Cuttin' 1/8" sheet metal with a O/A torch?

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I have problem cutting 1/8" sheet metal with my torch. 1/2" is no problem at all and 1/4" also works fine.My primary problem is that the metal wants to melt together again while cutting. After I'm done I can break it off but there is also lots of slag. So I can cut it but it looks like crap.What should I be looking at changing? I'm using the smallest cutting tip for my torch suitable for 1/8-1/4" according to the manufacturer. I've read the "How to use your torch" sticky thread and watched all the videos.I want to cut out a sign in 1/8" sheet metal but if I can't get a decent cut there is no point in doing it.So first of all I wonder if it is possible to do and if anyone have any pictures 1/8" material cut with a O/A torch so I know what to aim for? I also wonder if it is possible to cut thinner than that, for instance 16 gauge.Any other tips or tricks would be much appreciated as well. Or links to videos or other info.
Reply:I found out right now that there is actually an even smaller tip for my torch that is made for cutting 20 gauge up to 1/8".Would it be better to use a tip rated on the small side rather than on the large side, if you know what i mean?Last edited by Pete.S.; 04-25-2013 at 05:17 PM.
Reply:I lay my torch down at a 75 degree angle and go fast, cuts nice once you get the hang of it.Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:X2 on what Tozzi said www.georgesplasmacuttershop.comPlasma Cutter and Welder Sales and Repairs--Ebay storeTec.Mo. Dealer Consumables for the PT and IPT torch's
Reply:Originally Posted by TozziWeldingI lay my torch down at a 75 degree angle and go fast, cuts nice once you get the hang of it.
Reply:For straight cut what Tozzi said? But for letters and such I just a smaller tip, a cooler preheat, faster cutting speed and possibly a little more stand off.  Thin metal is trickier than the thicker
Reply:Harbor freight Plasma cutter.......  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Pete. S.Victor makes a sheet metal tip in several sizes.  It has one preheat orifice and a foot for contact. Search Google Images  -  Victor 2-3-110.Opus
Reply:What Tozzi and Mechanic said, angle into the cut, and me I almost drag the tip and move fast, and it most likeley still warp. Pain in the buttocks I hate being bi-polar it's awsomeMy Heroes Have Always Been Cowboys
Reply:if you run too much pressure on your oxygen regulator you will get similar results, for 1/8" plate I have best luck with 15-20lbs of oxygen and a 00 tip
Reply:I do a lot of cutting on thinner stuff and use a 3/0 tip. You need to keep the plate right at the blue flame, very close. Your travel speed must also be very fast. If you don't occasionally lose your cut then you are probably going to slow. For straight cuts you can drag the torch tip on the metal with the torch cocked at an angle. Here's you some pictures. Most of these were cut out of 14 ga. but a couple were out of 1/8", nothing thicker. Attached Images
Reply:Bob very impressive work!!
Reply:What pressures are you running with the small stuff?I've found that when I don't follow the recommended settings I'm usually running the torch too hot.  I tend to get lazy and set it the same every time and forget to re-adjust for thinner stuff.Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:1/8 and less is where a plasma really shinesBacked my CATMA over your CARMA oops clusmy me  What would SATAN do ?? Miller Trailblazer 302 AirPakMiller Digital Elite  Optrel Welding HatArcair K4000Suitcase 12RC / 12 VSHypertherm PM-45Rage 3 sawRusty old Truck
Reply:Holy cow Bob are you cutting that stuff out FREEHAND? NICE WORK!
Reply:Aight, so I bought the smallest tip available today and made some more cutting. No luck on that though even when I tried different pressures, different travel speed, different distance tip to work, angling the torch etc.Maybe my pressure gauges are screwed up because I can't adjust my torch to a proper flame when I look in the tables and set the recommended pressures.Anyway, I made some more tries and actually had more luck going to a larger than recommended tip and running it on lower pressure.Below are some images of the best I was able to get and the tip I used. This is just from the cut, no removing of slag or anything. 1/8" sheet metal. The cut is not straight but I was not concentrating on that. Comments are welcome on how to make it better!  Attached ImagesLast edited by Pete.S.; 04-26-2013 at 04:53 PM.
Reply:PS. On the tip I used, the hole for the cutting oxygen is 0.039".The new tip I bought had a 0.020" hole. I also tried the size between those two.I'm not sure how these sizes are related to US sizes. Here the tips are just called 1,2,3 etc.Last edited by Pete.S.; 04-26-2013 at 04:59 PM.
Reply:Can't say it will make any difference, other than to reduce a variable, but here's something you might consider. You see the hexagonal array of preheat holes in the tip? Install the tip so you don't get preheat on either side of the leading edge of the cut but directly in front of it, i.e. orient the tip so the longest distance between holes is along the travel direction, in essence minimizing the preheat "width". If that makes any senseXMT304 (school)SP125+ (home)HF 4x6 BandsawGood judgement comes from experience and much of that comes from bad judgement.
Reply:Originally Posted by wireheadCan't say it will make any difference, other than to reduce a variable, but here's something you might consider. You see the hexagonal array of preheat holes in the tip? Install the tip so you don't get preheat on either side of the leading edge of the cut but directly in front of it, i.e. orient the tip so the longest distance between holes is along the travel direction, in essence minimizing the preheat "width". If that makes any sense
Reply:As far as pressures go, the chart is merely a guide line... don't worry about veering off. It can take some experimentation to find the right fuel and oxygen pressure for a given situation. I'd expect if you go back to the smaller tip and play with the pressures it'll work better for ya.Quite frankly the latest pics you just posted look about as good as you are going to get on 1/8" plate... If you need it better then that as others have said, you may want to consider a plasma cutter.The trick of introducing a large amount of torch angle to make the steel thickness the oxygen stream sees larger certainly works when a smaller tip is not available, but it really only works well in a straight line.Lincoln Idealarc 250Lincoln Weldanpower CC/CV engine driveLincoln LN-25 wire feederMiller Syncrowave 180 SDVarious oxy-fuel setups featuring Victor, Harris, and Prest-o-lite products
Reply:Originally Posted by Pete.S.I understand what you area saying. Do you think I have to much preheat going on?
Reply:Thanks for the replies so far. I'll read them more in detail later.I just wanted to post that I found chart on Victor tip sizes and the one I used cutting the 1/8" steel above is just a smidge smaller than tip size 0. Attached Images
Reply:You may be just going to slow. If you look at your last picture you will see that the cut looks different on the left half than on the right half. On the left half, you can see where you were just a tad too slow and the metal melted down onto the edge being cut. The right half is the correct speed as there is no melted metal on the edge.You might clamp a straight piece of metal to the metal you are cutting and drag the tip along it. Because there is not even any slight weeble to the tip, the cut should be almost machine perfect. That way you can test your tip and settings to see if it is the torch set up or you. Here is the only pictures of cutting small stuff with a guide on 11 ga., slightly thinner than 1/8". Attached Images
Reply:Originally Posted by Bob...some pictures...