Aluminium Welding

[SpaceCadet]

This was my responce to "Dennis Jewitt's" question on Aluminium - one of the last messages sent to the old list server. I at least would still be interested in any responces.

Original Message follows:

I have a Frost (http://www.frost.co.uk) catalogue here (volumn 26) and they are advertising a product called Lumiweld (http://www.frost.co.uk/item_Detail.asp?productID=8823). They say that it is similar to brazing using only a butane blow lamp as the heat source, and can be used on alomst any grade of alumimium resulting in a joint stronger than the parent metal.

I have never used it, but thought it might be interesting to try. Maybe someone else on the list has tried it ? Maybe a solution for you as well ?

Regards
/Ian

[e-mail]
pws.prserv.net/idm/

[Lee]

I once seen a aluminium boat hull repaired with a similar product this was at a boat show the bloke doing it made it look easy. You can use a bar of soap as a temperature guide you mark around the repair area, when the marks go black that is max temp.

Lee

[Tel]

Yeah, I saw this stuff demonstrated at the Bathurst show some years back & bought a package. Now while the bloke doing the demo made it look easy & could do anything bar solder two tiger snake tails together with it, I have had a singular lack of success.

[Lee]

There is a thread on Home Shop Machinist BBS on stick welding aluminium. Something I hadn't heard of before. There is also a number of threads on "Aluminium Solder" none of them favourable
bbs.homeshopmachinist.net//Forum1/HTML/006981.html

Lee

[meyerga00]

Aluminum can be welded quite well with DC if the polarity is correct such that the oxides are removed from the puddle. This is generally the way the MIG machines are set up. The problem with aluminum feed wire is that if there is too much drag in the cable setup then the soft aluminum wire balls up in the drive wheels greating a real hairball effect. The true commercial MIG machines set up for aluminum use a gun that contains a small roll of filler wire thus eliminating the long push through several feet of teflon tubing and resulting snarls/hairballs of wire. Generally high frequency AC is used with TIG for AL welding as the proper polarity with DC results in a fried electrode in short order.