Calling all cutting torch experts

OK, I need help before I pull whats left of my hair out. Harris torch
running a #000 tip for 1/8" steel, acet at 5 pounds and oxygen at 20
pounds. When I start the cut I preheat until the parent metal begins
melting and then press the cut bar, and here we go. As I move across
the parent material, a hole naturally forms where the oxugen is
blowing the molten metal away, but once I pass that point, the slag
re-joins behind the flame and closes the gap! I never have the piece
just fall off with the first pass, I have to go back and melt off
enough slag to make fishing weights. What the hell am I doing
I've tried a gentle flame, I've tried a roaring inferno, nothing seems
to give a nice clean cut.
Reply to
Ronnie Lyons, Meridian, Idaho
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Go faster. Tilt the torch more. Are your regulators working properly? You can try turning down the acetylene to 3# too. 1/8" steel isn't real easy to burn. If you're cutting straight lines, you might consider one of those new blades in a wormdrive saw. I don't remember exactly about the new blades, but if you google on this group and "Tenryu" you'll dig it right out.
R> OK, I need help before I pull whats left of my hair out. Harris torch
Reply to
Grant Erwin
Your tip may need cleaning. Light your torch and adjust the flame. Now pull the cut bar and look for a tunnel down the middle of the flame extending out a few inches. The flame should make a spitting sound at this point, if it isn't, clean your tip.
Reply to
"Ronnie Lyons, Meridian, Idaho" wrote: .(clip) When I start the cut I preheat until the parent metal begins
wrong...Ernie...anybody...? (clip) ^^^^^^^^^^^^^ I an not Ernie, and not even an expert, but I'll offer what little I know. First, I don't think this is the source of your problem, but you don't have to take the steel all the way to melting temperature to start your cut. A red heat should be enough--gently open the cutting oxygen valve, so as not to cool the metal, and the cut should start. From that point on, most of the heat to sustain the cut comes from the burning action by the oxygen stream.
As to the "rewelding" behind the cut, I had that trouble when I was learning, when I tried to deal with thin steel. This was the solution. Tilt the torch over, so the oxygen is directed toward the uncut metal. That way, the torch thinks it is cutting thicker material. Also, the force of the oxygen jet blows the molten metal away from the already hot edges of the completed cut, so you will have less tendency for it to wet across the completed cut.
And, the other piece of advice I remember from my tutor is: "Go like hell."
Reply to
Leo Lichtman
I suspect you are cutting straight down into the metal. Try leading (aiming the torch - about 30 degrees) into the direction of cut.) . Regards. Ken (probably talking into my hat)
Reply to
Ken Davey
Thanks for all the great tips, I'll try them. You are right in that I'm holding the torch straight up and not slanted in the direction of the cut.
Reply to
Ronnie Lyons, Meridian, Idaho
I went brazosport college in 1980-83 for welding. it sounds like you need to adlust your gases to 5 and 40. these are standard settings.
Reply to
A couple of things you may try.... One is to lean the torch back a little ways like you were trying to "undercut" ahead of the kerf. Secondly, I would cut back a little on the oxy pressure. It's remarkable how thick 10psi will cut - especially when you shoot that 10 psi out through that tiny hole in the tip. Thirdly, get the tip of the torch down CLOSE to the metal, just so the little neutral tips coming out of the preheat holes are touching the metal. Holding the tip higher lets you heat up too much metal on the sides of the kerf. And lastly, move fast enough that you are just barely able to preheat the metal enough to cut. Lallygag around and you have a molten puddle to blow through, which will flow back together after you pass the area. Hope this helps. Ken.
Reply to
Ken Sterling

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