Kirk,
The laser engraver is very basically like a dot matrix printer, but instead of ink you have a laser beam. The beam comes from the back of the machine, hits 2 45 degree mirrors, then down through a focusing lense. The lense travels back and forth and the laser beam comes out at the appropriate times to vaporize the material. I also have a rotary attachment that holds the pen and rotates it in unison with the lense movement. It's an incredible machine that with the 2" lense will cut a .005" line. I didn't time the burn on the pen, but it must have been less than 3 minutes. My favorite part of all this is easy art work. It works off the printer port on the computer and will print anything that is on the screen. You don't need "lines" like a computer numerical controlled router, all it needs is a picture. It will see shades of gray and different colors to change intensity of the laser beam to change the depth of cut. You can almost get a 3d look. The bad news, MONEY! My machine is 25 watt laser (small "horsepower", lasers here at Caterpillar are up to 3,500 watts to cut thick steel) and it was a rebuilt 7 year old machine. $9,000 with the rotary attachment. I bought it from ACCESS Lasers in Hudson WI. Very nice people. I had a portable bandsaw mill and sold it when I had too much lumber. As I explained it to SWMBO, I have to reinvest that in machinery so we don't pay so much Federal Income Tax. I think it worked?
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