Air for plasma cutter

[ejm1961Tbird]

I just bought a plasma cutter and I need air supply. I can lease a size 300 cylinder for $200 for 5 years and filling it with compressed air will cost about $50. Is anybody running their plasma cutter with a cylinder of compressed air. I will use the cutter for auto body hobby work. It will not see real heavy use. On the other hand, I would love to have a nice two-stage, 60 gallon, Quincy air compressor to run the plasma cutter. However, I hate to spend a bunch of money on a good air compressor when I am mainly interested in getting air to the plasma cutter. The cutter needs a minimum of 5 cfm at 90 psi. I know I could get a smaller, portable air compressor, but if I buy a compressor, I would like to get a good one. Sooooo, are you running your plasma cutter with just a cylinder of compressed air?

 

[Bluearmflames]

Just use air compressor. It will pay for itself pretty quick if your paying rental fees and what not

 

[Cryptic1911]

I see nice used compressors on craigslist for not much more than the tank rental you mentioned

 

[ejm1961Tbird]

Good point. I probably could get a small used compressor that will get the job done for a couple hundred or so.

 

[Kev442]

Find a Speed Aire like on today's thread and you will be a happy camper.

 

[purplezr2]

Good point. I probably could get a small used compressor that will get the job done for a couple hundred or so.

Read the CFM requirements of the unit. I know that the unit I have requires 6.7 CFM at 85 PSI. I have a hypertherm 65.

 

[Jim Johnstone]

I would just buy a used compressor especially if you only need 5 cfm. Where would you be getting the 300 cf cylinder filled with compressed air and to what pressure? After that how would you regulate the pressure down to a useable level?

Sent from my SGH-I727R using Tapatalk 2

 

[zkling]

Read the CFM requirements of the unit. I know that the unit I have requires 6.7 CFM at 85 PSI. I have a hypertherm 65.

X2

Some units have a low air supply shutoff. I think you will be going through gas very fast using compressed gas cylinders. I would have to calculate that to be sure though. You could also use nitrogen if you were feeling fancy.

Sounds like a good time to invest into a decent compressor. One thing though, make sure you put a good filter on the compressor and the plasma unit. Dirty, moist air will greatly shorten your plasma consumable life ($$$$$). The motorguard toilet paper filters are pretty much standard for plasma units.

 

[diesel research]

i ran (and melted) 2 different oiless compressors. consumer grade 110 volt 30gallon junk. each did hold up for about 3 months of daily use in shop.

if you watch your duty cycles, most oiled compressors will keep up.

 

[Steroblan]

If you use a cylinder for air supply you will be out of business for the day when it is empty. A decent compressor will be your best friend and will service many auto body uses and other hobbies.

 

[HAP]

One alternative is to use SCUBA tanks. Have at least two.
More than just one type of use.

HAP

 

[Jim Johnstone]

One alternative is to use SCUBA tanks. Have at least two.
More than just one type of use.

HAP

Not a bad idea but they wont last long on a plasma and by the time he buys 2 and get a regulator setup to get the air to a useable level and then has to take them for fills all the time he would be further ahead to just buy a decent 3-5 hp air compressor.

Sent from my SGH-I727R using Tapatalk 2

 

[gte718p]

Unless your in the middle of no where with just enough power to run the plasma get a compressor. Does that make me 8 or 9. You could buy a top of the mine compressor for the time, energy, and expensive of buying a bottle setup and carting it to be filled a couple of times.

Even the oiled HF 20 gallon for $300 will more then keep up with a plasma cutter.

 

[5mall5nail5]

Buying a cylinder of compressed air to run a plasma cutter is insane.

Seriously.

 

[theoldwizard1]

...The cutter needs a minimum of 5 cfm at 90 psi. I know I could get a smaller, portable air compressor, ...

I don't think so ! You are going to need a minimum of a twin cylinder 3 HP (that is real HP, not the "peak" BS that you see in a lot of places) and a 30 gallon tank to get 5 CFM @ 90 PSI.

 

[rlitman]

Buying a cylinder of compressed air to run a plasma cutter is insane.

Seriously.

Pretty much. If you managed to get all 300CF out of that cylinder in the top post (you'd be lucky to get 80% in reality), AND your plasma cutter actually only used 5CFM (which is utter BS, plasma cutters generally require a 5CFM compressor, but because you don't cut continuously, you can get away with a smaller compressor), then every hour of cutting would cost you $50 in refill air.

If you're off the grid, cut with oxy-acetylene. If you're not, then get a compressor.

 

[buening]

Here you go (local): http://knoxville.craigslist.org/tls/3818669039.html

 

[ejm1961Tbird]

Okay, okay, you talked me into it. I'm going to spring for a good Quincy air compressor.

http://www.aircompressorsdirect.com/Quincy-2V41C60VC-Air-Compressor/p855.html

 

[purplezr2]

Okay, okay, you talked me into it. I'm going to spring for a good Quincy air compressor.

http://www.aircompressorsdirect.com/Quincy-2V41C60VC-Air-Compressor/p855.html

I love how it went from a couple of cylinders to a 1400 dollar compressor

 

[ejm1961Tbird]

That is great how that worked out, isn't it?!

 

[Ryf]

I dont have a plasma cutter, but I borrow my Brother in laws cutmaster 42 from time to time (read as, once a month minimum for a week at a time). I have a "2hp 2 gallon" pancake compressor, probably 1.5 hp actual at best but it more than keeps up for "structural cutting" if you are going to do sheets and pattern cuts I'd say you need more but then you also need a pretty high duty cycle cutter. we used the small compressor and cutter all day intermittent to scrap a bunch of metal, we never had to wait for it to keep going.. not saying bigger isn't better, just saying to those who are considering and want a hobbyist perspective, if your not doing sheet patterns, its not that much air even cutting 4" angle 1/4" thick.

 

[TwoInch]

The cutter needs a minimum of 5 cfm at 90 psi. I know I could get a smaller, portable air compressor, but if I buy a compressor, I would like to get a good one.

good choice on the real compressor.

tool usage cfm at 90psi is not comparable to compressor SCFM at 90psi, the two are different and do not translate. if a tool manufacturer is claiming 5cfm at the tool, then it is actually using more like 30cfm at 90psi at the tool. its marketing gimmick ********.

compressor SCFM at 90psi is a whole different animal. it is taken at the intake of the pump, and has nothing to do with what you end up getting out the other end of the tank out of the regulator at pressure(90psi). a 10 SCFM at 90psi compressor is taking in 10 SCFM of uncompressed air. the difference of the 40psi and the 90psi compressor ratings is because the pump is able to pull less air into the intake as the PSI rises on the receiver side. the compressed air expands as the piston goes down for another gulp, allowing less into the intake side.