Plazma problems

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What would cause a plazma cutter to make an angled cut when the torch is clamped 90 degrees to the cutting surface and a new tip, cover, etc. is installed?This problem has just started and can't seemed to be corrected.  Any suggestions?
Reply:What Thickness are you trying to cut, what type material, what model amperage of plasma cutter ??    These would help get you better answers.   However, ALL plasma cutters have an angles on the kerf/cut.  This increases as you get thicker on the material and closer to the units ability to cut.Steven
Reply:The material used is no more than 1/4" and the material is mild steel. I'm not sure about the make, because a friend of mine is having the problem, but I think the machine is a Torchmate or Thermodyne. He's had the setup for awhile and has done quite a bit of work with it, with no problems. This has just started.
Reply:Do you mean that you are getting a mitre in the cut (i.e., ----/  (cut)  /----, not ----|  (cut)  |----)?Bad tip and electrode is the first two things I'd check.  Once the tip starts to get worn, the direction of the plasma flow can go any whicha way.  You say that you put a new tip on, though.  Sooooo...maybe the swirl ring thingie inside...If it is not properly working, the plasma gas will not get evenly distributed and might cause immediate damage to the tips...but that's just a guess.I'd look carefully at the tips, specifically at the hole in it.  See if there are any irregularities at all.  If so, the gas flow is wrong.  Then it's a matter of figuring out what has caused the irregularity in the first place.  Normally, that just happens with wear, but it could be caused quickly by some other internal/mechanical problem with the torch.(added thoughts)First make sure you are getting plenty of air flow to the cutter.if you are, one thing that you might try that would avoid possibly ruining another tip is to:1) cut a piece of metal thick enough to see the direction of the mitre.2) turn the tip 180 degrees3) cut another piece and see if the mitre reverses direction.If it does, your tip is at least PART of the problem.  At that point I would take the gun apart and look for issues upstream (worn parts, obstructions to the plasma flow, etc.)Last edited by smithboy; 03-08-2006 at 04:11 PM.Smithboy...if it ain't broke, you ain't tryin'.
Reply:Smithboy, ......... Yes, a miter cut is exactly what it's doing. Everything has been changed. I suggested everything that I can think to solve the problem and I'm now drawing a blank as to what is causing this. Have worked with plasmas for years and never run up on this before.
Reply:A mitre cut is generally caused by a plasma flow problem of some sort at the gun.  What gun/equipment are you using?  Most plasma manufacturers have a parts breakdown on their website...along with a trouble shooting guide...A picture like that might help you to zero in on the problem.  If they dont, folks that sell replacement parts often have something that's close to a breakdown.If you turn the tip around 180 degrees and the miter cut remains the same, the problem is behind the tip (even though the tip is going to be a problem very quickly).  If turning it causes the mitre to change directions, the tip is At least part of the problem.  Even new tips can get bent or damaged in shipment.  If it appears to be behind the tip, I guess I would use the manual's parts breakdown as a guide and dissassemble the gun until all I had was an air hose and power cables, checking every part for the slightest sign of problems or misalignment.As an asside, I have heard of shorts in the gun causing problems, but I have never actually experienced anything like that myself.  Most of my plasma problems have come from obstructions in the tip, using tips WAY beyond service life, or bad air, i.e., oil and water contamination.As another asside, if it does turn out to be related to the tips, remember, a mitre doesnt matter on thin material...so, they are still useful.Last edited by smithboy; 03-08-2006 at 05:53 PM.Smithboy...if it ain't broke, you ain't tryin'.
Reply:Thanks, I'll give your information a try. Sure hope this works because it really starting to become a real problem. .......... Bill
Reply:++ on smithboy's comments.   ]One other thing.. is he draging the tip?Is he maintaining a proper distance from the work?  Holding high can cause the arc to wander.  Sorry if this next one sounds simplistic but gotta ask...Is he holding the torch that way?   You wouldn't believe how much time I have wasted before looking for an indepth cause only to find it be something silly and simple.Steven
Reply:Steve, ........... He's got it setup on a computer and table. It's all automatic. I"ve always cut everything manually, so being that it's computer driven I figured there is something that I might have overlooked, as to the source of the problem.I'm going to be away for a few days, working on a job out of town, so as soon as I get back I'll reply to anymore suggestions that anyone might have concerning this problem. .............. Thanks