Plasma Vs Torch

[TomNTex]

I'm looking at a Lincoln ProCut-25 for completion of a fencing project. This plasma cutter is rated up to 3/8" for mild steel. Just wondering how it would work for cutting saddles out of 2-3/8" tubing. If the pipe is fairly clean could I expect the plasma cutter to be an advantage over the acetylene torch?

Thanks
Tom

 

[Lefty]

Dunno if pipe cutting would be the venue for a plasma cutter or a torch to be efficient/clean,since that type of cutting depends on the air/oxy jet blowing the molten slag clear of the cut...just seems to me that you'd have a lot of buildup"inside" the cut pipe,also(and I'm no expert),wouldn't you have to have to cut all the way around the circumference of the pipe w/plasma as close contact to point of separation is needed?After all as I see it(maybe wrong)both methods are the same other than the plasma cutter is intensly pinpoint in its heat,where the torch is much less controllable as to collateral heating?

 

[Anonymous-0]

No. If you're only going to be cutting steel, a cutting torch is a better choice. It's way cheaper, more portable and can be set up to cut any thickness you need. A plasma torch needs an air compressor as well to use it and plasma torches go through consumables(electrodes, swirl rings, etc.) a lot faster than a cutting torch. Plasma has an advantage on thin material because it doesn't cause warping of the metal and can be used on any type of metal. If you needed to cut a lot of aluminum or stainless then a plasma would be an ideal choice. For cutting tubing it would be a waste of money and what would you do if something came up where you needed to cut a thicker piece of steel? When cutting your tubing, cut vertically up so the slag doesn't get in the way of the cut. If the cut is close to the end of the pipe, you can knock some of the slag off after half of the cut is complete. You could do this step with plasma as well. A really clean tip will make a big difference and might not have much slag built up. Dave

 

[jose bagge]

Tom, I gotta tell you that after years of doing roll cage work in stock cars with lots of saddle cuts (probably 48 in a set of door bars alone), I still find that the best way is with a chop saw...set it up for an angled wack about a 1/3 of the diameter up, rotate 180 and do it again. I even bought an over-center tubing knotcher that would do it in a single pull, but still when the chop saw route almost all the time. You'll end up grinding anything you oxy cut clean, and might even do it with the plasma- the chop saw will be ready to weld.

 

[Welding man]

I am so glad after all these years of debating with people about the great benefits of plasma over a conventional torch, that some of you actually agree with me. I have tried plasma a few times on different jobs and am not impressed. I have been in the welding business for over 30 years and I do not own a plasma. If I can't cut it with a torch or a carbon arc I saw it.

 

[Orangefever]

I have a miller plasma cutter and I love it my cuts are neat and clean and the metal doesn't get nearly as hot as a torched cut gets also when percision count if you cut a straight line you can see your heart beat in the cut through the pulse in your thumb My only recommendation is if you but one get a name brand generic ones don't usually last long

 

[moonlite 37]

I have cut a considerable amount with a torch and ran a welding shop with from 6 to 10 welders and I have never seen a REALLY good torch man work. I am also not very good. I have seen work that was done by experts but never got to watch them work. It is a difficult skill to develop. I know any idiot can make one piece of steel into two parts but that does not make him a good torch man. Also it does not take as much skill to use a plasma cutter but the best results will not be as good as a cut by an expert torch man can make.

 

[504-2]

I always used a chop saw on tubing(it was all I had)But all of the shops I deliver to that have bought Plasmas only use a torch for heating rusty bolts. If you are haveing trouble with a plasma,the first thing to check is the air filter they will not work worth a hoot with out DRY air.

 

[Anonymous-0]

I don't know why people think a plasma torch is the cats meow. On certain jobs they are but I can do a much nicer cut with a regular cutting torch. The best cutting I ever saw was at a trade show. There was guy from Smith's doing cutting demo's. He was cutting peoples names out in steel plate. He rested his left hand on a fire brick so he could steady the torch and used his right hand on the trigger. You'd swear his cuts were done with a mechanized torch. He put a tip cleaner in the cutting jet once before he started the next cut. The trick is to be super comfortable and make sure that the hoses are free to move with the torch and the tip is clean, the right size, with the right gas pressures. I can cut pretty good but on longer cuts, I sometimes forget to breath properly because I'm concentrating too much on getting a nice cut. A lot of times, I'll put the hose over my shoulder and leave some slack, so it doesn't get hung up on something while I'm cutting. It takes a lot of practice. Another thing to remember is to cut on the edge of your line instead of the middle. Cutting in the middle will make your pieces too small. Use a sharp soapstone to mark your line as well. I've seen guys try to get an accurate cut with a line that's well over an 1/8" wide. The finer the line, the finer the cut. I think Plasma torch just sounds like a really cool thing to have for some people. They are excellent for some jobs but on thicker steel, I'll take a cutting torch anytime over a plasma. Much easier to see what you're doing with better control. Dave

 

[T_Bone]

Hi Tom,

There is a reason why they sell $2000 plasma's and $5000 plasma's. Dragging either one around in a very dusty environment would not be a good thing. Then there is the set up cost of all the extra componets needed, air compressor and high use consumables and or He, Ar, N gas.

I can saddle a 90º pipe T with a 5" side grinder pretty darn fast without a torch.

Until you get use too seeing a saddle cut at the correct dimensions, make a SM template to slip over the pipe.

The most cost effective for a beginner/experienced pipe fence builder would be a mechanical pipe notcher.

