Plasma Cutters

Several of you guys have made the point that it makes life a lot easier to get a high quality MIG welder. But what about the Plasma cutter. Will any old thing do, or is there going to be a big difference between cheap and not-so-cheap on this kind of job?

I bought the Hobart from tractor supply. That thing is an awsome little machine. However, this is the first and only plasma that I have ever used. So if there are better I guess I just dont know any better. But yes if you plan on building multiple gasifiers it is a must have machine.

Which Hobart did you get?

Hi Matt,
Is this the one you are referring to?
http://www.tractorsupply.com/plasma-cutters/hobart-airforce-reg-250ci-plasma-cutter-with-built-in-air-compressor-3808889
I’ve got one, it’ a bit on the lite side, Definitely not a production machine but ya can’t beat it for portability.
The on-board compressor is a great idea.
TerryL

Hi Kyle
I had a plasma cutter years ago it was not much good So for this project i ask Wayne what kind he had I figured as much as he uses it He would know and sure enough it was a good guess
the one i got is a lotos LTP 5000 it has a pilot arc so it will start on dirty metal
So far I love it just playing around with it till i get time to start building in earnest but it cuts diesel truck pistons which are thick alum. with stainless inserts besides thin stuff
Good luck
PS
Thanks for the advice Wayne

The Lotos does a good job, it falls into the “cheap Chinese” category but it’s plenty good enough for what we need to do. One perk is that it runs 110 and 220, so if you’re clever with the wiring you can take it with you to a friends house and use it on any outlet. It uses external air, which is IMO pretty much a requirement - given how much air my big compressor puts out, and it running constantly to keep up with the plasma, I can’t imagine this working with an onboard compressor, the equivalent of a tire pump. But that’s me being narrow-minded, obviously they exist and work fine.

Best part is the price, brand new $300 shipped if you watch Ebay. They perform fine, watch out for consumables though, they will take a bite out of your wallet (true for all brands). Be sure to have extras around because you’re sure to mess up a few getting started.

Yes its the Air force 250 I couldnt remember. But it does a good job we use it daily. We cut mostly 14 ga. steel with it. It will cut up to 1/4 inch thick. My sugestion is go to your local weld shop and get the info from them. There are better ones out there.

Actually the onboard compressor works very well on the hobart. The other thing I like is you can get all the parts for it from the local Tractor Supply store and in my area they are open on Sunday. Plus they are just down the road form us:)

Yes i kinda felt bad buying china until an old pipeliner friend of mine took me down to the local weld shop
This was last year i was in the market for a combo unit but ended up not buying anything back then
His son worked there we poped the cabnet on a good ol usa brand and guess what it had for insides That tells me there is a lot of hanky panky going on in this buy usa label.
So for the money and the fact that i could bust a hammer with a chicken feather I think it’s good enough for me
good luck
Tom

Air Dryer? It seems that with an onboard compressor there might be a problem with humid air, whereas with an external compressor one could run the air through a long run of sloping pipe, or even through a tank in a refrigerator, or a filter/dryer combination, such as http://store.millerwelds.com/commerce/product?ProdID=300491 When I run my sandblaster when the relative humidity is high, the nozzle plugs with wet sand. Doesn’t wet air ruin the plasma cutter “consumables” quicker? There are good days for TIG welding, when everything goes smooth as butter, and on a humid day, the purple glow forms around the electrode…and you spend lots of time sharpening the tungsten electrode!

Im not sure but I dont think the hobart actually use an air compresor. I think it is really a high flow diafram pump. I never have to wait for to pump up even right out of the box. You pull the triger and go.

Spot on with the air drier. This is a good idea anyway, but it’s critical to a plasma cutter. Even the cheapies come with a little filter/drier which doesn’t work very well but it’s a step in the right direction. I want to apply some of the cyclone designs that I learned for gasification to the problem, I think that would do a good job. Chris Franklin has a picture of one somewhere that he built.

I use a Thermal Dynamics Cutmaster. Not cheap but a good tool. Now let’s not forget saber saws, sawzalls, band saws,air chisel and cutoff wheels, are also good for clean cutting. I always use the saber saw on propane tanks and the air chisel on gas tanks or fuel drums. BE SAFE

A friend of mine recently purchased an ebay 3 in 1 plasma cutter. (stick, tig, cut) It worked well enough, for me, to build his gasifier; then I fired it up and it Did Not work anymore. We have not figured out what is wrong with it yet. The tig and stick work…just no more cut.

I do have a large cooler and water traps installed on my compressor; so I don’t think moisture was an issue. Just cheap inverter type machine.

I have used much larger production machines and never had any problems with them. I am not a fan of the smaller inverter plasma cutters.

Hi it could be something simple
If it’s a lotos there is a trouble shooting guide on uweld.com/help
good luck
Tom

I like most of you don’t have the money to blow on expensive equipment but think I’m going to hold out and buy the hypotherm powermax 30 its American made consumables are suppose to last a longer time then the cheaper units it is also very small .Yes its going to set me back a grand but… should last for many years to come

Hi Tim; I have the Hypertherm Powermax 45 that I purchased from Airgas Welding Supply. It came highly recomended and has worked well so far. I can’t emphasize enough to have multiple moisture filtratration.It is the worst enemy of a plasma cutter.The Hypertherm had a built in moisture trap inside and I have another bowl trap and a special cartridge filter that I got from airgas. It has a very dense material like filter inside a heavy duty canister. The guy at Airgas said in his opinion this filter is a must have if you want your machine to last.I am glad I went with the 45 for the extra capacity, but also cost $1800.00.(OUCH!) But quality tools pay off in the long run. Dan

I have a cheap 40 amp China made and sold by Parker Metal Products in Arizona…I have had this unit since 2007 and I cut every day with it…I paid 416.00 then and have put about that much in consumables… and new torch and ground clamp…I am very happy with mine…cuts 5/8 and sever cuts 3/4…and FLYS through sheet metal…

I started out with a borrowed Hypertherm Powermax 65 and when I had ti give it back I bought a Lotos for around $300. The Hypertherm used no consumables while I had it while the Lotos uses a lot. For a hobbyist I would recommend the Lotos. Anything more I would recommend biting the bullet and buying the Hypertherm.

hi John
i don’t get on here much any more with the family illness and all
But i saw your post thats about what i saw with plasma cutters My cuz has a hypertherm however it was only a 30 or 35 amp unit if i turn my lotos down to 30 amps it does a lot better but i usually run it wide open i abuse it pretty bad i cut spring bolts on trucks and all kinds of crap that i guess it wasn’t meant for so i use quite a few tips
BTW how is your truck doing? I had to put my plans on hold for now
Tom

Hay Danny thanks for the info on the moisture filtration I will definitely talk to airgas when I get mine. First I have to buy the truck I’m going to use for this hoping to do that in the next few days