aluminum welding question

[Soundguy]

Ok, here we go. At work, we use 21 cy aluminum dump trailers to haul dirt, etc. The other day a backhoe operator loading one of our trucks knocked a hole in a non-structural piece of 'decorative' aluminum ribbing on the truck.

The piece from the dealer is way expensive. The local weld shop wants nearly 200$ for the repair.

Our mechanic has experience welding with a wire welder.. and is good at it.. even has some stick experience.. and is good at it.. but he doesn't like it.

We have a wire welder and an old big lincoln stick at work, but I have a small stick welder rig... low is auto up to 40 amps, high is 70 amps... takes the small 1/16 - 5/64 sticks.
I noticed that tractor supply has aluminum welding rods..... in that size..see where I'm going with this. Anyone care to share any hints/tips/advice on stick welding this aluminum? Patch will not be structural, and will be less than 1' x 1'.

thanks

Soundguy

 

[OkeeDon]

My aluminum welding experience is mostly TIG. I haven't tried stick welding aluminum, because my Tig welder is also my stick welder, so what's the point? /forums/images/graemlins/grin.gif My understanding is that it can be done; I've even read somewhere that it's possible to weld aluminum with an oxy/acetylene rig.

But, having said all that, the best thing for your problem may be to use the MIG to weld the aluminum. You'll need a spool of aluminum wire, and switch the gas from mixed to pure argon. And, of course, you have to foolaround with the amperage, speed, etc. Small, homeowner MIGS (like my little 90 amp, 100 buzzbox) have a problem pushing the soft aluminum wire through the torch - it tends to kink and bunch up back at the feedwheel. Larger MIG units should be able to use a stiffer aluminum wire, but the stiff wire requires more amperage than my little unit can provide. If a MIG is going to be used for a lot of aluminum work, it pays to have a torch with the spool mounted on the torch.

A good square wave, AC/DC Tig unit is still best for aluminum (I have a Lincoln Square Wave 175), but when I could get the wire to feed, I successfully stuck some things together with my MIG.

The stick may still be the best solution for you, but that's beyond my knowledge...do a google search for various welding mgrs - Lincoln has some good tech tips on their site - I did a quick search there before posting this to make sure my memory wasn't faulty.

 

[jrlichina]

Check out Alumaloy the stuff works great, you can do it yourself and only costs $45 bucks.

 

[theonlybull]

i've never used stick to weld alum, but i do use mig, and oxy/ace to weld it. even if you have a "biger" mig, it will not push the aluminum wire through the whip. ours has to use an aluminum gun attachment (around $2000 canadian).

everything that i've heard about the aluminum rods, is that they are extremely fickle to weld with. i wish you luck.

 

[n3qik]

I will second the Alumaloy. I have used the stuff before with fair to good results. The key to make it work is a very clean/rought surface. If you do it youself,get some scrap pieces to pracice on first.

 

[Deerlope]

Many years ago when the company I worked for didn't have a TIG or a MIG welder I used stick on Alu. It can be done with good results. If you try it the rods will get red hot real quick, so weld a little then stop. Also when you use half a rod and then start again you may have to take a pair of pliers to break a little flux off the end of the rod 1/8" or so in order to get contact to start again. If the alu has any magnesium in it don't even try to weld it.

 

[johnbilt]

Hi

Sorry - No Stick experience with Aluminum...

I have done a bit of AL welding, but with different MIG machines. I have a Miller 251 with a spool gun, which I purchased to do some boat building.

Aluminum welds different than steel. It melts fast !!, and it is very suscpetible to corrosion or contamination.

If you have the stick welder handy, why not grab some AL rod and give it a try ?? It sounds like you don't have to be overly cosmetic about it for the dump truck. I would keep the stick moving at all times and not dwell in any one spot too long, or poof, holes begin to appear....

Good Luck

John

 

[Hoeman00]

If u have a 10' or less torch on the mig, put a teflon liner in it and run aluminum wire (over 10' u will get bird nesting).
When we refloor semi-dumps we have a Lincoln spool gun ($1100) so we have the reach for the 27' trailers.
Best to get some scrap and go to town practicing.
U will need Argon for the wire.
We have 2 bottles and switch from mix to argon.
Get extra tips because u WILL melt some of them starting out, I know from experience.
Do u haul asphalt in them ?
This will make it tougher to weld and u'll get lots of black from the oils burning.
Use a wire brush on a 9" grinder to remove the oxidation and crap before u weld.
I have to put a floor in a dump truck one of these weekends.

 

[lippy]

something to check out,a welder told me once to only clean the surface to be welded with a s/s wire brush.

let us know how it turns out

larry

 

[Soundguy]

The patch is actually on an outside upper corner area.. so nothing other than dust has ever been on the aluminum.

I'll let you know how it turns out. Patched area will be small.. probably less than 1' x 1'

Soundguy