1/4" plate & OA

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I'll be cutting some 12x12 squares tomorrow out of a piece of 1/4" plate I found at the scrap yard. I have done some OA cutting but not really a lot. I have trouble maintaining my distance and keeping the cut going. I am going to try out my guide wheel attachment tomorrow, to maintain the distance, and a straightedge for a guide. I'll be using my Victor 100 series cutting attachment. According to my tip chart I should use a 00 tip? And 20-25 psig Oxy with a flow rate of 35 cu ft/hr? Acetylene @5 with a flow rate of 6?Any tips (no pun intended) would be appreciated, I really want to learn to make some nice cuts like I see at the scrap yard whenever I go there.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:I suggest practicing by hand without a guide. Mark your desired cut with soapstone or chalk.Practice without the torch running. Make about six-inch straight "pulls" (I'm right-handed so I go right to left)and note the max distance you can make a controlled straight cut.When you stop in mid-cut, if your restart on the SCRAP you avoid having a blowhole. It's repetitive motion. Practice until it's natural. PREHEAT helps. You can make a preheat pass then make the cutting pass and note the difference.
Reply:Thanks, I tried that. Then I tried some practice cuts. Should I be angling my tip a bit away from the direction of travel?My practice cuts don't look [I]terrible[I] but they don't look as nice as I'd like. There will be several inches that look real nice then a section that will have a lot of slag. It is tempting to go up a size on the tip, it almost seems like the oxy stream is not strong enough although it is a new tip and I am set at 35psi. I have to just creep along or I lose the cut.I was angling the tip slightly away from the cut direction.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:That should be enough  tip and o2 pressure for 1/4". You said scrap. If it has a layer of rust grind that of first it makes it hard to get even heat. I like to use a straight edge usually a angle iron. I like to tip into the direction I am cutting.Millermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:Well I didn't know that about the rust, it does have a layer of rust on it. I'll try cleaning it up on the next one. And angling my tip into the cut.ThanksMiller 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:You could try next size bigger tip for faster travel dont have a chart in front of me. I usually run 0 or size 1 but I cut more 3/8 and 1/2 than 1/4. Should be able to find a chart with travel speed for your set up to get in ball parkMillermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:You'll get your best cut quality with the tip square to the plate. Too much O2 pressure can reduce cut quality as well. I never cared much for a straight edge, as I always felt like it was dragging on the tip. Preheat flames should be close to the plate, but not touching. I was tought that you light your flame with just acet., open the valve til the flame leaves the tip, then back down til the flame touches the tip again, then add O2 to make a neutral flame.
Reply:I use a piece of angle iron for a straight edge.  I find a piece with a long enough leg I can rest the tip nut on it.  Keeps the standoff even.  Lay the angle iron so that one leg points straight up.My name's not Jim....
Reply:OK Guys heres some pics, critique awayMiller 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:What setting and tip size did you go with?
Reply:gas=5 oxy=30 tip=00Miller 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:The victor tip chart states 20-25 for a 00 tip. If you put to much O2 it will cool off the slag and it will stick like in your pics. Can 30 psi work for you , yes but follow what the tip chart states and practice and you'll be able to get some nice looking cuts.