gas weld aluminum?

[Soundguy]

ok.. just got me a decent set of torches.. am playing around with new capability of using the gas axe to cut and weld with.. previous torch was only good for brazing and soldering..

question.. can yo do aluminum with it.. if so.. any special tips or tricks?

use aluminum stick rods as filler?

soundguy

 

[Baby Grand]

About 30 years ago, in a trade school welding class, I remember the instructor saying that it was possible to weld aluminum with an oxy-ac torch. He said the mixture had to be just right and the flame had to keep covering the puddle so you didn't get excess oxygen into the weld. If memory serves there was also mention of flux. This made a huge impression on me at the time as I couldn't even get the hang of puddle welding steel with the torch without winding up with the filler rod frozen to the work. Never tried it on aluminum, but I suspect somebody here has.
-Jim

 

[BillBeyer]

I bought some aluminum rods at a trade show a few years ago, but they were actually aluminum rods to solder with. Have used them to repair holes in a boat, and sort of used them in brazing rod type of repair on aluminum. Held up so far but would not trust this on heavy usage. Have used aluminum rods with a stick welder with fair success but it takes some practice and move fast. If you try it you will see whaat I mean.
Bill

 

[jbarker855]

I think it would be possible to weld aluminum with oxyacetylene, but difficult to avoid burning through. With regards to gas welding aluminum, hydrogen is the preferred fuel gas, as the temp is about 2300 degrees cooler than acetylene, closer to the melting temp of aluminum. So if you were to go this route, you would need a hydrogen cylinder and a regulator for it. You need to use the right flux and filler rod. I could look up more details on the flux and filler rod in reference book if you were interested.
-Jay

 

[BXpanded]

ok.. just got me a decent set of torches.. am playing around with new capability of using the gas axe to cut and weld with.. previous torch was only good for brazing and soldering..

question.. can yo do aluminum with it.. if so.. any special tips or tricks?

use aluminum stick rods as filler?

soundguy

Yep, works fine. Get the rods from your LWS. They absorb moisture and the flux falls off so make sure you seal them up and keep them dry.
The biggest learning problem is that unlike steel turning red, yellow, white, as it heats, the Al stays silver. It's really easy to melt huge holes in the work. Al conducts heat much better than does steel so a bigger, hotter flame is required.

 

[Mark @ Everlast]

If you don't aggressively clean the metal with a stainless brush, there will be too much oxidation to weld. The metal oxide " skin" melts at 2 x's the melting point of the aluminum itself. The metal underneath will melt but the oxide skin will not change at all and pretty soon you have a big glob of molten aluminum on your feet, or lap. Clean, super clean metal ( not just "shiny") is key.

 

[rhett]

... if so.. any special tips or tricks?

soundguy

The best tip or trick would be to use the proper protective eye wear. The aluminum flux produces sodium flare which the average lens will not filter making it very hard to see your work. The lens are kinda pricey, around $100 +. Here are 2 links:
Phillips Safety Products
https://www.tinmantech.com/html/tm2000.php

and video links:
YouTube - tinmantech's Channel
YouTube - TM 2000 Welding Lens

:drool:

 

[danktx]

You might also want to look at a DHC or HENROB 2000 torch. Same torch different name. Their web site is DHC 2000 Welding and Cutting Torch $369 shipped 803.429.2545.

 

[Soundguy]

interesting info.. thanks guys.

makes me think stick welding aluminum may be more feasable..

that or those alloy rods you use a propane torch with..

soundguy

 

[yomax4]

There are many Aluminum Solder / Braze options out there. For Joining Thin Aluminum check out JW Harris product called ALCOR. Melts at 860 degrees and is very strong. For Filling Holes, JW Harris #52. This is the miracle rod you see at shows only 1/3 the price. There is a flux for it as well. Also CORAL is a nasty liquid flux cored rod but it works. If you use a temp stick to keep your heat under control you can use an Aluminum Stick rod mentioned above. It works well for thicker material. Clean Aluminum with a Stainless steel brush or wire wheel. (Stailness Only ) Set your torch to a Carborizing Flame to keep from over oxidizing the weld. Weld her up...

 

[orezok]

Here's a good video for aluminum brazing. Might not be exactly what you need, but similar.

YouTube - Brazing Aluminum

 

[Soundguy]

thanks for all the replies.

soundguy

 

[BXpanded]

If you don't aggressively clean the metal with a stainless brush, there will be too much oxidation to weld. The metal oxide " skin" melts at 2 x's the melting point of the aluminum itself. The metal underneath will melt but the oxide skin will not change at all and pretty soon you have a big glob of molten aluminum on your feet, or lap. Clean, super clean metal ( not just "shiny") is key.

Another tip: Use a Stainless brush that has NEVER been used on steel. A brush previously used on steel will have picked up a bit of iron and will smear it right into the surface of the aluminum. It can drive you crazy trying to figure out what you are doing wrong.

 

[Soundguy]

sounds like aluminum is very picky about contaminates.

soundguy

 

[Mark @ Everlast]

Picky...very picky.

Any problem associated with welding aluminum, usually goes back to a contamination issue in my experience. Well, that, and it doesn't give a "warning" color when its ready to melt...it just gets a shiny (if properly cleaned) look to the area and then falls through.

 

[sandman2234]

I bought a Miller 330 that the U of Fla traded in for a newer model. Best way to learn to weld aluminum!`tig? David from jax

 

[Arc Angel]

When I went to welding school they required you to weld AL with oxy/ace before you could pass. Was a challenge to say the least. Tig is a mimllion times easier. One instuctor liked to show off using a cutting torch, he could weld very well but boy did he move along the seam.