonehan]

Thanks for your reply! We currently use an ultrasonic and are trying to limit it to 3 mins in the dirty bath and 2 in the clean, and it comes out pretty nice. The lowest setting on the ultrasonic is 6 mins, and when we originally had the printer set up the trainer said that was fine, but I'm sure that was because whatever material we used then. So we were doing 6 mins in dirty and 6 in clean. My bosses and I were looking into getting a p-wash, since we have a rapidshape printer.
Thanks again

 

[rlhhds]

We use Keystone Hard and Soft with great results for both materials. Following the IFU is very important. When we had out latest printer installed they told how long to clean the parts. They said do not go longer than that or it will cause problems. The IFU recommendations are not a suggestion you have to follow them to a T. They know what's best for their material and have spent a lot of time developing the process. Don't bastardize it like we all like to do with everything else we get our hands on.