Tig weld facing on AL manifold

Not a great description of what I want to do but:

I have a new aluminium carburator manifold that I need to build up to a greater thickness on the mounting face, so that I can then face it off to a different mounting angle. I need to add up to 0.25". I was planning to pre-heat, weld on beads succesively, and build up the thickness required. Should I focus on one area at a time to full thickness, go around the flange several times adding a little at a time, what do I need to worry about as far as post heat and cracking?

Machine is a Lincoln SQW 175. 3/32 electrode, lathanated, normal shield, what current should I use? The flange is generally 3/8" thick.

Thanks, Brian

Reply to
Brian
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OK to start you will be pushing your machine hard.

Preheat the manifold in an oven for a few hours at the highest temp it will go, say 450 - 500 degF.

Pull it out with thick gloves and wrap it in a heavy wool or welding blanket.

Keep as much of it wrapped up as possible to keep the heat in while you work.

Rent a bottle of 75% helium / 25% argon. This will boost your heat considerable and that way you won't fry your machine.

1/8" ZIRCONIATED tungsten. Either a #8 gas cup on a standard collet body or a #8 cup on a gas lens collet body.

Wear a heavy glove on your torch hand to protect it from the heat of the aluminum manifold.

Because your machine has a small 125 amp air-cooled torch you will need to cool it down manually, and often. Better would be to invest in a larger 150 - 200 amp #3 series air cooled torch. The larger torch will take the heat better. I recommend a small muffin fan with a cradle in front to rest the torch in while it cools.

For filler rod you will need some 3/32" 4047 rod. Check your local dealers to see if any of them have some. You can also check local welding shops to see if they have any that they will sell in small quantities.

With the piece at heat, how you weld it won't matter that much, just do it as quickly as possible. Once done, throw it back in the oven for an hour. Then turn off the oven and leave it alone, in the oven, overnight.

Reply to
Ernie Leimkuhler

If it were me, I'd just have (or buy) a .25" spacer.....

erie

Brian wrote:

Reply to
erie patsellis

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