plasma cutter help

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Can any one explain the differance between large(long) and small(short) tips.
Reply:I believe the long tips (electrodes) are simply to allow a better view of the cut by the operator with handheld torches and to allow getting into tighter spots.  However, Jim Colt from Hypertherm http://weldingweb.com/vbb/showthread.php?t=29041 can certainly answer your question if I'm incorrect.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Longevity should be able to answer this but....the torch you have is likely a trafimet style torch with two or three possible combinations of consumables.  The longer ones are for cutting in corners and inside holes.  Most of the longer nozzles have small little tabs built into the  nozzle to serve as stand off on the nozzle so that you won't burn it out from dragging.  But they do not work as well as the short ones because slag is constantly sticking to the little tabs.    Don't attempt to drag cut more than 30 amps either.  Most machines that are equipped for drag cutting are under 30 amps.  Use the wire guide, or add on roller guide to hold the tip at about 1/8" or slightly more distance from the surface over 30 amps.  You will increase your electrode life this way.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:The difference between long and short consumables with a plasma torch requires more than one answer....and can be brand specific as the design of different torches and power supplies will react differently to different consumable part designs.First....some plasma torches are shielded....this means that there is another part called a shield....that surrounds and covers and electrically isolates the nozzle (some call the nozzle a "tip")......some shielded torch designs are more pointed.....meaning the front of the torch can get into tight spots, and has good visibility for the operator. With a shielded torch you can drag cut at any amperage level. A Hypertherm Powermax45 has shielded consumables that are extended....with good visibility, and can be dragged on the plate. There are many plasma systems that have unshielded consumables.....and generally when you drag cut with unshielded consumables at amperages over 30 Amps....a phenomenon called "double arcing" ocurrs.....this is an arc that jumps fron the electrode to the inside of the nozzle, then from the outside of the nozzle to the plate. Drag cutting with a non shielded torch causes "stiction"....the torch tends to stick to the plate which makes the cuts kind of ugly, and this double arc causes more rapid wear on the nozzle in the form of nozzle orifice erosion...which affects cut quality. Some manufacturers claim that their systems can drag cut with unshielded consumables to 60 Amps.....however if you compare life of their consumables with another torch with shielded consumables drag cutting...the shielded system will provide 2 to 3 times the nozzle life at 60 Amps. At 30 Amps and below, double arcing still occurs, but causes less damage to the nozzle orifice. There is nothing magical that a plasma torch manufacturer can do to eliminate double arcing from the nozzle to the plate in a non shielded torch.....laws of physics take over!Some torches have both shielded and non shielded consumables available. Bottom line.....for best cut quality and consumable life at amperage over 30.....use shielded consumable parts. For best visibility and to get into tight locations.....either use a shielded torch with a pointed front end, or switch to the longer, non shilded consumables. With non shielded parts at over 30 Amps.....try to hold a standoff of 1/16" to 1/8" for better consumable life.Jim ColtLast edited by jimcolt; 01-08-2010 at 07:52 AM.
Reply:Thank you everyone that is what I needed a very detailed explaination of the answer.You guys have great information.