[Stagger]

Hello guys. I am new to the forum, but have watched Jody's vids forever. I have a question.I have to weld 1-3/8 chrome moly square bar to a piece of 3/8" plate. They dont want to take the time to tig anything, so it will be mig. I always weld chrome moly with tig and dont get it to hot. I have been welding for 23 years, but have never mig welded chrome moly. Just looking on ideas as to what gas, wire i need. I had a buddy to say use tri mix and 308 ss wire, and another say to use regular wire and 90 /10 or 72 /25/ Just wondering what you guys think is the best procedure. I appreciate any advice.


Tommy.

[Otto Nobedder]

Welcome, Tommy,

Is the 3/8" plate also 4130?

Apparently, they don't give a damn, or there'd be a procedure. I'm "for" the tri-mix gas, 90% he, 7.5% ar, 2.5% co2.

E80s-2 is my first choice for wire.

309Lsi is my second choice.

Good luck...

Steve S

[Alexa]

Hello guys. I am new to the forum, but have watched Jody's vids forever. I have a question.I have to weld 1-3/8 chrome moly square bar to a piece of 3/8" plate. They dont want to take the time to tig anything, so it will be mig. I always weld chrome moly with tig and dont get it to hot. I have been welding for 23 years, but have never mig welded chrome moly. Just looking on ideas as to what gas, wire i need. I had a buddy to say use tri mix and 308 ss wire, and another say to use regular wire and 90 /10 or 72 /25/ Just wondering what you guys think is the best procedure. I appreciate any advice.


Tommy.

=====

Stagger.

1 3/8" thick chrome moly bar to 3/8" thick plate (alloy ??)

Which chrome moly alloy is that 1 3/8" thick bar?
What alloy is the 3/8" thick plate?

The thicker bar will draw heat from the weld faster than the thinner plate.
The different chrome moly alloys (4130, 4140, etc.)have different tendencies to harden upon cooling.
You may want to preheat the joint, concentrating on the bar, to reduce the amount of hardening in the weld.

Tanks.
Alexa

[awill4wd]

Stagger, just use LW1 ER70 S-6 standard Mig welding wire and whatever gas you normally use for Mig welding steel and you will be fine.
We do lots of Tig welding on 4130 and we only use ER70 range wires, we've never gone up to the ER80 range as the ER70 wires give a bit more ductility for our applications.
Regards Andrew from Oz.

[Stagger]

Thanks alot for the info guys/girls.I used ER70 s-6 and 90/10 gas like awill4wd said, and it turned out great. The reason i went this way is because i had the gas and wire. I really appreciate the info .

Thanks alot.


Tommy.