Compressed air for Plasma Cutter

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My Hypertherm Powermax 45 is ordered from Welders Supply, thanks in large part to what I have read on this forum. I hope to have it by next Monday and can't wait to start cutting everything in sight  I am piping air into my 12 x 30 backyard shop using 1/2 copper pipe from my old Craftsman 2 HP, 26 gallon compressor which delivers 6.4 CFM @ 90 psi according to the label. I wired a 220 line to the compressor "closet" located outside the shop for when this compressor dies. I am now wondering about the filter and regulators. I will install a drain at each drop. I am in south Florida so moisture will be a problem. I would appreciate suggestions on what filters, gauges and regulators for this system. Thanks, Mark
Reply:Living out here in the Great American Desert I'm sure I don't have the problems with moisture that you encounter. Motor Guard makes a great air filter/dryer that can be attached to the rear of your plasma to get whatever moisture still left in your air line after the upline filters have had their chance at it. EDIT: Here is a quick and dirty reference for running your lines. Finally, a refrigerated air dryer may be needed in your area due to the heavy humidity you experience. Wait awhile and give the Motor Guard a try while seeing how well your consumables for the plasma do with it before going with the refrigerated dryer...you might be able to save some money.Last edited by WyoRoy; 01-06-2015 at 12:00 PM.Lincoln PrecisionTig 275Miller 251Miller DialArc 250Bridgeport millHossfeld bender & diesLogan shaperJet 14 X 40 latheSouth Bend 9" 'C'Hypertherm 900Ellis 3000 band saw21"Royersford ExcelsiorTwo shops, still too many tools.
Reply:Since your Compressor is sized at about the same flowrate that the Powermax45 requires (6.0 cfm@90 psi) the compressor will run at about the same duration as the Powermax is cutting. The more the compressor runs, the more water vapor is produced, and much of it stays in the receiver (tank). Put an auto drain on your compressor...this will drain the moisture from the tank on every cycle....and while it will not eliminate all of the moisture from your air system...it will be a great first step. Harbor Freight has a $9.95 auto drain assembly that fits most compressors.Run about 20' of copper pipe from your compressor....inside your shop or in a shaded area. At the end of this pipe you should have a tee with a low leg and a high leg. The low leg should have a drain......the copper pipe will reduce the air temperature a bit....which will condense the aerosols of water into larger droplets. Most of these will run down the low leg of the pipe and you can drain it daily. At the upper leg install a coalescing filter bowl....which essentially spins the moist air and slings the heavy water particles to the outside....this will get rid of more moisture. Take the air for your plasma off after this coalescing filter. It is a good idea to install a pressure gauge right at the inlet to the plasma...this way you can insure that you have sbetween 90 and 120 psi entering the unit...when air is flowing at all times. Check the onboard filter bowl on your system periodically for signs of moisture...it has an auto drain however you will see if any moisture is getting to the plasma. If the bowl looks like there is moisture getting to this point...you may need to look at further filtration to be installed just before the plasma. An absorbing filter (like a motorguard) is adequate for small amounts of moisture. For hobby type use the above is usually adequate. When your compressor dies...get a larger unit that runs at a lower duty cycle....and you will produce less water.Jim Colt  Hypertherm Originally Posted by Mark SMy Hypertherm Powermax 45 is ordered from Welders Supply, thanks in large part to what I have read on this forum. I hope to have it by next Monday and can't wait to start cutting everything in sight  I am piping air into my 12 x 30 backyard shop using 1/2 copper pipe from my old Craftsman 2 HP, 26 gallon compressor which delivers 6.4 CFM @ 90 psi according to the label. I wired a 220 line to the compressor "closet" located outside the shop for when this compressor dies. I am now wondering about the filter and regulators. I will install a drain at each drop. I am in south Florida so moisture will be a problem. I would appreciate suggestions on what filters, gauges and regulators for this system. Thanks, Mark
Reply:I have one 20' after my compressor and one on my plasma.  Inexpensive and work good in the middle of a humid summer. http://www.aquachekfilters.com/
Reply:I've found unclean and damp air will make the best plasma cutter act like a pos. I run a large pre filter (100 micron), then coalescing filter, then a camair ct30 desiccant dryer, then another post filter. Keeps the air very clean and dry. Before putting that system in, I was actually pretty fed up with my plasma. Afterwards it was like the plasma was a different machine.  In florida, I'd look for a refrigerated dryer used on cl or ebay.  With the warm humidity there, I think you'd eat up a desiccant dryer pretty quickly.  Still put a pre and post filter before and after the dryer. You bought a nice plasma, feeding it bad air is going to hold the machine back.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow