Mig welding Alloy piping Help Plz

[danny_lad]

Hey people..

Im looking for some advice my friend has a Mig Welder (Gas) and im wondering could we use this to weld Alloy?

this is what im trying to weld..

I have tryed the Brazing Method and it isnt working for me As the alloy Is becoming Brittle and falling away Even though i got it to the correct temp...

I also have a large spool of Alloy Mig 5356 wire will this be any good todo the pipe..

 

[shenion]

I'd braze it. There is more than just getting up to temp. Once the brazing flows over the weld, you need to stir up the oxide that has formed. Usually easiest to "tin" it and while hot, brush with a SS brush. Then add a filler coat. I use and old 1.6mm steel welding rod to again stir the pool and break up the newly formed oxide.

I have Alumaweld brazing rods. Came with a video. I assumed it was the same hyped up commercial. It showed the fixes repeatedly failing and how to avoid the problems.

5356 wire tends to crack when cooled on many alloys.

 

[pedrobedro]

Is the piece you are welding in aluminium as well as the tube? It looks like it needs cleaning up a lot before anything will stick to it. You need pure Argon to mig aluminium, it may be easier to find someone with a tig welder and give them a tenner to do it on a quiet day.

 

[danny_lad]

Thanks Guys..

Could i Use the 5356 wire to weld both pipes up with a mig gas welder spool?

 

[hotrodder]

Is the piece you are welding in aluminium as well as the tube? It looks like it needs cleaning up a lot before anything will stick to it. You need pure Argon to mig aluminium, it may be easier to find someone with a tig welder and give them a tenner to do it on a quiet day.

^ This, especially the bit in bold as the nipple looks like it's a different material or at least coated/filthy

It'd be cheaper to pay someone than buying the correct gas and liner. Obviously once the kit is payed for it can be used for other things but thin ally and MIG ain't easy or fun, especially with smaller DIY type kit which often ain't powerful enough to weld thicker ally (where MIG makes more sense). Kit aside that job will be a nightmare with MIG, especially if you want it airtight and/or neat