Here are a couple of shots of a test I ran earlier today:
The piece is about 3.5 inches in diameter. The laser is a 2.5w (2500 mw). The feedrate was 40 IPM. Cutting time was 17 minutes.
The first pic is of some Dover clipart that I auto traced. The second is some vector clipart.
There is a bit of a process to doing this. It is NOT a good idea to run a finish pass and then start laser engraving. The results are much better if the piece is sanded after the finish pass. In this case I sanded to 400 grit. Pretty easy to do. One way is to just enter a manual command to do about 50K rotations and then the piece can be sanded on the rotary axis. I prefer to just move the chuck and all onto my lathe and do it there. After engraving, a light sanding is required to remove the smudging and make it crisp.
BTW, I discovered my dust collector works great for removing the smoke. Who'd a thunk? It is a Jet 1100 with a pleated cartridge. Evidently that cartridge with all the fine dust caked up inside removes smoke. I could not smell or see any in the shop after cutting. But it was fun watching it get sucked up.
Soooo, this laser thing is working out very well!
Edit: The dark spots on the lettering are not caused by the beam turning on, it is just that the little loops are close together and it looks like a black blob in the pic. Also, I did not sand the lettering very much after engraving. :::::sigh::::
Low Profile CNC Router Vise