"Silver soldering" aluminium

[newshound]

Anyone used these?

I tried something similar a few years ago and didn't find it easy to get a good result (and I am pretty experienced with silver soldering on steel, copper, and copper alloys). That was with thinner rods though. These are quite substantial (50 cm long, 1 cm dia).

[The Natural Philosopher]

I've soldered aluminium usimng carrs flux. Dont breathe it! Works well

Did a bit of oxy welding on it as a prentice. Hard work

[stephenten]

There is a company called superior flux that sell aluminium flux cored solder wire that is based on either 99C or 96S solder which is 99% tin with 1% copper and 96% Tin with 4% silver respectively.

I have personally used these products to solder aluminium but you do need to also buy their aluminium cleaner and you need to solder at 300 degrees centigrade.

The fluxes are very corrosive so you will need to wear PPE and use the aluminium cleaner afterwards to clean off the corrosive flux residues.

Good luck and Ben Baskin at the website is very helpful.

Be aware that some aluminium grades will not solder at all.

The other alternative is to use zinc-tin solders but the solder is very prone to corrosion.

[Marland]

Carrs supply more than one type using a simple system of using a colour reference and matching label according to the intended use. For Aluminium a purchaser should get their grey label.

GH

[The Natural Philosopher]

I assumed UK.D-i-y readers would be intelligent enough to spot that.

My bad.

[Marland]

You have to consider those who may eventually read it on Homeowners Hub or DIY Banter.

GH

[Richard]

I have had success with 'Lumiweld'. No flux. Just scratch about in the solder pool with a stainless steel point to dislodge the oxide layer on the aluminiun