Not sure if you resolved your issue. I will chime in for future researchers. For 14 gauge, 160ipm seems to be on the fast side. What I have learned is to read the sparks. By that, I mean the sparks when cutting. If you get large rooster tails, and a lot of sparks above the material, you are running too fast. At the proper air pressure and speed, the right amount of material will be removed and the sparks will be more underneath. Also, did you check the condition of your swirl ring?
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