Excuse me for leading away from the question, but suggest you not pass by the idea of waterjet cutting for material like that. No dross to worry about at the edges.
We currently cut some aluminum on our Mitsubishi 2,000 watt laser but we get pretty excessive burrs and it seems to put a lot of wear on the lenses and mirrors as it is much more reflective than steel. We usually will use our laser for development of a few parts then after the precise blank is developed we will send it down the street where they have a 4,000 watt Mitsubishi laser that cuts aluminum just as clean as steel. For us, with our current vendor base, I find that the laser is cheaper to cut aluminum until you get up to 5/16" thick. Over 5/16" I highly recommend waterjet but for 3mm I would seek out a 4,000 watt laser. It will cut much faster than waterjet with less consumables, (grit, nozzles, etc.) NTC and Mitsubishi have good reputations for cutting aluminum. I hear the Trumpf's are good until the resonator goes and then you have to replace the whole resonator as other brands are rebuilt for much less money.
If you would like any more information, please feel free to call me to discuss:
Thank you,
Marcus 586-839-7979
marcus@asapstamping.com
www.asapstamping.com
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