Iâve had my Form1+ for almost 5 months now. Iâve made dozens of prints using FL Flexible, Clear, Grey and MJ SF Resin, with only a few print failures (all do to my mistakes in positioning the model or trying to reduce the support density and point size too much). I have NEVER cleaned ANYTHING inside the printer. Once, I think I noticed a spec of dust on the mirror and I gently blew it off the mirror with my breath. Besides that, nothing.
The room I keep the printer in is also where my computers are, and this is also where I regularly smoke cigars (the room has about 300CFM of exhaust fans, but it still gets a bit smokey). Now, I did make a dust cover for my printer, and itâs covered whenever itâs not in use and in use or not, if Iâm smoking a cigar. And I do used compressed air to blow-off the external surfaces before I change a Tank. But thatâs it. I keep expecting the âother shoe to dropâ but the printer continues to work pretty much flawlessly.
I read these postings about cleaning the mirrors and have to wonder if youâre doing more harm than good. The primary mirror is actually mirrored on the reflective side, not on the back side of the glass panel. Thereâs a very fine coating of Aluminum, and Aluminum is very soft. I donât care what you swab it with, Pec Pads or other, you are definitely going to abrade the surface by wiping it with anything. The more you do it, the worse itâs going to get. The laser beam is easily distorted/diffracted and scattered by scratches, and your print quality will have to suffer as a result. The more you clean the mirrors, the more scratched theyâll get (even if you canât see it). The more scratched they get, the less operating margin you have, which means you end up having to clean the mirrors more often as the optical path between the laser and resin tank degrades and so becomes more sensitive to contaminants on the mirrors.
There are only a few sources of contaminant, moving parts inside the machine, the ambient environment, and the resin tray insert/removal operation. The stepper and galvo motors, their bearings and ball screw and hinges are going to generate small amounts of fine aerosol lubricant and small metallic particles. Aerosols might cloud the mirrors over time, but probably not for a pretty long time unless thereâs something wrong with a Bearing or thereâs way too much oil/grease. Any metallic particulate will fall to the bottom of the machine, it wonât float around. Ambient environment is probably the next biggest culprit for particulate. The machine isnât particularly well sealed and I suspect opening and closing the cover generates some âpumpingâ action with the area in the lower enclosure. I tend to blow the machine off before I open the cover, if the machineâs been sitting with my home-made dust jacket removed for a while.
I think the worst source of particulate getting on the mirror is likely to be the resin tank. Aluminum mounting rails with a near-interference fit with the Acrylic resin tank, where the thank has to be slid along the rail a distance of nearly 6" during tank insertion and removal. That is unquestionably generating a lot of particulate (I used to make HDDs, I know a lot about particulate) and since the tank insert/removal operation takes place directly over the mirror, the particulate is going to end up on the mirror. After you remove a tank, before installing another, itâs worth wiping down the tank mounting rails with a damp cloth (without dripping water in to the machine), particularly if you see any white residue on the surface of the aluminum. That white powder is ground-up Acrylic dust thatâs going to end up on the mirror if you donât do something about it (IMO, this is probably the most disappointing component of the machineâs design. Friction fits generate tons of particulate and particulate is really bad for anything that uses laser optics and depends on a clean beam path. FormLabs ought to have looked for a better, less âfrictionyâ mechanical mounting scheme).
But bottom line, if your mirror is dirty and is requiring you to clean it off regularly, I think that means youâre doing something else wrong. You should look to identify and eliminate the source of the contaminants that get on the mirror, vs. a regimen that involves cleaning the mirrors regularly⊠IMO, YMMV.