plastic welder 5 minutes life

[wrench]

      Any one know if Argon flowing over a heating element will reduce its life?
   I went trough 2 plastic welder in one day (trying to repair a crack in a poly tank)
  I hook it to an Argon tank with a flow meter ( for ease of adjusting temp & avoid oxidation) .
     PLS where did I mess up?  Harbor freight welder, Argon, too tin or ??
   The tank is a drinking water tank in a travel trailer not more then 1/8" thick.
   When I heat it enough(using hot air gun(like hair dryer)) it become transparent(clear) When cold it's white. OR it's something else?
       Any pointerssssssssss
      thankssss   wrench

[boogiethecat]

My guess is that because of argon's low heat conductivity relative to air, the heating elements inside your welder have to get LOTS hotter than they would if you were using air, to make the argon coming out the nozzle as hot as it needs to be to melt the plastic.  Probably as you've seen, hot enough to burn the elements out. 
Harbor freight tools are kinda designed "to the edge" of failure anyway, and weren't designed for gasses other than air.
Try it with simple compressed air- everyone else uses the stuff and it works fine...

[Ray D]

I always use nitrogen for plastics welding, argon probably does not remove heat as well as nitrogen, but I don't think that is you're problem.  I don't think you have enough gas flow, it takes quite a bit to perform right.  Just think twice about air, I have never been able to get a good weld with air compressor, it takes very, very little moisture to make welding life hell.  Nitrogen will make you're plastic welding life real easy, but you do need good air flow.  Oh, on the harbor freight welder, it is the same one that sells for $130.00, even the tips fit, I have used on for about a year now with no problem.

Ray D

[wrench]

      Ray
"on the harbor freight welder, it is the same one that sells for $130.00, even the tips fit, I have used on for about a year now with no problem"
  It's the one at $30.00  #41592,
   I will try to get an other one just to keep on the shelf!!  The Argon is the problem, either flow or heat transmission or both. I used a flow meter & it let flow just a bit of Argon for tig welding.
        THANKSSSSS  for the help      wrench
   

[Ray D]

I checked "da book" and it said you need approx. 6 psi t0 weld and prolong the life of the element.  Turn the  air on before you turn the element on and then let it cool down after.  I have the manual that came with mine from Seelye, Inc.  If you want, I could turn it into a pdf. and email it to you.

Ray D

[TomC]

I have welded my tanks with a simple propane torch.  It worked well-why do you need the fancy welding equipment when a propane torch with plastic feed rod will work?  Good Luck, TomC