80w vs 100w Thunder Laser for Engraving

[Chris T Carpenter]

I'm looking at purchasing a Thunder Laser Nova 35. I primarily engrave on 1/4" clear acrylic. Would a 100w make a difference in engraving quality vs an 80w? I asked Thunder Laser for the difference in dot size and they said they didn't have it.

[Kev Williams]

If you're primarily engraving, you don't want more than 80 watts, as DC lasers have a minimum power % at which they'll fire consistently, around 6 to 8% power setting. I engrave most Rowmark plastics with my 80w machine at around 12-14% power at 500mm/sec. A 100w machine might be hard pressed to find a 'delicate' enough power setting.

Your beam spot difference will be negligible IMO, best advice I have for a smaller beam spot would be to try a 1-1/2" focus lens. You'll have a bit smaller spot and a bit more power density, which would accentuate the problem with a 100w machine.

[Chris T Carpenter]

Thank you. I think I'll get the 80w.

[Rich Harman]

Dot size depends upon the incoming beam size and focal length. Counterintuitively, a larger incoming beam results in a smaller spot. 80W is typically the largest DC tube that is recommended if you are going to be doing a lot of engraving, and it still cuts 1/4" acrylic well.