We use a Trump L 3030 laser to cut up to 5/8" A36 hot rolled steel. Our current cuts on 5/8" are good but our cuts on 1/2" A36 vary (incomplete cuts) from one side of the sheet to the other. The 5/8" material has more scale than the 1/2". The 1/2" almost has a cold rolled appearance. Niether have excessive oil on the surface. We use the standard tech tables. Could material chemistry affect the cut or could it be related to surface finish?