Notice - Stop using compressed air on mirrors

Here’s a post I made an hour ago or so in the middle of a larger post but thought afterward I should make it more visible. It explains what others have been seeing too, but I didn’t figure out the cause until it happened to me…

Well I just screwed up. My mirror was a little dusty and my wife had a can of compressed air sitting next to the printer. I figured a little puff wouldn’t hurt. BAD IDEA. All of the compressed air you buy these contains a bitterant to prevent abuse, but I figured no big deal. But there is A LOT in there! It spit all over my mirror! My mirror is WAY WORSE. I have requested the secret pec-pad instructions from FormLabs and am waiting…

Edit: This picture is not my mirror, it is from @Frank_Guthrie.

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Yikes, Josh. That’s too bad. Thankfully, I think you should be able to bring that mirror up — but that’s a good warning on compressed air. The mirrors can be very delicate!

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@Sam_Jacoby, I should mention that picture is not my mirror, it is from the other post (@Frank_Guthrie) that I mentioned and better shows the orange tint to a greater degree than mine would. I didn’t feel like photographing mine. It’s a difficult picture to take and I didn’t want my tank removed any longer than necessary so the mirror would not get worse. I had a print to do.

Thank you Josh. If I remember right formlabs suggests to bend the straw of the can so no liquid gas can reach the mirror.
Atm I am waiting for my repaired printer and since this compressed air out of a can method won’t work I need a new solution for cleaning! So what can be suggested instead? Getting a big compressor to get sure?

Great question Marcus, I learned about this from @Frank_Guthrie as an alternative:

I bought one.

I already got a Blaster like this and its too weak in my opinion.

If you try a large compressor be sure to install an air dryer to remove the moisture it will squeeze (condense) out of the air. Personally I am kind of scared of blowing air around inside the printer because it stirs up the other dust that has settled. Remember, everything inside the printer is as dirty as the mirror, you just don’t pay attention to it. Stirring up a cloud of micro dust and dust could easily blow against a galvo mirror and give you bigger problems.

you are right Josh, this might not be the solution. I hope formlabs can come up with a concrete solution soon.

an other solution could be: use at same time an air compressor (with air dryer) at low pressure + a vaacum cleaner. Place the compressor nozzle and the vaacumcleaner’s tube inside the printer, both adjusted on low power.
By this way you can have a nice air circulation and flow that will move the dust and suck it at same time.
With low air pressures and powers you will remove lot of flying dust, saving the delicated components of the machine.


Try this:

I spoke directly with the manufacturer (Stoner) and confirmed by phone that this product does NOT contain bitterant (ph # 717-786-0804). It’s about $12 for a 12 oz a can shipped via Amazon depending on the source. The manufacturer sells a case of 12 for about $57 with free shipping, FYI.

I ordered a can from Amazon just to try out before committing.


That would be cool, I didn’t know it was still legal to sell it that way but I must be wrong. Let us know if it makes an orange haze.