OT? Plastic welding

The plastic gas tank on my lawn mower is cracked and leaking. I'm reluctant to spend almost $50 for a new tank when I can spend less than half that on this.
http://www.harborfreight.com/welding/plastic-welders/plastic-welding-kit-41592.html
My questions: is this tool a POS or will it do the job? Does anyone have any first hand experience with it or it's kin? Is it just wishful thinking that the tank can be fixed well enough to withstand that high vibration environment? Any other suggestions? Art
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http://www.harborfreight.com/welding/plastic-welders/plastic-welding-kit-41592.html
It likely will do the job. Plastic welding is a little unlike welding metals in that you don't really create molten puddles. Instead, you raise the temperature to near melting, and it fuses to the filler. The one problem you may have to address is if you need nitrogen to weld the particular material in question. Hot air, alone, won't work for all plastic types.
While you may enjoy success welding the gas tank, give some serious thought to the consequences should the weld fail during operation. If there's the slightest chance you could set anything on fire (like your wife or kids), lose the idea of welding and buy a new tank. There are times when the price of a new item is a bargain. This might be one of them.
Harold
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They do work and I can not recall one that was defective 'out of the box'. The slightly more expensive model is better / more versatile. http://www.harborfreight.com/welding/plastic-welders/plastic-welding-kit-with-adjustable-temperature-96464.html It works about as well as a *very* expensive Sealy (sp?) I remember using at another job 30 years ago.
Any of them will burn out the heating element in just a few seconds if plugged in with no air flow. Which is why there will never be a Sealy at my current job... I do save the gage and regulator off all the burnt out ones, occasionally get to be a hero when someone manages to break that end.
Not as pretty of repair, but a plain old pencil type soldering iron will work on polyethylene for sure and possibly other plastics. Polyethylene is very forgiving probably the easiest to repair. You can cut strips out of a milk jug to use as filler.
--
William

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Artemus wrote:

http://www.harborfreight.com/welding/plastic-welders/plastic-welding-kit-41592.html
WELLLL! I bought one a few years ago to repair a garbage "can". and the problem is the air blows all the melted plastic away so it never has a chance to to the "welding" as it should. No matter how the air flow is adjusted.:-( ...lew...
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On Sat, 26 Jun 2010 07:30:55 -0600, Lewis Hartswick

Artie, I used some epoxy ribbon and it sealed my Murray mower tank cracks for over a year. It started leaking a bit again after that, so I stopped filling it all the way up. I see only a drip or two now, and I now have a riding mower for most of the work. I haven't removed the tank to see where it cracked, but I'll bet it is another crack in the tank itself. It's 8 years old now.

Try lifting the working end OFF the work next time, lew. ;)
-- The most powerful factors in the world are clear ideas in the minds of energetic men of good will. -- J. Arthur Thomson
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There are some good examples of plastic welding on video. Here are two: Done with a modified soldering iron:
http://www.youtube.com/watch?v=NuA6d49Z7Rc&feature=related
With a professional hot air tool (Mission Impossible theme song):
http://www.youtube.com/watch?v=I2pQKPxZMd0

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Denis G. wrote:

NOW! There is a fine looking piece of equipment. Of course the operator has had a bit of experience. :-) ...lew...
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Yes and he knows the materials he's dealing with, etc. Still nice to see a pro at work. The amateur with the modified soldering iron was equally impressive in my mind. When you look at the comments, the plastic wheelchair wheel that he repaired stood up to some extensive tests.
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The Achilles heel of plastic welding is the filler. You can buy filler easy enough, but matching it to your job is very iffy. I.e., it's almost impossible to know just what the material that you're trying to weld is. In a fix-it situation. Welding up known stock would not be a problem, but most of us would be using it to fix things. Like a gas tank.
Bob
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