I am going to be tig welding a lot of .035 4130 tubing. A lot of the "big guns" are using either ER70-S2 or ER312. Both are getting very good results. What's your take?
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heres my take...
For that thickness, ER70-s2 will work fine.
the er312 will cost a lot more and might actually look better but is not necessary.
ER70 tig welding rod is pretty cheap..like only around 3 bucks a pound.
I think you will pay as much as 20 bucks a pound for the 312. Its handy to have around, just not necessary. Also, if field repairs are a possibility after the fact, its better to weld over the ER70S2 welds
thanks for posting,
jody