Why does the cut fill with slag and close in behind me??

When I am cutting metal with my acetylene torch, the cut usually fills back in behind me and I have to tap out the peice I am cutting. I have seen people make cuts that were very clean and neat, I know I am doing something wrong but I just dont know what? any tips on basic cutting torch procedures?? Thanx

Everybody’s right.
Anything from wrong tip, to speed , distance ,angle etc.
If you are sure you have the right tip for the thickness of metal.
might try upping the oxy pressure a little.
You should have a strong flame w/ no smoke & when you hit the cutting lever a bright flame with a bit of a roar is a good indicator.
The extra pressure will blow the molten metal out of the cut & give you a shower of straw colored sparks without pooling.
You will know its right when there a clean underside on the workpiece ( no dribbles) & very small & few molten globs on the floor.
Your gas supplier should have tables for tips & pressures.
Fun aint it?

oxy fuel cutting

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