Need advice on Gas cutoff Saw?

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I have a job for a guy that has large pipe ranging from 24-36 inch in diameter.  The thickness ranges from 3/16 to 3/8 inch.  Basically I cut square looking holes out of the pipe and make somewhat of a inspection door.  Kind of like cutting a door for a BBQ pit etc. He uses them for inspection purposes for whatever he is doing.  These doors are sometimes 18" square or as big as 36" square.Anyways, the guy is fine with me doing it with a torch as long as the door is not warped real bad and its somewhat clean looking when Im done.My question is, has anyone ever used a gas powered cutoff saw on something like this???Im just wondering if the torch is easier on the operater and just as fast as the saw.  Or does the saw cut faster and can handle the thickness I stated...The saws are a little expensive but Im just wondering if It will be worth it.... If there is a specific model or brand thats good let me know also.
Reply:The torch will be faster. And less agonizing.
Reply:I think you would do better with plasma or a torch than a gas saw. Plasma with its limited heat transfer would be ideal in my opinion.I run gas saws all the time for cutting concrete. Stihl and Partner are usually the two biggest names that you see used all the time on most job sites. They would be my recommendations. Makita has one, I have never used one but the generally have a decent reputation for most of their tools. I have a 14" Partner and I love it. I find the Stihl's either under powered or very heavy. You will most likely be looking at 12" or 14" saws to get an abrasive blade to match. Be advised there are blades for the gas saws and blades for the std chop saws. I forget which  is rated for the higher rpm off the top of my head, but be sure and use one rated for at least the rpm of the saw. Things get messy fast when the blades come apart. ( Don't be surprised when they do.) The other problem is that the blades wear down fast. I cut rebar with the saw from time to time if I have to and use the abrasive blade. If I need to cut 4" iron pipe I will need at least 2-3 blade to cut all the way thru do to blade wear. I have an old junk diamond concrete blade that I use on 4" iron pipe because it will not wear down as I cut, but that blade would be VERY expensive for cutting steel.The saws are VERY noisy and give off a lot of fumes, something to consider if you need to run the saw indoors and do a bunch of cuts.I would look at renting vs buying. Most good rental centers will have the saws for rent. If he has a scrap piece of pipe you can give one a try and see if it will do what you want.chadwickz71 where are you located?
Reply:with a gas powered saw you are gonna have alot of trouble cutting a nice square hole in pipe.I use a stihl saw all the time, they are heavy, they are loud, and generally not fun to use, but dont get me wrong, they do have there place.Plasma would be the best, but you have to have available the power to run it and either an air compressor or a bottle for it.  Id personally just use a torch with a 1-1-101 tip and be done with it.  Oxy fuel torches can produce nice, neat, clean cuts, but thats up to you and your hands.Last edited by drivethruboy54; 06-07-2008 at 08:14 PM.
Reply:The blades for the gas powered saws are rated higher rpm than the electric cut off saw blades.You would be able to do what you want to do with a saw but you are going to leave quite a gap,dont know if thats a problem.Personally i like the saw more than the torch.I cut lots of pipe and i am pretty good with the saw.Best saw made hands down is the TS400 Stihl.I dont know about using 2-3 blades for a 4" pipe?I can normally cut a 48" Ductile iron pipe with 2-3 abrasive blades,we use diamond ductile blades mostly now though.If i couldnt get at least 10 4" cuts out of 1 blade i would switch brands.
Reply:Originally Posted by brh1969The blades for the gas powered saws are rated higher rpm than the electric cut off saw blades.You would be able to do what you want to do with a saw but you are going to leave quite a gap,dont know if thats a problem.Personally i like the saw more than the torch.I cut lots of pipe and i am pretty good with the saw.Best saw made hands down is the TS400 Stihl.I dont know about using 2-3 blades for a 4" pipe?I can normally cut a 48" Ductile iron pipe with 2-3 abrasive blades,we use diamond ductile blades mostly now though.If i couldnt get at least 10 4" cuts out of 1 blade i would switch brands.
Reply:Another option might be to use slicing wheels mounted in a hand grinder.They're fast and accurate, especially on thinner work.
Reply:Hmm, I guess i'll just stay with the Torch or maybe get a plasma.I might take a look at the Spectrum series.
