Welding Aluminium

[njl]

I have a SIP mig mate welder, which I have used for welding steel, using both gasless wire and normal wire and a CO2 gas bottle. The only difference in set up is the polarity of the gun connections.

I've got a small repair to do on an OS FX46 aero model engine to re-attach the needle valve holder to the backplate, and I happened to be browsing a Machine Mart catalogue when I came across a page in their welding section showing Aluminium wire and Argon gas bottles. Can I just use these items on my mig welder and weld Aluminium with it in a similar way as I would steel? If so what is the correct polarity of the connections, same as for steel and CO2 gas? If it is possible to use the mig welder for Aluminium are there any gotcha's I need to be aware of?

Nick

(Just posted this a while ago and it just dissappeared, so am posting again. If I'm out of line in some way asking this question here and it was removed for a reason please tell me, being new here I'm still feeling my way.)

 

[black85vette]

Just posted this a while ago and it just dissappeared, so am posting again. If I'm out of line in some way asking this question here and it was removed for a reason please tell me, being new here I'm still feeling my way.

Nick, a number of posts went MIA this afternoon. Don't think it had anything to do with your topic.

 

[njl]

Thanks black85vette, not just my post then, that's good to know. Thm:

Nick

 

[John Rudd]

Nick I to have the same setup, a I understand changing the gas/wire is all thats needed..There's no means of changing the polarity either..

 

[njl]

Thanks John that is good news, for some reason I had it in my head that you had to have a TIG welder for Aluminium. Sounds like I should get some Ali wire and a bottle of Argon and have a play. On my set the transformer and gun connections are brought out on screw terminals so you change the polarity. I think all that does is make the spark jump the other way. I'm not sure why doing that is required for the gas/gasless set up but it was in the manual for welding steel.

Nick

 

[John Rudd]

Hmmm interesting...Dont recall reading having the swap awiring about when going from gas to gasless or v-v....Although havent used mine with gasless wire even though its a gassed setup, mine is the Clarke version..

 

[hopeless]

I have a similar welder and use argoshield when welding SS or stell and pure argon for ally. My brother was a boilermaker and when I wanted to weld ally he said to make sure I use a teflon lined hose (forgot the name and he has passed on so can't ask) that the ally wire feeds through as it is prone to sticking.
Works for me

 

[Metal Mickey]

There is another alternative and perhaps less expensive approach, that of Durafix sytem. I wrote up my experiences here http://www.mikes-models.com/allyweld.html

For small jobs I can't speak highly enough of Durafix.

 

[njl]

Thanks for the info chaps, you've given me food for thought.

John as I understand it, not all mig welders have a reversable polarity option so your set may not require it.

Nick

 

[Julian]

Hi,

Rods similar to the ones Metal-Micky mentioned are in B&Q for £3 for a pack of three if you only want to weld small parts.

Regards

Julian

 

[njl]

Cheers Julian,

That does sound like the cheapest option for this repair job.

Nick

 

[Julian]

If you go to B&Q dont bother asking the staff. Go to the tools section where they sell the benzo gas blowlamps and welders. Grey packets hanging up with the braizing rods.

Julian.