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bart2004
11-25-2005, 06:18 AM
i have not been too successful in welding tubing. either i burn holes in the interface or if i lower the heat, the weld is poor. tubing is standard .06.
any experiences appreciated.

i will be fabricating the complete exhaust from the exhaust manifold exit down.

MultiSmith
11-25-2005, 12:27 PM
What is the welder setup, What welder are you using, what is the size and type of wire being used, Flux core or Gas being used?

Example: I have a MillerMatic 175 and use gas mix of 25% co2 and 75% argon. My wire is size 23 2Lbs. spool of AWS ER70S-6 MIG Wire. #24 would work aswell if need be. Home depot carries Lincoln 25 AWS ER70S-6 which is an all around universal wire for most DIY folk. Depending on whether or not the tubing is galvinized or aluminized I may gently sand\grind slightly bevel the end being welded. Using the #23 wire I set my welder to 3/70 for tacking and 2/70 ish to fill in between tacks. I don't use flux wire indoors and its likely to burn through thinner metals.

I used 23 to fill in my dodge ram west coast mirror door holes when switching back to conventional mirrors and didn't even need to heat sink the back. I short I found that using GAS mix with 23 wire works best on thin metal 16-24 guage. where structural integrity isn't life or death.

dandimand
11-25-2005, 04:18 PM
you can do it with mig but i dont reccomend it . if you do do short little beads so as to not burn through make sure you have a tight fitup as any gaps are just begging for problems .

Desertwolf
11-26-2005, 03:29 AM
I built the complete exhaust on my '99 Ram using my MM210 with no problems.

I'm running Ar/Co2/O2 trimix with .030 70-s6 wire. I got good welds, no problem.

Coalsmoke
11-26-2005, 04:31 AM
It is definitely possible, just takes some set-up and practice. I routinely weld 16 gauge (which is pretty close to your .06), using .030 FC and no gas. Not saying go running out and buy FC, just that with practice, you should be able to do it with what you have to work with. Good luck:)

imported_frank865
11-26-2005, 05:46 AM
you can do it with mig but i dont reccomend it . if you do do short little beads so as to not burn through make sure you have a tight fitup as any gaps are just begging for problems .

Why do you recommend not using MIG?
The local muffler shops ALL use MIG, & I use MIG on exhaust work at least once a week! The only problem I ever have is old thin & rusty stuff.
I use a MM185 tap 2 or 3 .030 wire / co25 & wire speed about 55.

Blown S-10
11-26-2005, 06:22 AM
mig'n exhaust pipe is EASY.

Leons2003
11-26-2005, 08:10 AM
Why do you recommend not using MIG?
The local muffler shops ALL use MIG, & I use MIG on exhaust work at least once a week! The only problem I ever have is old thin & rusty stuff.
I use a MM185 tap 2 or 3 .030 wire / co25 & wire speed about 55.

I agree,Frank, my SIL uses this RX at his muffler shop as well as a small mirror to check the top of the pipe to check the pass. Only come-backers are folks needing other systems.
Good day all
L*S

dandimand
11-26-2005, 12:12 PM
Im assuming he was talking about building headers not exhaust . Im not sure the gauge of the header material i use but im sure its around 20 gauge maybe 18 at most . this is the mandrel bends you buy . most exhaust tubing i agree can be done with mig as it is thicker. and most muffler shops dont butt weld they have overlaps on tubing with flanging one end larger than the other slip fits etc... . what i have found is to maintain enough heat in the weld without getting cold laps is you can only do short sections or when you turn heat down you get highy crowned welds with cold laps on the restarts .but of .06" i dont see a problem its when you get into the smaller material like 20 gauge which is approx .036" you will have this problem.

imported_frank865
11-26-2005, 12:29 PM
Im assuming he was talking about building headers not exhaust . Im not sure the gauge of the header material i use but im sure its around 20 gauge maybe 18 at most . this is the mandrel bends you buy . most exhaust tubing i agree can be done with mig as it is thicker. and most muffler shops dont butt weld they have overlaps on tubing with flanging one end larger than the other slip fits etc... . what i have found is to maintain enough heat in the weld without getting cold laps is you can only do short sections or when you turn heat down you get highy crowned welds with cold laps on the restarts .but of .06" i dont see a problem its when you get into the smaller material like 20 gauge which is approx .036" you will have this problem.

His original question was...tubing is standard .06.
i will be fabricating the complete exhaust from the exhaust manifold exit down.

So I don't think he was talking about headers, how about it Bart2004?
Help us help you...Jump back in here anywhere! :D

90blackcrx
11-26-2005, 12:32 PM
Take your time
Weld 1/4 of the pipe and either stop for awhile and let the piece cool down, or lower the heat on the machine. Start on another piece of the pipe though, do not start on a bead that you already layed down.

imported_frank865
11-26-2005, 12:36 PM
Take your time
Weld 1/4 of the pipe and either stop for awhile and let the piece cool down, or lower the heat on the machine. Start on another piece of the pipe though, do start on a bead that you already layed down.

How's he gonna do both??? Start on another piece of the pipe
do start on a bead that you already layed down
Can't do both???:confused:

90blackcrx
11-26-2005, 12:43 PM
I ment don't , I was editing it and missed that part. It will be better in a second.

DDA52
11-26-2005, 03:33 PM
I do my truck exh all the time....with both FC and solid wire (.030 ). No troubles whatsoever. 18 and 20 gauge is a snap as well with .023 wire. I even did them with 3/32 6010's way back when.