Laser for a small cutter

[electrphile]

I'm building a small laser cutter (off an instructable) to cut SMD circuit board stencils. Most low-cost stencils for prototyping purposes are either mylar or transparency sheets. Now, I've seen people build cutters using 300mW lasers and my questions is will these be powerful enough to cut these materials. If I were to use a 1W laser instead what would I be able to cut with it and at what distance? Also I saw some great deals for 1W lasers in the 800nm range (which I think is non-visible spectrum). Would these be suitable for cutting?

 

[ccsnell]

I am just dipping my toes into the world of lasers but from what I understand, lasers outside of the visible spectrum aren't suggested as a starter because of the risks.

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