Started TIG welding aluminum tonight...

[jsudar]

I decided to play around with the TIG welder tonight. It's a pretty old school Lincoln unit, but the torch is water cooled and we discovered the arc starter still works. It doesn't have an amptrol, but it's still a TIG

I messed around on some steel to get warmed up, but then I decided to try aluminum. AL is weird stuff. It gets all plasticy when its hot. Once I tried to cut a transmission case in half with the Oxy/acetylene torch. Didn't go well.

Anyway, it seems to take a long time to get a puddle started and then when I dip the rod in the arc seems to blow the filler away. I am dragging the puddle with the torch and bringing the filler in from the back. I tried pushing the puddle and bringing the filler rod in front of the torch, but that didn't work so swell. I made a couple decent beads, but I wonder, am I missing something?

Any experienced Tiggers out there that can help a brotha in da hood?

 

[Tacoma]

PM Redd.

 

[ricsrx]

TIG weldin

I have been tig welding for years because i have access on one at work, I liked it so much i even bought one for home. I am a jounyman electition by trade so am not a pro welder, doing aluminum is very tricky, cleanlyness is every thing, if there are any impurities your tost, if you clean your metel with an unclean brush or any thing unclean or contaminated the bead will not start, I made a tank for my quad, turned out ok but i had to get tank sealer to fillin the pin holes. my advise.....practice.. practice... practice...
your desire to do it puts you way ahead of many.

 

[cheepin]

I like to push the puddle with the torch.Works better for me.I have been trying to teach myself for the last year or so.I haven't touched it in a while.

 

[reddman]

Use green tungsten, and don't grind it to a point. Before you start on you aluminum, clean your tungsten, turn you machine to DC+ and ball up the end of your electrode on a piece of steel. Just apply heat til the tip of the tungsten melts into a ball, and let it cool. The balled up end keeps the tungsten from splitting.

Brake clean is your friend, hose it down and wait for it to completely evaporate. Buy a little stainless wire brush and only use it on clean aluminum, never anything else.

It sounds like you are holding the filler too close to the arc. Dab your filler quickly, and pull it back.

If it takes too long at full throttle to get a puddle started, you either need to preheat your part (if it's thick), or turn up your current.

Hope that helps.

 

[bobdog]

Use green tungsten, and don't grind it to a point. Before you start on you aluminum, clean your tungsten, turn you machine to DC+ and ball up the end of your electrode on a piece of steel. Just apply heat til the tip of the tungsten melts into a ball, and let it cool. The balled up end keeps the tungsten from splitting.

Brake clean is your friend, hose it down and wait for it to completely evaporate. Buy a little stainless wire brush and only use it on clean aluminum, never anything else.

It sounds like you are holding the filler too close to the arc. Dab your filler quickly, and pull it back.

If it takes too long at full throttle to get a puddle started, you either need to preheat your part (if it's thick), or turn up your current.

Hope that helps.

You forgot to mention returning the machine to AC to weld right? I have never used the DC positive to prepare the tungten but I will next time.

 

[ricsrx]

Redd, if your still listing, when I did my tank all of my pin holes were where i Had stoped one bead and started another, I tried every thing but the brake clean, how do you prep it, I guess if it was not a tank it would not have mattered.

 

[Bob B]

I agree with redd.. I usually will ball the end like he said, but I use a REAL copper penny to do it. When the arc is applied to the penny it will ball. Like Redd said it sounds like you are trying to dip the rod in the arc, you should be adding the rod to the leading edge of the puddle the pull it back, but try to keep it in close enough to allow the shielding gas to still protect the rod from contaminents, but far enough from the arc so it doesn't melt.


AND practice! Thats a big one. AL is just tricky, so practice and try not to get upset when you blow a hole in it... Eveyone does it.

 

[reddman]

Redd, if your still listing, when I did my tank all of my pin holes were where i Had stoped one bead and started another, I tried every thing but the brake clean, how do you prep it, I guess if it was not a tank it would not have mattered.

How did you cut the panels you were welding together? (I know it sounds unrelated, but it may be relevant) If you plasma cut them, that is likely a big part of the problem. Plasma cut aluminum welds like @$$ unless you grind it clean. Another note, if you are grinding on aluminum that you are planning on welding, use a clean grinding disk that has never ground steel or other metals. Small particles of steel/other contaminants get imbedded into the disk and transfered to the aluminum and contaminate your welds.

The most likely culprit of your leaks, imo, would be overlap or lamination. Basically, instead of having a molten puddle and dipping the filler in it like the process should be, you could have been melting the filler onto the solid surface of the aluminum, which looks like a weld, but doesn't create good fusion. The resulting laminations will leak.

 

[astjp2]

www.tinmantech.com has some great info on welding aluminum...he perferes Oxy/Acty but still good info. Tim