Got my kegs back.. what do you think

[aekdbbop]

btb.. i paid 180 for the total job (9 welds, 3 tops).. so who knows what kind of deal i got.//

 

[Yuri_Rage]

What some guys do for welding stainless is to use a MIG (Metal Inert Gas) (wire-feed or 'squirt welders', one handed welding) welder and a spool of stainless wire, however they are not equipped to use the inert gas to weld. Some MIG's like those for home use, do not facilitate a shielding bottle gas. You must specify that the equipment you want is TIG with inert gas. MIG, with gas is acceptable.

Backgassing is a poor term. The weld should be made using inert gas on BOTH sides of the weld.

Wirefeed welding without inert gas shielding is done with flux-cored wire. That is not MIG (Metal Inert Gas) welding, it is flux core welding, or FCAW (Flux Core Arc Welding). FCAW IS UNACCEPTABLE for most stainless applications.

I would highly recommend finding a skilled TIG welder for your brew equipment. MIG, though a simpler process, is harder to control, even when properly shielded, and it usually results in a much "taller" weld bead.

FYI, more "modern" terms for MIG and TIG are GMAW (Gas Metal Arc Welding) and GTAW (Gas Tungsten Arc Welding), respectively. Most welders haven't adopted those terms, though welding texts use them quite often.

"Back gas purging" is the full and correct term for the process your shop should be using.

 

[pickles]

yuri any thoughts on using co2 for my back gas purging or does it have to be argon?

 

[kladue]

Co2 works for copper brazing but not as a backup purge for stainless welding, weld sugars and discolors when Co2 is used.

 

[pickles]

great info thanks kladue

 

[balto charlie]

If I were to go to a welding shop for work on my stainless brew equipment, I would ask the following questions:

Can you TIG weld stainless?
How much experience do you have with it?
Can you back-gas all of the welds on this job?
How much will it cost...and will a few homebrews get me a discount?

If you get anything less than a positive, knowledgeable answer to any of these questions, consider using another shop, or using weldless fittings.

Thanks, Now I can act smarter than I really am

 

[beermetoo]

Should have been tig welded and burn through could have been non existant... Back gassing if possible is totally not necessary... The only way to have a perfect weld would be to weld from the inside, which would be tricky but possible...

Use a angle grinder with a layered type sand paper disc to clean it up... As the sand paper wears off a new layer is behind it-- it will clean those welds nicely without gouging or removing too much metal.

 

[beermetoo]

something like this...
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200309205_200309205

Also those are not poor welds-- If the welder used a tig machine, he was a little hot, but structually they are fine... Just clean them up with the a wheel like above and you love 'em.

 

[beermetoo]

yuri any thoughts on using co2 for my back gas purging or does it have to be argon?

no co2 when tig welding...

 

[pickles]

i used argon and mig welder