Cutting with O/A...

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I've been lurking this website for a long time, and I'm new to oxy/act cutting and welding.Today I was trying to cut some 1/8" and 1/4" steel for practice.  I was trying different pressures and techniques.  The cuts seemed to be going well, but the steel would flow back around the tip and reform.  I had to go back and recut.  It made for a very sloppy job with too much slag.I have the Victor Performer with the stock cutting attachment and tip. I ended up with the oxygen at 25 pounds, and the acetylene at 7.  I watched several You Tube videos that pertained cutting with O/A.Thanks for any suggestions. I ended up
Reply:Sounds like you either have too large of a tip in or are moving too slow, or a combination of both.  In addition, there's no need to have your acetylene pressure at 7 for that thin of steel.  Something around 4 would be better, and personally I'd have the oxygen higher, like 35.
Reply:X2 on more oxygen... Perhaps you didn't have enough pressure to "blow" the steel out of there...Heres my youtube video...[Account Abandoned 8/8/16 Please Do Not Attempt Contact Or Expect A Reply]. See you on YouTube! -ChuckE2009
Reply:First make sure the cutting hole in the tip is clean w/ your tip cleaner. Best way I've found to cut 1/8" is lean the tip back from direction of travel and go as fast as you can and still cut. If it starts cutting bad, stop and clean the tip again. When the tip is in good condition and clean, when you open the cutting valve it should "pull" the dull blue part of the flame out to at least twice it's length.                                       MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:If you haven't read the instructions, do so.  They usually have a chart that has recommended pressure setting for each cutting tip. I believe you should be using a 00 for 1/4" plate and 000 for 1/8" plate. Each tip is designed to have a certain cutting range at certain pressures and trying to use them out side of there setting makes them more difficult to use. Yes you can cheat and get tips to work outside there range but it is best to learn to use the torch properly because at my last job you could swear Victor only made a #2 cutting tip, no fun to use on everthing.
Reply:OK, thanks for the input.  Lanse, I watched your video this morning, thanks.Mla; When you say, "lean the tip back", do you mean to lean cutting head so that the tip points slightly back towards the cut line?  I think that's what you mean.  I'll clean out the tip, try more oxy, see if that helps.  Thanks!
Reply:Yes.  If you see your sparks traveling straight down from the cut, you're traveling too slow.  They should come out at an angle, and you can tip your torch slightly to follow that angle.
Reply:Yeah, I meant lean the head over 20 to 25 deg. away from your line of travel.                                                  MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:Originally Posted by WenValleyMla; When you say, "lean the tip back", do you mean to lean cutting head so that the tip points slightly back towards the cut line?
Reply:Originally Posted by Pro-Fab. . . On thinner metal, angle the tip forward in the direction of travel. . . .
Reply:The preheat flames should not change size or shape when you hit the oxygen jet lever. They need to stay neutral. No endorsement of the following as I have not read the article, but it has promise. http://www.popsci.com/diy/article/20...-cutting?page=City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:if you keep the ox/fuel ratio about 5:1 or 6:1 you wont go wrong..look on the tinmantech site for a description of how toset up a torch.. always point the tip in the direction of travel as the heating ahead of you is critcal to getting a good cut..if you drag/pull  towards you youi wont have to move your glove across the part you just heated and cut..also pushing makes it harder for me to angle the tip as described...
Reply:Lanse,I watched 1/2 of your you tube so far, I'll watch the rest tonight. One thing I noticed is you seem pretty focused on safety yet you didn't purge the lines at startup?Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:There's nothing like a proper tip chart to give correct tip size, pressure settings, gas flow rates (so you don't try to draw more acetylene than your cylinder can safely give) and speed ratings.It sounds to me like the OP was flowing too much gas, maybe using too large a tip, and moving too slowly. To cut 1/8" cleanly with a gas torch is not easy. You need to learn to tilt the torch back away from the cutting line to make the steel effectively thicker.
Reply:Thanks to all that responded.  I appreciate your help.  I stopped by a buddy's shop today, he's my welding Yoda.  He showed my how he sets up his torch.  I came home and duplicated his setup and was back on track.  What a difference.  I cut down on the fuel, and stepped up the oxygen, and readjusted for a nuetral flame with cutting lever both off and on.
Reply:Originally Posted by WenValleyThanks to all that responded.  I appreciate your help.  I stopped by a buddy's shop today, he's my welding Yoda.  He showed my how he sets up his torch.  I came home and duplicated his setup and was back on track.  What a difference.  I cut down on the fuel, and stepped up the oxygen, and readjusted for a nuetral flame with cutting lever both off and on.
Reply:It doesn't hurt to read the instruction manual also.
Reply:I have found that if I keep the tip too close to the steel it tends to cause the kerf to seal back up.  The problem is that the preheat jets are melting the steel and not allowing it to freeze quickly enough.  Try keeping the tip 1/4" or more from the surface.  The further away from the material you are the longer the preheat takes to get it started.It helps to remember exactly what is happening with the OA cutting torch.  Once you start the cut the oxygen jet is causing the steel to literally burn - this is what does the cutting.  The preheat jets don't do much once the cut is underway.  With this in mind you should see that once you have started the cut you can lift the tip up a bit and the O2 jet will still do its job just fine.Watch your rate of travel - you should move as quickly as you can without loosing the cut - this gets the heat off the fresh cut and lets it freeze before it flows too far.Hobart LX235Victor 250 Oxy-Acetylene Rig (welding and cutting)Bobcat 773F-350, 1999, 4x4, 16' 10K# trailerOutdoor Wood Burner - 10 cords/year