Plasma cutters

[Gregor 4,838]

School me on plasma cutters. Do they require a LOT of air for an extended period, like a sand blaster, or not that much? 

Thanks  Greg

[ebinmaine 63,349]

This here Bear 🐻 will be following along... 

[squonk 39,037]

Look on line at a particular model you're interested in and see the SCFM specs of it.

 

  To be precise, the air pressure required for a plasma cutter is about 4-8 SCFM at 90-120 PSI. This plasma cutter air pressure is a generalization for cutting steel between 3/8" and 7/8" thick

Edited September 6, 2022 by squonk

[Gregor 4,838]

is about 4-8 SCFM at 90-120 PSI

 

So are we talking 1/2hp compressor, 10 gallon tank?  2 hp compressor, 15 gallon tank?  5 hp compressor, 60 gallon tank? Those numbers mean nothing to me.

[Bill D 1,628]

How thick is the metal you plan to cut?  Some machines have built in air compressors.  My experience with air compressors and plasma cutters is the bigger the better.

[Heatingman 941]

60 gallon tank or better for continuous or near continuous use. But as pointed out above, you gotta look at specs. 

 

For reference my 60 gallon tank is rated to 11.5 cfm at 90 psi

[Heatingman 941]

54 minutes ago, Gregor said:

is about 4-8 SCFM at 90-120 PSI

 

So are we talking 1/2hp compressor, 10 gallon tank?  2 hp compressor, 15 gallon tank?  5 hp compressor, 60 gallon tank? Those numbers mean nothing to me.

The ratings are generally written in plain easy to find english often a little chart on the tank.

[Ed Kennell 35,949]

Rule of thumb for small compressors.     1HP for each 4SCFM   

[Bill D 1,628]

You will also want extremely dry air for a plasma cutter.  Several post compressor water traps and filters will be needed.  If you go with a big compressor, consider adding an air cooler and water separator in the line going from the pump to the tank.  Several videos on YouTube that show how people have done this.  Like with most things on YouTube, use your judgement and proceed at your own risk.

[Bill D 1,628]

You will also want extremely dry air for a plasma cutter.  Several post compressor water traps and filters will be needed.  If you go with a big compressor, consider adding an air cooler and water separator in the line going from the pump to the tank.  Several videos on YouTube that show how people have done this.  Like with most things on YouTube, use your judgement and proceed at your own risk.

 

I had a plasma cutter, but I sold it to a friend.  I didn't use it enough.

Hypertherm makes some of the best machines on the market, but they're pricey.

[sjoemie himself 2,923]

First: you have to decide how thick the material is you would want to cut.

Second: based on that you look for the plasma machine you want to buy. That dictates the cfm needed.

Third: based on that you decide what kind of compressor you need.

 

This is IMHO the only way to do it right, or atleast that's how I purchased my plasma machine and compressor.