QUALITY CUTS ON ALUMINUM
Q. What is the best way to achieve a quality cut on aluminum using a CNC
plasma. I have a Hypertherm Powermax85 and have tried using 100 percent argon
instead of compressed air; however, I couldn’t get the parts to cut. I have
read about using helium also. Is that a better option?
A. You do not mention what thickness you are cutting, so I cannot help
you select the best power and cutting parameters, however, no matter what
material or thickness you’re cutting, my advice is always the same: use the
settings found in your owner’s manual. All of our manuals contain very detailed
cut charts, including cut charts for aluminum. Follow those charts and you can't go wrong.
As far as your cutting gas, you have two choices: compressed air or
nitrogen. Those are the only two gases that can be safely used with any air plasma system, including the Powermax85. The gas flow circuitry on your
Powermax85, as well as the fact that yours is a gas cooled (not liquid cooled)
torch, makes the use of any gas other than air or nitrogen potentially
dangerous. For this reason, Hypertherm does not recommend using any other gases
with this system.
Neither argon nor helium is used commercially as plasma cutting gases.
Argon is often used for plate marking at very low power levels, provided you
have a system like our HyPerformance HPRXD designed to use that type of gas. These
gases are not used because they do not develop an aggressive enough plasma arc
for cutting, although argon and helium could have some use as a shielding gas.
In addition, we do have products in our plasma cutting line that can use
premixed levels of argon and hydrogen for aggressive cutting of stainless and
aluminum from 3/8” to 6” thick at power levels up to 750 amps.
I've included a few pictures below to give you an idea of what cut quality to expect. These are of aluminum cut in my shop with a Powermax85
using air. The thicknesses are 3/16” and .080”. I am happy to discuss this further so feel free to contact me at
jim.colt@hypertherm.com.
Jim Colt
Hypertherm's Jim Colt is an avid fabricator who has worked with plasma cutting systems for more than 35 years. He is the author of many articles and
white papers on plasma cutting and a frequent speaker at key industry conferences. If you have a question you'd like Jim to answer please send it to askjim@hypertherm.com.
Get answers to more of your metal cutting questions at the Hypertherm Cutting Institute. |
