Welding Chromoly Tubing

[Justin]

I was told that CM tubing for racecars can not be Mig welded, why is this?

Also, I have a Miller Econo TIG welder and am not so versed in TIG, if I am TIG welding CM tubing of .058 and .063 wall, what is the best Electrode, welding filler rod and machine settings to accomplish this welding?

Thanks,

Justin

[arcdawg]

i would recomend using 2% thor............an er-70 filler rod..........but as far as machine settings go.......well someone else will chime in.........

also dont for get about post heat..............

dawg

[ASKANDY]

There's a bunch of stuff on chrome moly on the forum. Do a search for chrome moly or 4130 and you'll have plenty to read.

Also, if you are not that skilled at tig welding, you will need to practice 'cause the chrome moly is very heat sensative and if you over heat it it will crack. Low arc lengths and tight fit ups. Use the ER 70S-2 or ER80SD-2 filler and 1/16 thoriated tunsten.

Andy