Plasma Steel Cutting

DrDan · Jan 18, 2002

I have been considering the purchase of a Hobart AirForce 250 Plasma Cutter to cut 1/4" and thinner steel plate and wonder if anyone has used one. It seems like it does a very clean job of cutting and is better than conventional Oxy-Actylene for thin steel (less warping, cleaner cut, more precise). Of course that may all be hype. Just curious...

DrDan

RJohnson · Jan 19, 2002

The key thing about plasma cutters is that they were basically developed for nonferrous materials. You cannot cut as thick of a pice of carbon steel as you can aluminum. They are also very good for stainless steel. They can produce very smooth cuts and you can produce fairly accurate parts cut out of plate.
The one thing I would think about though is with a conventional oxyfuel torch, you can heat things you bend. Like those three points arms everyone is talking about /w3tcompact/icons/smile.gif. They are also not very portable like a torch cutting set up. You will need an electrical power source but other than that if you plan on cutting alot of gauge sheet metal then go for the plasma, it does not heat up the part as much and therefore you get less distorsion. hope this helps.

Randy

frank_f15 · Jan 19, 2002

DrDan: not familar with that particula model of cutter, but can tell u that plasma cutter is great. the one i use is dual voltage, and at 220 voltls and air press just right u can cut 1/4 plate with no problem. much smoother than oxy cutter. thinner plate is easier yet.on very thin metal u will get a slight amt of heat warp but nothing like oxy. if u are considering a plasma cutter i would imagine u already have a reg cutting and welding outfit? i only ask this because most people that do not already have need of stick or mig welder or oxy , would be ill advised to get a plasma cutter., unless the need was strictly for fine cutting. i do have a tendency to ramble on, sorry!!/w3tcompact/icons/blush.gif

DrDan · Jan 20, 2002

Thanks guys... I have Oxy-Acetylene but am going to do quite a bit of cutting of cold rolled sheet to do the sides and bed of trailers I am going to build plus a flatbed for my truck. (God I am so sick of a Topper and conventional bed on my ton truck - can't haul big items). A dump trailer whcih is not built for my best advantage is about $6000 so I figure I can afford the plasma cutter and still come out way ahead of the game money wise and have the cutter when I'm done. Also interested in building once of those minature back hoes so I should get lots of use.

Been out of metalworking for years and anxious to get back in. Have so darn many things I need to build and it is so difficult getting someone to do it "right" for you. The best welding shop around here (the one I trust) is so overbooked with maintenence of "State" snowplows in winter and mowing machines in summer that it is a long wait for anything. Guess if ya want the job done right ya gotta get into it. Anyhow, fabrication is fun and it is amazing the things you can build. On the last farm I worked on I laft him with the prettiest gate posts ya ever saw. I went back there ten years later and the gates were still perfect. Once I get the trailer done, I'll start scrounging around the salvage yards for steel. You can get some real bargains if ya keep your eye open.

DrDan

genelp · Jan 21, 2002

There was a similar thread a couple of weeks ago. If you already have an acetylene torch than you already know and have the advantages such as portability and the ability to heat for straightening and bending. If you want production capabilities and are going to basically cut sheet metal, a plasma cutter cuts much faster and cleaner with a lot less chance of warping your material. For straight cuts you can mark out your piece, clamp on a straight edge and have at it. You will need a darker tint on your face shield than you would for the acetylene torch; in fact I just used my welding helmet. When you get your plasma cutter make sure you get plenty of spare tips! You can burn one up quickly if you keep your tip to far from the workpiece. I think someone else mentioned this but I'll emphasize it; if you are going to cut stainless steel the plasma cutter is the only way to go, an acetylene torch won't cut stainless steel. Or at least for the thicknesses semi trailer manufactures use.

Good luck

Gene

Anonymous Poster · Jan 21, 2002

Dr Dan, I'm just a back yard welder, learn as I go, so this is just my 2cents. I have a Thermal Dynamics plasma cutter(I think mine is called PakMaster38, it's a 110v.). I use it alot more than the oxy/acet. setup. It's fast clean and easy to use. I can make more accurate cuts with the P.C. than with oxy/acet.

the down sides: the Plasma C. is very expensive compared to Oxy/acet .

Plasma Cutters.. cutting thickness is limited by the size of the machine you buy($$). Oxy/Acet. will cut just about any steel.

I'm told on P.C. you need to be careful of the air supply, clean and dry air or the machine will have problem. I've been using a small compressor with a moisture seperator for about 3 years and with no problems.

I don't know if it makes a difference to you, but the few pieces of aluminum I've cut, is not a clean cut. A sawzall or skill saw does a better job. I may have been doing something wrong, but for alum. I use the saw.