Here are some steps for aligning the laser and cleaning the lens, courtesy of DavR:
1. Get a flat piece of material on the laser bed, and the laser head positioned over the left most bit, and allllmost touching it but not quite
2. On the laser go into the menu / jog setting / 1.0mm
3. Fire a test laser dot, then jog right 2mm and lower z table 1 mm
4. Repeat 3 ten to twenty times, until it is obvious the burn spot is getting bigger
5. See which dot is most in focus -- it will be the smallest (and possibly darkest / deepest cut)
6. Count how many times you need to raise the z table to get back to that setting
7. Fire another test dot, confirm it looks like a nice small in focus dot
Resource: Instructable about mirror alignment
Cleaning Lens: (do with laser cutter powered off)
1. Be very careful, dont want to scratch the lens. Not super expensive, but will probably take time to get a replacement
2. unscrew the bottom of the lens head somewhere
3. pay careful attention to the orientation of the lens in the tube, you need to put it back the same way up next time (the front & back of lens are not symmetrical)
4. gently wipe any debris off the lens with a microfiber cloth or whatever
5. then use a little more force to clean it with a microfiber cloth and rubbing alcohol to get and smoke that's adhered to the lens
6. put everything back the way it was
Cleaning the Chiller Filters (The filters must be cleaned every 15-30 days)
1. Make sure the (2) filters on the chiller are clean or the laser may overheat.
2. Turn-off and unplug the chiller before the next steps.
3. They are located on each side of the chiller towards the front, if they look like cotton you are seeing dust build-up not the filter itself.
4. Remove the (4) screws and clean the filters on both sides.
5. There is another screw at the bottom of the filter that holds it to the face plate.
6. Re-assemble everything as it was.
7. Plug the chiller back in and turn it on!