Let’s say I have a thicker piece of wood that I’d like to cut and want the accuracy of the laser rather than using my bandsaw. Would it be possible to just run multiple passes across the material to cut deeper and deeper each pass until I’ve punched through? Wouldn’t this just be a matter of readjusting the focus of the laser on each pass?
Maybe. But the focus only has a 1/2" range. 1/4" is fine for wood. 1/2" by flipping it, assuming they get all the registration S/W to work correctly. MAYBE deeper than 1/4" with multiple cuts but the beam has an slight hourglass shape with the focus in the middle. Widens the kerf with each pass, chars the edges, extremely slow process, etc. Don’t think it realistic to cut anything deeper than 1/2" with any method.
No this does not work.
While it is true that you can perform a second pass or even a third pass to get through the material should it not cut correctly there is a limit to how thick you can ultimately cut.
The laser comes out the final lens in an hour glass shape, the surface of the material should be in the middle of the hour glass to start the cut. If you refocus the cut, some of the laser light will be blocked by the walls of the first cut. Eventually, if you go deep enough, not enough light will make it down the gap to actually cut the material.
When you think about it, it’s the same reason you can’t cut thicker material in multiple passes with the focal point in the same position.