What Señor Vega said. Aluminum takes more juice to plasma cut than steel does, due in part, I think, to its tendency to immediately form aluminum oxides, which melt at a waaaay higher temp than aluminum. Also, the aluminum has a much higher rate of thermal conductivity than steel, so it dissipates the cutting heat quicker.
For cutting aluminum, you want to have the stuff as clean as possible. De-grease with TSP or solvent, then rinse and dry. Scuff lightly with a Scotchbriteâ„¢ pad to remove oxides, then cut promptly. It will still take about 50% more juice than a comparable thickness of mild steel. So, if your plasma rig can conveniently and cleanly cut 3/8" steel, you can get the same results with aluminum up to about 1/4", possibly 5/16" on some alloys.
For stuff where you need a pretty precise cut, and can afford the time, you can cut 3/16" 6061-T6 reasonable well with a jig saw or a router. For straight cuts, I usually just use a Skilsaw or a table saw and high tooth-count carbide tipped blade, one with a triple-chip tooth grind.
When cutting sheet metal or plastic with a jig saw, I do it on top of a sheet of 3" thick hard styrofoam insulating board. The blue stuff, not the wimpy white beadboard crap. That way, the stock doesn't flop around and invite blade breakage and nasty language. The same sheet of styrofoam can be used hundreds of times; as long as it is thicker than the maximum penetration of your blade, it stays together.
What Señor Vega said.
What Señor Vega said. Aluminum takes more juice to plasma cut than steel does, due in part, I think, to its tendency to immediately form aluminum oxides, which melt at a waaaay higher temp than aluminum. Also, the aluminum has a much higher rate of thermal conductivity than steel, so it dissipates the cutting heat quicker.
For cutting aluminum, you want to have the stuff as clean as possible. De-grease with TSP or solvent, then rinse and dry. Scuff lightly with a Scotchbriteâ„¢ pad to remove oxides, then cut promptly. It will still take about 50% more juice than a comparable thickness of mild steel. So, if your plasma rig can conveniently and cleanly cut 3/8" steel, you can get the same results with aluminum up to about 1/4", possibly 5/16" on some alloys.
For stuff where you need a pretty precise cut, and can afford the time, you can cut 3/16" 6061-T6 reasonable well with a jig saw or a router. For straight cuts, I usually just use a Skilsaw or a table saw and high tooth-count carbide tipped blade, one with a triple-chip tooth grind.
When cutting sheet metal or plastic with a jig saw, I do it on top of a sheet of 3" thick hard styrofoam insulating board. The blue stuff, not the wimpy white beadboard crap. That way, the stock doesn't flop around and invite blade breakage and nasty language. The same sheet of styrofoam can be used hundreds of times; as long as it is thicker than the maximum penetration of your blade, it stays together.