Technical Welding cast aluminum intakes- setting up the machine

Straight argon clean clean clean. If it weeps clean again. Mick ordered me a little deal that sharpens the tungsten correct every time. I have actually welded with balled tungsten and with tapered. Each has its place even on aluminum. It’s not supposed to work but it did. I actually am using an air cooled 175 square wave Lincoln. Yep it’s Stone Age but it’s paid for.Use thin goat skin gloves. Also don’t minimize space issues.Practice hand setting and make sure you have complete access/angle clearance for you cup. Learned that the hard way too. Listen to what is being said about mismatch materials. Was welding up radiator bungs. Thick to thin and dissimilar alloys. Probably the hardest thing I’ve ever welded. It holds and still looks better than a bunch of fittings but it is no perfect stack of dimes. Usually a bunch of sbc /etc/abused junk early manifolds around at a swap meet for cheap. Learn on it and sell it once you’ve fixed it. Time is your friend. All the info here is spot on. But nothing replaces seat time. Also make sure your hood gives you good visual. A simple helmet change gave me the biggest improvement I’d had in years. Don’t sweat it. You’re good.

 

There is a local retired industrial welder who repairs outboard props. He builds them up and reshapes them back to original with TIG. People take their aluminum work out to him for repair. He TIG'd my friends boat. It may be less stress & easier if there is anyone in your area that specializes in props or aluminum repairs. If someone who knows what he is doing welds it for a few dollars that may be money well spent vs trying to learn to do it along with the risks. There are lots of alloy grades of aluminum. Determine what grades are most common for cast and if there is a grade of weld rod available that is close.

Oil contamination has been mentioned here and is a problem with cast as it is difficult to get out. I worked in a mill where the welders were allowed to fix reasonable things for fellow employees off the clock. The welders would put parts like a boat motor lower case under a welding blanket and steam it for the better part of a day to reduce the oil contamination.

Would it look ok to drill it through and put a polished SS slotted set screw in that looks like it may have been there for a reason in a previous life?

 

Great thread, lots of good information here for us "hackers", thanks

 

I think what I may try, is opening up the hole until it is round, drive an aluminum dowel in it (interference fit) and back drill the dowel hole using a new intake gasket for a guide. That or forget about the dowels and remove them. This intake weighs 30 lbs less, so dowels may not be needed. Still thinking this through. I really wish I had an ace welder around here to ask or to hire.

What about baking it in the oven to get out any impurities like they do for powder coating?

 

You bring up a good point about impurities as aluminum is very porous. I once had to weld an aluminum oil pan from a '32 Ford. Every time I struck an arc I could see oil bubble to the surface. Even after the owner sent the pan out to a company that did some sort of heated vapor de-greasing it still caused me problems. I don't think that an intake manifold will be as troublesome as an oil pan though. I don't think heating it in an oven will do much.

 

This list may be useful.
Great thread!
https://www.sciencedirect.com/topics/materials-science/cast-aluminum-alloy

 

I do not know much about welding aluminum but from what I found welding older castings is the type of aluminum your dealing with. My old Ford heads were cast with 355 with a heat treating of T-5, which is apparently really tough to weld. The newer stuff is usually cast with 356 with a heat treating of T-6, which is far easier to weld to. You might want to practice on crappy old casting before you try on the real thing.

 

Welding is very easy, did all the time, Argon, Mix'd gas, Oxy, Acet , Tig, Mig etc after a while
you'll be amazed that why did I even ask the question.
Enjoy have fun.
Mike