I mentioned Plasma Cutter to someone and they asked why you would cut plasma.

I finally decided that my skill level with an oxy-acetylene torch was not improving and was abysmally poor and likely to remain substandard. I resort to various schemes to avoid having to use the torch since the results are so humbling yet I have need to cut metal in ways that don't lend themselves to abrasive cut off disks, chop saws etc.

SO!!! I took the plunge and bought a plasma cutter. It has a max amperage of 27 amps and is sized for rapidly and smoothly cuting 1/4 inch steel. It will cut 3/8 pretty well and will "sever" 3/4 steel but the cut is NOT smooth or fast. I have been cutting mostly 3/16 with it and the cuts are fast and neat. I have cut 40 circles out of 3/16 and it is easy to use and does a good job, even with me using it.

I made a couple circle templates out of 3/4 inch MDF, each an inch in diameter (ID) larger than the circle I wanted to cut to allow for the 1/2 inch distance from the plasma jet to the side of the torch. The templates got singed a bit but are still servicible after each was used to do more than 20 circles. The circles were roughly 1 1/8 inch and 2 1/8 inches. I surprised myself at how neatly I could cut the 3/16 steel.

I cut off some 3/4 round bar and that was a tad messy requiring significant dressing with a grinder. That is a job better left to the abrasive chop saw. Also not having a jig for cutting pipe with the plasma I used the saw to cut up a length of 1 inch pipe into 3 inch lengths.

I don't have the optimal eye protection. My auto darkening welding helmet only turns down to about a shade # 7 and acording to the ANSI specs I need a shade # 4 or 5 depending on current setting and how shielded I am by the configuration of the workpiece and the torch. I turned the auto darkening off and just use the built in filter density but I think it is still a tad too dark. It is hard to see and follow the chalk marks of my soapstone.

What seems to work the best for me since I have trouble seeing the soapstone markings is to use a guide of some kind. For cuting a straight line I clamp a board 1/2 inch from the cut line and let the torch follow the board for a neat straight cut. Another difficulty is trying to hold the torch 1/16 inch above the surface of the steel being cut. I end up making a lot of tip to workpiece contact which at the lower current settings won't matter much but at the highest settings will eat on the "consumables" at an uneconomical rate.

Any other plasma users out there who can share their experience regarding shade# and such?

After using the plasma for a little while I can safely say I don't plan on spending much time trying oxy-acetylene anymore. I will send my tanks back to the welding supply house. I will keep my small bottles for just in case, brazing, silver soldering, or whatever but I can't think of anything I'd need the biguns for any more. (Don't say PREHEAT as I have carbon arc accessory for my Lincoln "Tombstone" which will preheat OK.

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]