aluminized exhaust pipe

[mark4561]

I'm mostly a pipe stick and tig welder thou i'm gonna get a mig welder to weld some exhaust pipe. what wire you use for that and any comment's w/ it as well, thx mjz

[sturugged]

exhaust pipe welding

Hello Mark,
I have done a fair amount of gluing aluminzed pipes together. Many muffler shops often use .035 " fluxcored self-sheilded wires, but you will want to either grind or flapwheel the aluminum coating off a bit where your gonna weld. This will weld the pipe together , but you have to be aware this will also be the failure point for rusting out and internal corrosion. I have used cold galvanizing spray to recoat the exterior of welds, but the interior is often impossible to get at. Depending on exactly how long the pipe or connection is you might be able to get the inside as well. I know that for stainless you could try solar flux as a backing paste to stop sugaring on the backside, I dont know if it would work on aluminized pipe. I would try to use mainly lap joints instead of butt welds.

[myistar]

When I weld aluminized exhaust tubing. I take a 120 grit flap wheel on a 4.5" grinver to clean the coating off where the weld will be.

Usually I am under a car, so I tack weld where it needs to be w/ the Millermatic 211 using 70S-6 wire. .030". Then I take the exhaust off, and finish it out TIG welding it. Sometimes I use 309 Stainless, Sometimes just 70S-6, 1/16" Filler.

But that coating really sucks if you weld over it. That's all the input I have w/ the aluminized tubing.

[Desertrider33]

On galvanized tube I use .035 fluxcore and I don't grind off the galvi before welding. Wear a respirator mask though!