cutting straight long lines

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I have to cut a sheet of steel and i need to cut a long straight line. what should i use. thanks. it is a 6 to 1 oxy/ate torch. thanks
Reply:If I have to cut a long straight line in anything, I set up a good straightedge as a guide.Doesn't matter if it is with my oxy torch, my plasma, or my circular saw.I would grab a chunk of  scrap and attach the straightedge and make a test cut. This will tell you how far from the edge of the straightedge your torch will cut and how big the kerf is.My circular saw cuts 1 1/2" from the guide  to the near side blade edge set one way, 5" IIRC from the straightedge to the near edge of the cut from the other side. So if I want a cut 12 1/16" from the plate edge and use the 5" saw offset, I need to set the straight edge so that it is 7 1/16" from the plate edge. 12 1/16" -  5" offset = 7 1/16"Remember that you loose the kerf of the cut. That's why I usually set up a test piece and double check that I have the correct offset figured. Sometimes I have to set the straightedge on the "waste" piece rather than the  "Good" piece. Then I need to subtract the width of the kurf from my measurement. so if my kerf is 1/8" wide in the example above I would set the straightedge at 6 15/16" rather than the original 7 1/8" so that the piece is not too small by the width of the kerf. (been there, done that, and will do it again I am sure) That's why I always do a test cut.
Reply:ya, i'm just cutting a large triangle, probably 100lbs. I want to make it smaller , so it is not a heavy to move.
Reply:I use my Track Torch.  Yeh, I know smart a$$.I also have several lengths of 1 1/2" x 3/8" angle, 1 foot thru 4 foot, that I use as a straight edge to guide my hand held torch or plasma cutter for cutting straight lines when I'm too lazy to set up the track torch.Simply position the angle, spaced away from your mark the the distance from the cutting oxygen hole in the center of your tip to the outside of the tip.  Clamp the angle, and go for it.Good Luck
Reply:Originally Posted by paweldorI use my Track Torch.  Yeh, I know smart a$$.I also have several lengths of 1 1/2" x 3/8" angle, 1 foot thru 4 foot, that I use as a straight edge to guide my hand held torch or plasma cutter for cutting straight lines when I'm too lazy to set up the track torch.Simply position the angle, spaced away from your mark the the distance from the cutting oxygen hole in the center of your tip to the outside of the tip.  Clamp the angle, and go for it.Good Luck
Reply:Some one told me once, look where you are going, not where you are at.  It works for me freehand.  For really straight long lines, I grab a piece of angle and "ride" the torch on the angle.  When the angle heats up, it can warp on me causing a curved line.I also have some 1/2" X 3" plate with a handle welded to it.  I call it an Iron.  It makes a good guide and doesn't warp.Now I mostly use a plasma.  It has a 1" cup, so I add 1/2" to the measurement and use a guide.  It doesn't heat up and warp like with the torch.David Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Originally Posted by Fat BastardI still add a line that I want to cut so as to confirm that I am cutting in the correct place
Reply:Ok, this is gonna sound really weird, but I was exposed to lead paint as a baby so isss okFirst off, throw the soapstone in the garbage.  Get a good silver pencil and mark the line.Get as far back on your torch handle as you can.  You can cut straighter if the torch will move in a wide arc (I know it sounds weird).  See roughly where you can start and will have to stop on the wide arc.  Then get your left hand comfortable on the plate or a rest.  Two handed grip-left hand cradling your right hand which is holding the torchIf you don't believe me, try it without the torch running.  You'll be surprised how straight you can adhere to the line with very little movement where your hands are resting.  You'll have a few starts and stops.  I usually can cut around 12-14 inches at a time before a restart.  Kill the O2 at the point you have to restart, and lift the torch.  Don't do a long preheat before you start again.THEN GET ABSOLUTELY ZEN, AND BECOME THE LINE.  I don't care if a tick climbs in yer sock and starts makin a meal outta your left toe, or a small grass fire starts under the plate-- BECOME THE LINE.I have never been steady enough to cut straight without a rest, and using a straightedge hasn't been satisfactory.  Your tip angle has a tendancy to change, and the friction of the copper on the straightedge tends to drag and cause erratic cutting speed.You'll have to excuse me now, there's 4 very calm gents at the door with a nice clean white straightjacketYes, this is actually the way I cut"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by farmersammYou'll have to excuse me now, there's 4 very calm gents at the door with a nice clean white straightjacket
Reply:"Any day above ground is a good day"http://www.farmersamm.com/
Reply:For the time being, i think i will just use an old bed rail as my straight edge. I was also wondering, has any one herd of a thing called a cut stick or some thing close. It is a magnetic piece of metal that to lay where you want to cut and use it a a straight edge. Thanks
Reply:It depend on the work piece... if it aluminium... you either jet , laser or saw but for steel, if the work is not for aerospace, I would prefer torch...Here is a circular and straight cut with an old fashion but realiable oxy/acetylene torch Attached ImagesUnit in my fab shop dept:my good hand and team that trust me...A lone welder make art... a village full of welder make Miracles...
