New to lasers, Need help, how to clean cut 1/8" mild steel on a 2200 watt laser

[ezdiecutting]

We have recently purchased a 2200 watt cnc laser, we are in the steel rule diemaking business, we make dies that cut carboard, paper, gaskets, plastics and so on, we use the laser to burn plywood for our dies and then we bend cutting rules with sharp edges, blades and exc, which we drive into the slots the laser burns for us for whatever we are making, box dies, gasket dies,and so forth. Now every so often we need to cut mild steel for backer plates, this where i need help, we have not been able to get a clean cut/edge on the back mostly, we turn on the assist oxygen, we try speed, psi, and we set the laser about 1200 watts, the watts is the only thing we have not changed. Anyone have some answers. We are trying to cut 1/8 mild steel.

Thank you

Bob