learning to weld stainless tube

sarabande

sarabande

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how easy is it to learn to weld SS tube please ? And what is the best kit ?


I can gas weld reasonably thick metal up and down fairly neatly, but have never tried stainless.


20 hours practice to achieve a decent standard ? The objective is to make a gantry for a friend's Cutlass in (?) 1 inch tube.


Best to try it on my own, or should I exchange a few beer tokens to the young lad in the local garage whose work is pretty neat.
 
If you have a tig welder and use pure argon with 316 filler rods, it's fairly easy. If you don't have the necessary gear it would be better to part with the beer tokens.
 
I did a TIG course at the local tech , took quite a while to get proficient but I never managed tube. That was a whole new game. By the time you've got the gear rented, bought the rods and argon and the wasted a whole lot of tube practising it really is cheaper to pay someone. A lot less fun but cheaper
 
I have a TIG set on board and argon bottle , do most of my own stuff biggest problem is getting a good finish , the less the heat and the less you feed in the better the finish , but you still need to spend time cleaning and planishing after

It's very similar to oxy acetalyne techniques I found.
 
If you make the joins very tight fitting you can get away without filler rod. Use pulse and dont forget to back purge, that is fill the tubes with argon.
 
I both stick weld and tig weld stainless and if you are using thin wall tube you must keep the heat down at any point by moving the arc point quite quickly and do not dwell at any point otherwise you will blow a hole and then its almost impossible to fill the hole. Also as said the joint must be close fitting else the above will happen alot.
 
I have been gas welding for many years and can make a reasonably good looking weld with it. I have done a fair bit of stick welding, making trailers and cradles. I acquired a TIG set and can manage to join thick stainless steel plate but thin tube has almost defeated me. I can stick it together but the appearance is mostly rubbish. I am told that the amount spent on a TIG set is in direct proportion to the quality of the finished weld. Son Owen works with professional TIG welders whose work is incredibly good, their sets are priced in four figures.
 
When we bought a TIG welder from BOC part of the deal was they sent a technician round to give us a couple of hours of one to one tuition:encouragement:
 
I would go down the MIG route 316L filler wire and the right shield gas. Different gas for stainless.

TIG is the best method but it requires a very high skill level to weld thin tube even welders who use TIG on a daily basis will sometimes struggle with thin tube.. So MIG is much better for the less experienced. The welds won't be as pretty but they will do the job.
 
TQA said:
I would go down the MIG route 316L filler wire and the right shield gas. Different gas for stainless.

TIG is the best method but it requires a very high skill level to weld thin tube even welders who use TIG on a daily basis will sometimes struggle with thin tube.. So MIG is much better for the less experienced. The welds won't be as pretty but they will do the job.
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I agree entirely. Tig can be very frustrating.
 
Don't expect to be anywhere near competent with TIG until you've been at it for at least a year. I make reasonable quality pulpits using 1 inch tube but it has been a long hard road. MIG is far easier so I'm told but still more complex than basic arc.
 
Don't rule out arc/MMA either. I'm a reasonable 'hobby' welder with MMA, MIG and TIG gear and much prefer MMA for stainless work. Use quality electrodes (Nicrex Murex E316L for example, even on 304) and a quality inverter machine with adjustable hot start current/time that allows you to use the minimum amperage but with a substantial boost for starting the arc easily and accurately. Cutting the rods into thirds is good for precision too.
 
Best would be to make all the bits, get the joint fits right, then find someone to weld it. I do Arc, Mig & Tig on stainless and would not reccomend Arc on thin stuff or trying to learn Tig for one job, apart from the cost of the kit and gas. As said, Mig will do it, tidyness dépends on how good you get quickly.
Look at the mig-welding.co.uk forum and read the tutorials. They deal with all three types of welding and you can form a better opinion of your chances after reading them.
 
My view would be that you need quite a large project to justify the investment in terms of time materials and equipment required to achieve a high standard. That said, if you want to go with TIG, invest in a HF set, pure argon for shielding gas, thoriated tungstons, 316L x 1mm filler, 309L if you're welding stainless to mild steel. Grind the tungstons to a fine point and regrind if the tungston becomes contaminated. Keep the gap to 1mm to 2mm. Keep the joints tight and well fitted. You can butt weld a well fitting joint without filler and this is a good way to practice technique before adding filler. Distortion is a nightmare so you have to learn to work with it or it'll break you. If you're welding a tee joint, you'll need to use a strong back and a couple of g clamps and a spacer positioned such that you pull the straight section of tube a couple of mm away from the tube that you're welding to it. That way when you release the g clamps after welding, the distortion will have pulled the tube straight again. Takes practise to get a feel of how much of a curve to pull into the tube prior to welding.
 
I wasn't talking about tig, I quoted about mig. The OP said he can gas weld to a reasonable standard, so he should be able to get OK results with a *relatively* small amount of practice. Agreed mig is more complicated than stick in terms of getting the setting right but once you've got that its easier to get neater welds IMHO.
 
thanks for all the advice and experience, everyone.

Having spent ten minutes watching the local garage wizard play with complicated welding machines, rare gas bottles, and 'sticks' of various sorts, I recognise that my ambition has limitations. It's an art as much as a science.


I shall measure up very very carefully and ask the professionals to put together a gantry later this year.


thanks again.
 
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