Reply:BY THE WAY.......Is there anything I can buy that I could rest the torch in to help "Steady" my hand a little. Im not real shaky but it would be nice and easier on those long cuts to rest the torch in some kind of saddle maybe that would allow for a super smooth cut..Any ideas.
Reply:to get proficient with a torch takes time, just like welding.  You need to find a way to steady yourself, and get comfortable, just like welding. Im not sure how well it would work, but you can try a flange wizard burning bar.  They are for cutting straight lines, mostly for plate and h beams.  I find when i dont use a burning bar, my cuts are smoother, and there is almost no slag to knock off when im done.When we cut off big pipe piles, we wrap them in pipe wrap, mark the line and cut them free hand, and they had better be straight, smooth, and ready for the splice, or else...
Reply:I have a Stihl TS400 I used for masonary work when my landcape company used to do that kind of work.  Great saw for the money.  Damn near bullet proof.  I really hate cutting steel with it.  Because unless you are using it in a flat postion the rotational force will really thought you off blance.  On the fire dept we used partner saws with rescue blades in the, (basically will cut anything, metal, concrete, wood,)  The only safe way to used them is on a flat roof or out of the bucket of a ladder truck.   Which is why most fire dept now run the stihl rescue saw or the cutter's edge.   Its a carbit tipped chain saw with a dept gauge.Lincoln 300 Vantage 2008300 Commander 1999SA250 1999SA200 1968Miller Syncrowave 200XMT350MPA/S-52E/xr-15Xtreme 12vs Millermatic 251 w/30A  Millermatic 251 Dialarc 250 Hypertherm 1250 GEKA & Bantom Ironwokers
Reply:Originally Posted by chadwickz71BY THE WAY.......Is there anything I can buy that I could rest the torch in to help "Steady" my hand a little. Im not real shaky but it would be nice and easier on those long cuts to rest the torch in some kind of saddle maybe that would allow for a super smooth cut..
Reply:Originally Posted by denrepTorch cutting will probably be your best choice. A cut-off saw buried deep in 3/8 pipe is scary. Lots of friction on the wheel sides, one twist or pinch and the blade is going to break apart.
Reply:DSW,i agree with ya about the feel of the older Stihls.We had TS 350s for years and it was hard to get used to the 400.The 400 is actually lighter than the 350 according to Stihl.It sure dont feel like it.Ductile iron diamond blades are the cats ***,at least twice as fast as abrasive blades,im guessing on average they last as long as 100 abrasive blades depending on class of pipe.Weve been gettin em lately for about 70 bucks.Ive never used a partner saw but ive heard good things about them.Our saws thake a beating and get the guts ran out of them,Stihls have always sttod up pretty well.
Reply:Drivethru,saws dont kick bad if you know how to use them.I dont agree with your comment on i dont care how big or strong you are.Im 5'8" 165 and ive never had a saw kick on me that i couldnt handle.If you get hit in the face you got your face to close.Not saying it cant happen.Never heard of these saws being designed for flat?Never seen a flat piece of pipe.Normally when a saw pinches or binds it gets stuck not kick,again not saying it cant happen.Bot i am also very very experianced with these saws,i can tell if a saw is getting ready to pinch or bind by the sound of the engine.
Reply:Originally Posted by brh1969Drivethru,saws dont kick bad if you know how to use them.I dont agree with your comment on i dont care how big or strong you are.Im 5'8" 165 and ive never had a saw kick on me that i couldnt handle.If you get hit in the face you got your face to close.Not saying it cant happen.Never heard of these saws being designed for flat?Never seen a flat piece of pipe.Normally when a saw pinches or binds it gets stuck not kick,again not saying it cant happen.Bot i am also very very experianced with these saws,i can tell if a saw is getting ready to pinch or bind by the sound of the engine.
Reply:Oh im sure it happens,stuff happens all the time.In 21 years in heavy construction i have never seen anyone hurt by a saw kicking and that is being around them almost every day.I would much rather deal with the "kick" of a gas saw than the kick of a 9" grinder.Our company has pretty much banned big grinders.We had like 8 recordable accidents last year and 6 of them involved big grinders.I still have one just because the safety mamager doesnt know i have it.
Reply:9" grinders are the devil, ive spent a long time with one in my hands, they are scary, and the bosch ones have the most torque out of the ones ive used, they definitely will kick if you dont pay attention.