T_Bone

 

[Puddles]

I would love to see a cost comparison between a plasma and O/A torch. In dealing with carbon steel only, I’d venture to say in excess of 95% of the welding fabrication world a plasma will never pay for it’s self. The initial cost alone is staggering! Then start buying consumables!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I’ll bet the average guy could buy a Victor Journeyman set, O/A tanks, port-a-band saw, chop saw, 4-inch grinder, and a box of soapstone cheaper than a small plasma. (Especially if you factor in the cost difference in consumables for the plasma over the life span of the plasma).

I will say, 98% of the time I’d rather use a plasma torch with a scarffing tip to go after a bad spot in a weld than an air carbon arc torch. A plasma torch is like laser surgery!
Don’t get me wrong a carbon arc set up with a 500-amp machine, and a 185-compressor can flat move some metal! ;o)

 

[glennster]

tom, i'll give you my thoughts, for what its worth. i worked in a fab shop for a while, and used plasma quite a bit, also oxy acetylene, oxy propane, band saw, and chops saws. we did predominately mild steel fabricating. we cut a lot of 1/8 inch up to 1/4 inch 4x8 foot steel sheets, the plasma excelled at that. for round, square and rectangular tubing, they went in the band saw. really big stuff, odd cuts ect, the oxy acetylene or oxy propane were the choice. for notching tubing, i'd grab the torch.

 

[Anonymous-0]

I was fortunate enough to have a dealer looking for me and I bought a good unit off lease a few years back for major work on an aluminum truck grain box.
The young neighbor who helped me could do magic with that thing. I can't. I don't know if it's age, vision, steady hand, or what you're used to. About the same time someone tried to sell me on a wire feed welder. I couldn't really get the hang of that either. I basically use my oxy/acet. torch and a stick welder.
So- I can't justify owning the plasma except that the truck box job paid for it(couldn't get anyone else to do what I wanted) I was hoping neighbors would make use of it in special situations but that hasn't happened.

 

[RickL]

not if you are good with your torch. Had a Plasma cutter for couple years,sold it. Yea it was nice but it didn't do anything whole lot better than I could already do with the torch. Don't get me wrong they are nice,different learnig curve again,but if you know how to use torch correctly you won't be able to tell if it was torch cut or plasma cut other than the heat scor shows little more. If you do really really thin stuff all time yes they are nice for that otherwise torch does fine

 

[Mel in SW Iowa]

I cut and fabricate 10 ga and 3/16" sheet steel in 1" to 40" cuts.

I have tried some plasma cutters, but the cost
per cut is too expensive for my use.

I use a cheap 7 1/4" cold cut saw with an edge guide for a lot of my straight cuts and a Purox mid sized O/A torch with a #3 cutting tip on curved cuts.

I often use a Purox sheet metal tip that only has
one preheat hole on shorter straight cuts. It gives a nice straight low distortion cut that looks a lot like a plasma cut.

 

[ohfred]

Read all the posts and saw a lot of the guys referring to a good torch man. What is a good torch man? Well I guess you could describe him as a steady nerved fellow who knows his equipment and knows how to set it up with the different tips and pressures. Along with that, I'll tell you that I have a machine that is called a Heath Ultragraph that is a torch mounted on a pivoting arm setup with a Smith torch with 200 series tips and if you look in the book and set the guages to the recommended pressures and fire it up and go to cutting, and then give the guages a final tweek while cutting, you will notice that the sparks coming out of the kerf will shift to a 45 degree angle AHEAD of the torch. When you get this condition, there will be no slag on the parts, only a bit of scale that can be removed with the thumb nail. But you must have the right tip and pressures for the steel being cut. So, go ahead and give it a try...while someone is cutting with the hand torch, try tweeking the guages and see if you can find this condition. Give it a fair test with new (clean) steel and see if you can become a GOOD torch man. ohfred

 

[Brian Jasper co. Ia]

If you can find the right guy, he can cut with a torch and it will look like a bandsaw did it. I've only met one guy that could do it. Prior to that I'd say show me. For the rest of us, a plasma cutter is the way to go.

 

[Anonymous-0]

If the sparks are coming out a 45deg. angle, it is close to losing the cut but on a motorized torch, with very steady speed, will usually cut really nice. The sparks can be straight down and still leave no slag. If the slag knocks off easily with a piece of flat bar is OK too. Proper size tip, right cutting pressure, comfortable postion, and steady hands can turn you into a good torch man with enough practice. I can cut a straighter line than I can draw one. I don't like cutting boiler plate(SA516-70) too much because the mill scale pops off and hits you in the face and makes your line go away. You can grind it off but that takes a while. Most people are in too much of a hurry when they want to cut something. They just grab the torch with what ever tip it has and don't even bother checking if they get a nice straight cutting jet. 5 seconds with a tip cleaner can make a huge difference but only go in once or twice. Putting a tip cleaner in too many times can oval the cutting jet. Dave

 

[Anonymous-0]

In addition to deafening anyone not wearing really good ear plugs. 500 amps on a gouger makes the cables jump and dance pretty good too. Dave

 

[ohfred]

Dave, I don't see anything wrong with your method but, I will add if you need to cut that real straight line with that old popping scale that hides the line from you...try using a center punch to make witness marks along the line and be happy. ohfred

 

[Gary from Va]

In my shop, I leave the excess welding cable hanging on steel hooks while I'm air arcing. I like to hang spare oxy. bottle caps on the hooks, strike the arc, and listen to them ring as they bounce around on the hooks.

 

[Anonymous-0]

Ever put your hand on the cables when someone else is gouging? It feels like high pressure water going through the cable. Would be a good way to show how DC current moves from Neg. to Pos. Dave