Harbor Freight Tig for pipe root?

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Guys, I was wondering your thoughts on possibly using a harbor freight tig welder (130A) for tig welding root passes to practice my pipe welds? Would something like this have enough current for say 6" diam pipe with a 1/16 face? Something like this would be great if it would work. I dont have access to a bigger high dollar machine right now, but want to practice with pipe. I also have an old forney AC 220 welder that ive been using. I'll be practicing with 6011 root, 7018 cap, and the harbor freight unit for root as well if its powerful enough.Thanks for you help!
Reply:BTW, on another forum, a man has claimed to weld  4"x2"x3/16" tubing running about 80% with no problems. The rig itself has actually gotten some really good reviewsIt is a lift start, no pedal control, but this is what I want to use, because there isnt always a foot pedal in the field.
Reply:I have that welder and for the money it is a good machine.
Reply:partagas, do you think its enough for this task?
Reply:Originally Posted by njmm313Guys, I was wondering your thoughts on possibly using a harbor freight tig welder (130A) for tig welding root passes to practice my pipe welds? Would something like this have enough current for say 6" diam pipe with a 1/16 face? Something like this would be great if it would work. I dont have access to a bigger high dollar machine right now, but want to practice with pipe. I also have an old forney AC 220 welder that ive been using. I'll be practicing with 6011 root, 7018 cap, and the harbor freight unit for root as well if its powerful enough.Thanks for you help!
Reply:Delweds you have it on the head.  The root pass will be fine, the problem is if you have to run a hot pass ( tig) with it.  The duty cycle on 6in will drive you nuts.  You will need half an hour or more just to do that.  You should be able to do the whole pipe with that system.  Just have to stop after every rod to let it cool down.  But that also gives you extra time to clean your weld.
Reply:thanks a lot guys. I did forget about the hot pass. I was thinking 7018 after the root, but i think you are right. The duty cycle for this model is 35% @ 130 amps. Can you guys elaborate on what this means in terms of how much time I can weld, vs how much time she has to cool down? Thanks
Reply:another quick question.My whole goal here is to practice my pipe welds, and eventually take a cert test. I graduated tech school about 3 years ago, and havent done any pipe welding since then.If I were to go with thinner pipe, something that would be better suited to weld with the harbor freight machine, how difficult of a transition do you think it would be welding on thicker pipe?example, in tech, we were only taught GTAW on thin material, because it was said that if you can control heat and penetration on thin material, thicker was easier.Does this still hold true with pipe?
Reply:35%@130amps duty cycle means you should be able to weld 3 minutes and 30 seconds continuously and then let the machine cool down for 6 minutes and 30 seconds.  The duty cycle concept is based on how much of a 10 minute period the machine can run.  If you're working at less than the max rated amperage, the duty cycle goes up.I don't think it's a strict linear relationship, but given the duty cycle you mentioned, you should be able to weld about 7 minutes at 65 amps, with about 3 minutes of cool down time. Originally Posted by njmm313thanks a lot guys. I did forget about the hot pass. I was thinking 7018 after the root, but i think you are right. The duty cycle for this model is 35% @ 130 amps. Can you guys elaborate on what this means in terms of how much time I can weld, vs how much time she has to cool down? Thanks
Reply:In general, I'd agree with what you were taught.  Thicker wall pipe is just more passes.  It should take more heat and be less prone to overheating; all other things being equal.  IF you can TIG or stick weld 2" sched 40, you should have no troubles running either TIG or stick on larger or thicker walled pipe.  Large diameter is more welding but everything is more gradual and should be easier.  Thicker wall just means more passes... Originally Posted by njmm313another quick question.My whole goal here is to practice my pipe welds, and eventually take a cert test. I graduated tech school about 3 years ago, and havent done any pipe welding since then.If I were to go with thinner pipe, something that would be better suited to weld with the harbor freight machine, how difficult of a transition do you think it would be welding on thicker pipe?example, in tech, we were only taught GTAW on thin material, because it was said that if you can control heat and penetration on thin material, thicker was easier.Does this still hold true with pipe?
Reply:thanks A_DAB. I did find a conversion chart, and its about 6 1/2 minutes rest for 3-3 1/2 welding like you're saying. It would be nice to just practice on bigger thicker pipe though because its much less prep work I would have to do for how much weld time id get out of each pipe coupon.Do you by chance know the standard thickness and size of pipe that you would use for a 6g cert?
Reply:It all depends.    Whatever size pipe you test on covers a range of diameters and wall thicknesses in most welding Codes.  So, for example, a test on 2" pipe sch 160(.5" wall thickness), covers you welding on something like 1" O.D. up to 4" O.D., and wall thickness ranging from .25" up to 1".  Those numbers are all just guesses...make sure you check the code you're testing to and find out what's covered.The certs are also by position.  For AWS, for example, you can certify on plate in flat, horizontal, vertical and overhead.  Fillet and Groove joint types.  You can also certify on Pipe, in 6G position(45 degree angle), which covers you on pipe AND plate in all positions. Not sure if ASME or API have the same kind of blanket inclusions for pipe in 6G.Basicly, you'll get a cert, or multiple certs to cover whatever you're doing on the job. The cert is good so long as you keep welding at least once every 6 months.( or 3 months, or 12 months, or whatever the code regs say)If you're getting a certification on your own, do some research before spending your money.  Otherwise, let your future employers pay for and keep track of your certifications.  They're not transferable, and they're a pain in the butt to keep the paperwork up to date on your own...  Originally Posted by njmm313thanks A_DAB. I did find a conversion chart, and its about 6 1/2 minutes rest for 3-3 1/2 welding like you're saying. It would be nice to just practice on bigger thicker pipe though because its much less prep work I would have to do for how much weld time id get out of each pipe coupon.Do you by chance know the standard thickness and size of pipe that you would use for a 6g cert?
Reply:Thanks A DABDamnit, I need to find some kind of fitter apprenticeship!
Reply:Originally Posted by njmm313if you can control heat and penetration on thin material, thicker was easier.Does this still hold true with pipe?
Reply:I agree 100% with everything a dab told you.  Look into the UA for a fitter apprenticeship.  Or If you want to get a job as a helper look at the "hotsheets".  I know some companies will give you a helper job with zero experience in any trade, so look around.  Maybe try Industrial Projects Report, or Industrial Tradesmen, both good options for finding work.