I have found that cleaning the main mirror with IPA greatly increases my print success. After about 2 months of use (20-30 prints) my success rate was down to 10%. After cleaning the main mirror with PEC-PADs and IPA according to FormLabs’ directions I’m back to ~ 100%. Dusting didn’t hack it. I have been through this cycle twice. My worry is that cleaning the main mirror every 2 months will kill it.
From my experience, I think a good recommendation would be to use a squeeze-duster before every print and IPA once a month. I always used the lightest pressure that would press the pec-pad to the mirror, and I didn’t feel it was doing any harm. I know others have reported issues though. I’m not sure if they were using a delicate touch or not.
Thanks for the reply. In my experience the dust on the main mirror may cause small imperfections in the surface of the prints but any haze on the main mirror will cause print fails where half of the print peels off. Its hard to see the haze unless you light the main mirror from the inside of the printer with a small LED light.
Yea the LED light is a must. After I started dusting the mirror before every print there was always at least one particle that was not there when the print started. And yea, the haze builds over time, I believe it is resin fumes.
Something to keep in mind (when using an LED light).
Powerful LED flashlights (200 lumens and above), especially with TIR optics, actually tend to emit quite a bit of near-UV and UV light. Be careful when you use them near your resin.
I actually use a flashlight (about 500-600 lumens) to glue cracked or broken prints with resin.
I sometimes use it to cure a print that came out underexposed too.
If you bring it up too close, it emits enough light to cause the resin to cure so quickly it starts smoking.