Tonight we used the plasma cutter.

[pgmrdan]

At one point in tonight's autobody class we took turns cutting up some scrap fenders with a plasma cutter. Those things are awesome but I didn't get any explanation about how they work.

Can someone explain how plasma cutters work?

Thanks,
Dan

[CCWKen]

The plasma field melts the metal and the air blows it away. Kind of like an O/A cutting torch but the plasma cutter doesn't oxidize or burn the metal. That's why it can be used on any conductive material.

Here's what Wisegeek says about it:

<font face="Verdana, Arial" size="2">A plasma cutter is a relatively easy-to-use tool to cut steel and other electrically-conductive metals. These cutters work by using a high-voltage electrical arc and a compressed gas, usually air. An electrical arc generated by an internal electrode ionizes gas passing through a nozzle, creating a concentrated arc of plasma at the cutter’s tip. The arc’s contact with the working surface makes a high heat circuit which melts a section less than 1/16” (1.6mm) wide. The force of the plasma flow then literally blows out the molten area on the work piece, creating a fairly clean cut with little or no slag. The plasma arc travels through the nozzle at a speed of up to 20,000 feet per second, and at temperatures as high as 30,000 degrees Fahrenheit (16,600 Celsius)!</font>

[This message has been edited by CCWKen (edited 01-25-2006).]

[Dawai]

First thing I did when I got mine? Write my name.



Nothing else will cut the stainless like a hot knife in butter. You do have to remember to pull the plastic off it.

[Herm Williams]

Hello
It will cut cast like butter also.
re

[3 Phase Lightbulb]

I made the mistake of cutting a 3/16" x 2" FLAT about 2 inches above my shop's concrete floor and the somehow the plasma blow through made a 1/4" deep divot in my concrete floor.

[pkastagehand]

I don't know if I can explain it but I can tell you what the books say.

One thing they say is don't cut directly on concrete!

They work by sending an electric arc through a gas that is passing through a constricted opening. (gas: shop air is common, nitrogen, argon and oxygen, etc.) The arc (and pressure I assume) raise the temperature of the gas to the point that it enters a 4th state of matter which science types call plasma. The electrical conductivity of the plasma causes the arc to be carried to the work. You get a venturi effect at the nozzle which causes the air/plasma to go through at high speed. This highspeed super-heated stream puddles and blows out the metal.

[This message has been edited by pkastagehand (edited 01-26-2006).]

[YankeeMetallic]

I bought a Hypertherm Powermax 1000 about a year ago to do a big job making support brackets for a deck overlooking a canyon.
It is unbelievable how little time it takes to make a cut, and it leaves very little slag that can be banged off in one stroke on the welding table. It does not heat up the surrounding area so you can cut very thin metal quickly without warpage. Only a pro could match the results with a O/A torch. It just uses my 220 V outlet and my air compressor at 100 psi. Mine claims to cut 1 1/8" solid. I have only cut up to 3/4" so far.
I made a little cart for it because the cheesy "wheel kit" was made out of plastic.
I am currently making circle/arc templates for cutting specific arcs.
It was spendy though at about $2200.

[3 Phase Lightbulb]

<font face="Verdana, Arial" size="2">Originally posted by YankeeMetallic:
I bought a Hypertherm Powermax 1000 about a year ago to do a big job making support brackets for a deck overlooking a canyon.
It is unbelievable how little time it takes to make a cut, and it leaves very little slag that can be banged off in one stroke on the welding table. It does not heat up the surrounding area so you can cut very thin metal quickly without warpage. Only a pro could match the results with a O/A torch. It just uses my 220 V outlet and my air compressor at 100 psi. Mine claims to cut 1 1/8" solid. I have only cut up to 3/4" so far.
I made a little cart for it because the cheesy "wheel kit" was made out of plastic.
I am currently making circle/arc templates for cutting specific arcs.
It was spendy though at about $2200.</font>

I got my Powermax 1000 about 2 months ago. I haven't used it much yet. Do you have any suggestions/tips/tricks for this specific model? Should I keep using the factory installed drag tip? Have you tried any of the fine-cut optimized tips for thin material, etc?

-Adrian

[cam m]

Adrian you lucky dog. Drag tip? That's an option I wish I had on my 380. From what I gather from your video and others it does give easier cutting if somewhat bulker and reduced visibility of the actual cut. FWIW, accidental contact with the work has shortened the life of the tip on my unit.
Cam

[This message has been edited by cam m (edited 01-26-2006).]

[rmancini]

This may be of interest for cutting circles & arcs.
I have a sketch available.

http://i40.photobucket.com/albums/e2...ini/Photo5.jpg

Rich