The Chopper Compendium

I am planning to weld up the intake ports on my 78 Bonneville so I can drill and tap for a TR7 intake and convert to single carb. I know welding cast aluminum is going to suck so I've been practicing on some nice clean sheets. Thing is, I can't seem to get a puddle on the clean stuff. I sanded the oxide layer off, used a new tungsten ground on a new wheel, and a new stainless brush. Just when I think the puddle is forming and attempt to add rod, the arc is too hot and melts the rod about a half inch from the arc.

I'm using a Hobart Tigmate with trimix and have tried two different sized tungstens and 5356 and 4043 rod. WTF!

I'm good with steel but aluminum is kicking my arse!

Any welders have any pointers?

Ken

There could be something technically wrong like the distace of the electrode to the work or the angle of the electrode. One thing for sure is that aluminum likes to be pre-heated.

I pre-heated with my small propane torch but it has been mentioned that it may not be enough. Someone also told me to use 100% Argon. I have an extra tank I can exchange for 100% but I thought trimix was hotter. What do you use?

Ken

Take this with a grain of salt, cause Im no Picaso when it comes to Aluminum.I crank the amps way up & hit it hard till the puddle forms, then I adjust amps with the peddle.Seems the quicker I get a puddle the cleaner it is.Try pulling the torch back just a little as you put the rod in the puddle.

I've used 100% argon from the start. I switched to CO2 mix to see if it would work. I switched back very quickly.

I 2nd what Jeff says.

Got the 100% argon and 100% tungsten (I was trying to use 2% thoriated) today and holy shit! it was like a different machine. i still suck at tiging aluminum so that didn't change but at least I can start practicing now. Thanks guys

Ken

Welding 6061 automotive driveshaft assemblies is tough with 100 argon and pure tungsten. I switched to helium / argon mixed. It was like adding a supercharger to the machine. When the amps get high enough to do 0.120" wall tubing, the damn 50 amp breaker kept tripping. The Helium / argon mix , 2% Thor and our Square wave Lincoln 275 works great.

A good old gray beard I was introduced too, used to build pontoon boats, his advise when struggling w/ aluminum, MORE heat, get in and get out fast. If it takes more than 2 seconds to puddle, you need more heat and faster. It seems to work, so I am a believer.

Good luck

i like this post i cant weld aluminum for shit i have the pure argon and tungston but seems as soon as i get a puddle going poof i got a big ass hole im thinkin im just too slow im used to doing a ton of stainless i been thinkin bout takeing a night class there is noone arround here i kno that does aluminum that i can watch and learn from

Maybe you're startin out with to material thats to thin.Get a piece of 1/4"& just run some beads on that.Youll get a feel of how the Aluminum takes the heat.Then move down to thinner stuff.I want to try the pulse setup on mine, but have never picked up a finger switch for my torch.I've always used pure Argon & 2% thoriated.What really gets me about the Argon is they hit me with a " hazardous material" charge when I get a bottle.

It will take awhile, but this web site has some killer info:

http://www.weldingtipsandtricks.com/

Well I couldn't get my torch in the intake ports so I had to farm that out but I was able to fix a broken fin while I have the head off
Before

After

A little more filing and a shot with the sand blaster and it should look stock

nice work

Yeah, what he said.

Thanks guys. I have a lot more work to do but garage time is slim with a 4 year old consuming most of my time.

Ken

Nice job on the fin repair.I have to do the same with one of my rocker boxes