welding exhaust pipe

[sparky123]

i am welding some exhaust pipe for my truck this weeked. i was wondering if i should just but them togetherand weld away with my mm135 or put a ring inside and then weld. thanks in advance from a novice.

[Sberry]

I usually dont put anything in them, I make the fitup nice and tight, weld it up

[Bendaman]

This also might help. To get the the tubing to fit nice end to end, I have
used hose clamps with slots cut in them. Tack the tubing thru the slots take
off the clamps finish the weld. Works great when you need that third hand.
P.S. Make sure the slots are big enough so the clamp does not get tacked
to the tube.

[fun4now]

clamps

like the hose clamp ideal i coud have used that tip 3 weeks ago
i too just but the pipe then mig it up with my mm135 just watch the heat if repairing old stuf i use flux i know but it sticks nice and you can do it in the yard

[tackit]

I don't know what your particular job situation is, but when I have an exhaust repair I first go to napa and see if I can buy one of their many sizes and types of pipe adapters and clamps, I might be wrong here, but I feel the repair job will last much longer.

[Sberry]

I do use a few adapters but try to avoid that stuff, even mufflers, weld on. I have my own little system, sawzall the old off and weld a new one in. I live on backroads and welded exhaust lasts so much longer, doesnt come loose and is actually easier to repair. You arent always trying to get a slip fit joint apart. Just saw off. Lately I have been moving the muffler ahead about a foot and coming out ahead of the rear wheel on pickup trucks. It avoids the tailpipe over the axel. I stock some 90 degree 2" EMT sweeps. They outlast couple of mufflers and slide right in the end, re-use them. I weld a 2 1/4 extension on to come out from under the box side and they slip fit into a 2 1/4 muffler end.

[sparky123]

thanks guys. i will be doing this project on saturday. i will let you know how it goes. i like the hose clamp idea, im going to try it.

[Steved]

Here is a question regarding exhaust pipes.

I know that they are welded all of the time but I also know that welding in the possible presence of gasoline fumes is hazardous to your health.

Is there a safe(r) practice to adhere to when welding on exhausts?

Sort of on the same topic: one of the big benifits of a OA is to free seized bolts by heating them, the problem is that I am no nervous about the KABOOM that I rarely do that. Maybe I am ultra conservative as all of my frozen nuts are located on my diesel truck.

Does someone have any advice with respect to safety practices when welding on exhaust and/or heating seized bolts?

[fun4now]

safe

if you smell gas fumes fix the gas leak first, then fix the exhaust

[Sberry]

Yup, I will second that,, good solid advice. Dont blow fire on gas tanks and watch for vapor and fuel lines. To complicate matters now many of these lines are plastic. If I have to I make a heat shield. Clamp a piece of plate or sheet up in the work area.

[Sberry]

With guys like yourself, obviously careful, fires dont happen often,, where they do though is muffler shops where they are in a big careless hurry, mostly semi skilled labor and learn as you go approach.

[sparky123]

the exhaust is done. as far as welding around gas lines and tanks, i did all my welding on a bench then slid it all under in two peices and clamped it in the center so it only has one clamped joint. as far as using an OA torch under the hood i have a scrap of 3/16 plate i used for a heat sheild. something else that helps is a peice of spark arrester cloth you can get at your local welding supply or plumbing supply. the hardest thing i found was not burning though the thin pipe. after some experimenting i discovered you can only mig weld about 1 inch at a time before letting it cool for a moment. maybe this is because i am new and there is some secert i haven't learned yet.
thanks
NICK

[dyn88]

the secret is less heat or smaller wire for thin wall material i always use .023 and sometimes even.013 for the 24 and smaller gauge.

[sparky123]

when i was doing my exhaust i was working out side. the only wire i had was.030 flux core. it was sunday so i coundn't get any more gas or wire. and working outside i was worried about my sheilding gas blowing away. i don't know if this fear is founded or not because i am new to welding and only hadflux core anyway.

[cleaver]

after some experimenting i discovered you can only mig weld about 1 inch at a time before letting it cool for a moment. maybe this is because i am new and there is some secert i haven't learned yet. thanks
NICK

got any pics nick? One thing that might be a factor is the electrical oulet. Since your MM135 draws 20amp current, you will need a 20amp outlet. But if your outlet is the normal household 15amp oulet, you might be experiencing with duty cycle hitting the threshold of the machine. Basically, if your plugged into the normal outlet the breaker from the service pannel will trip sooner because the it only uses a 15amp breaker.

hope this helps...and sorry if I have confused you a bit..