Reply:Originally Posted by mark123. . .it is a 6 to 1 oxy/ate torch. . . .
Reply:The guy standing is holding the hose for the automated turning, the guy at the back is holding and guiding the circular compass. Both the guy is standing on the plate which is wooden supported below. The floor will never be ruin. This is a cutting process not WELDING.This 3 person operated the old fashion cutting machine... anyway it feed their family then having see then sitting on the bench chewing their nail off...Unit in my fab shop dept:my good hand and team that trust me...A lone welder make art... a village full of welder make Miracles...
Reply:Originally Posted by MandauThe guy standing is holding the hose for the automated turning, the guy at the back is holding and guiding the circular compass. Both the guy is standing on the plate which is wooden supported below. The floor will never be ruin. This is a cutting process not WELDING.This 3 person operated the old fashion cutting machine... anyway it feed their family then having see then sitting on the bench chewing their nail off...
Reply:He is a student from the VOC school... he is slave labour until he learn to grind proper... we even loan him a shoe... he is send by the local school for a 2 month hand on experience... He see and learn until we say what he can touch...Unit in my fab shop dept:my good hand and team that trust me...A lone welder make art... a village full of welder make Miracles...
Reply:Originally Posted by MandauHe is a student from the VOC school... he is slave labour until he learn to grind proper...
Reply:Ok Uncle... did I mention I am going to polish the floor in next to year after the second building is ready?... But your advice is a great thinking ... I bet my worker will swear and love you to no end...I will tell this new marketing lady to move those plates thanks to you sir Attached ImagesLast edited by Mandau; 02-13-2009 at 11:32 PM.Unit in my fab shop dept:my good hand and team that trust me...A lone welder make art... a village full of welder make Miracles...
Reply:does anyone know what im talking about or will the nice men come for me with a new jacket to?
Reply:Originally Posted by mark123I have to cut a sheet of steel and i need to cut a long straight line. what should i use. thanks. it is a 6 to 1 oxy/ate torch. thanks
Reply:6 to 1 means 6 pre and 1 cut. I was talking about that cut bar or stick.
Reply:Originally Posted by mark1236 to 1 means 6 pre and 1 cut. I was talking about that cut bar or stick.
Reply:the cut bar or what ever from what someone told me a while back was that its is a megnetic bar that you stick to the metal as a straight edge.
Reply:http://www.lencocanada.com/pdf.d/800-05.pdf mark123 check out this link there is a variety of cutting and layout tools.Nothing Ever Got Done By Quitting, Never Give Up.
Reply:Originally Posted by mark123. . . 6 to 1 means 6 pre and 1 cut. . . .IT is the bar in that link. it will not paste. but it is in there. thanks for the help.Last edited by mark123; 02-14-2009 at 04:21 PM.
Reply:i can tell you that cutting will pop concrete and it hurts.  i ran a track torch cutting plates to size for our tanks.  the table was waist high and we would cut 3/8 on up with o/a and o/propane.  we used roofing tin to keep the concrete safe.  there was several pock marks when  we would forget to move the tin.
Reply:I hope those are welding glasses and not just sun glasses.Sunglasses will not protect your eyes.A trick for you.When you cut long lines or large curves leave a small part like 1/2 inch UNCUT every foot or so, then when you are finished you can go back and cut the  uncut small sections.Th purpose is you can prevent warping of the edge because the heat causes shrinkage.Very useful on curves and especially when cutting holes in a large sheet or portholes in a cabin of a boat.Last edited by Donald Branscom; 02-14-2009 at 05:48 PM.AWS certified welding inspectorAWS certified welder
Reply:get a piece of 2x2 angle iron and keep it in your shop.  whenever you need to make a straight line across a flat piece, measure, then clamp that angle iron to the piece on both ends, and just drag your torch alongside it.  Works fine for me."Real power is an arcair hand torch with a piece of 3/4 inch carbon and 1500 amps.  You feel like Zeus throwing a lightning bolt."
Reply:mandau i like both the torch guids  in yer fotos .. gonna see if i cant come up with something like the  straightcutter shown ..thanks
Reply:Originally Posted by denrepMark123 - What does  "6 to 1 oxy/ate torch" mean? Mandau - These two men need to find something else to do...Attachment 28636...Besides watching the new floor being ruined!
Reply:Originally Posted by Donald BranscomI hope those are welding glasses and not just sun glasses.Sunglasses will not protect your eyes.Those are safety glasses with the right shade for cutting... welding would be no.10-11 with a full face helmet.A trick for you.ThanksWhen you cut long lines or large curves leave a small part like 1/2 inch UNCUT every foot or so, then when you are finished you can go back and cut the  uncut small sections.Th purpose is you can prevent warping of the edge because the heat causes shrinkage.Very useful on curves and especially when cutting holes in a large sheet or portholes in a cabin of a boat.