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+--- Thread: Ok, what went wrong? (/thread-2698.html)
Ok, what went wrong? - Vinny - 06-01-2015
Now this is one butt ugly cut. The pic actually makes it look better. So what did I do wrong? Plasma cut (pilot arc 50A), about 70 PSI. While cutting it was trying to weld itself back together. Consumables (and cutter) are new, but to plasma cutting, so am I. Not following the line was all me, I should've used a straight edge cuze the line got hard to see. The steel is 4x4 5/16" thick.
![[Image: butt-ugly-cut.jpg]](http://metalshop.nobucks.net/pix/butt-ugly-cut.jpg)
RE: Ok, what went wrong? - dallen - 06-01-2015
could be from slag buildup in the tube at the area of the cut. or one too many Linenkugals
I've seen worse but it was in 2 inch plate
DA
RE: Ok, what went wrong? - Vinny - 06-01-2015
Yeah when I went out to start putting stuff away I hit it with the pliers and the dross came off, but while cutting I was getting alot of blowback and like I said it was trying to weld itself together. Not enough air pressure?
RE: Ok, what went wrong? - dallen - 06-01-2015
could be whats the recommended pressure for you plasma?
DA
RE: Ok, what went wrong? - Vinny - 06-01-2015
45 - 72 PSI.
RE: Ok, what went wrong? - dallen - 06-01-2015
hard to say what caused it, could be one of a handful of different causes,
RE: Ok, what went wrong? - f350ca - 06-01-2015
Your just getting shaky in your old age Vinny. A straight edge is the only way I can get a decent cut. Plasma is totally unforgiving when it comes to advance speed and side movement. Too slow moving is better than unsteady fast. 5/16 might be pushing the envelope for the torch too, my Hypertherm is rated for something like 3/4 cut and 1 inch sever, but 1/2 is pushing it, even 3/8 isn't nearly as nice a cut as 1/4.
RE: Ok, what went wrong? - PixMan - 06-01-2015
Wish I could help but I know a lot more about rocket surgery and brain science than I do plasma cutting or welding.
We can agree, however, that your cut is indeed buttugly.
Try lowering the air pressure to get into the lower to middle of that recommended range and see what difference it makes? If that doesn't work, switch from Leinenkugel to Sam Adams or Yuengling?
RE: Ok, what went wrong? - EdK - 06-01-2015
You must have gone to the Ed school of welding and plasma cutting.
Ed
RE: Ok, what went wrong? - Vinny - 06-01-2015
How did you know, Ed?