welding cast aluminum

E

emnick

Well-Known Member
Joined
30 Sep 2003
Messages
721
Location
Essex
Visit site
Is it possible to weld cast aluminium. I have a steering quadrant and have found one of the stops broken off. Its a substantial piece of cast at about 8mm not sure how it happened or how long its been broken. I only found it today when routing a cable. Its a whitlock steering system (rod type).

Any recommendations appreciated if it can be repaired.
Thanks
 
Take it to someone who specialises in aluminium welding. (Obviously). I had a cracked lug welded on a gearbox by a friend who is an engineer. It was entirely successful.
if it's possible they will probably heat it first and then weld it. Because of the size of my gearbox and the fact it was still full of the gears, he used his TIG torch to heat the area before applying the rod.

N_Sgearboxmount01.jpg
 
You could also try HTS2000 aluminium brazing rods - it makes a very strong weld with only a propane or MAP gas torch - you can google demos on Youtube. I've heard it shouldn't be immersed in salt water because of it's zinc (?) content, but above water and especially painted, it should be ok.
 
A good professional will be able to perform a great job: "AC TIG" is the only way. Beware of any different way of welding; I once trusted an "old time skilled" welder who used aluminum stick welding on a transmission crankase and it was a total failure.
I am afraid I would not trust aluminum brazing rods as well.

Daniel
 
Welding alloy is difficult because it absorbs so much heat, so as a previous poster says, it needs to be heated up first. It's also porous and soaks up oil, which then oozes out and messes up the weld. Taking the part to a specialist is the best option. Welding it yourself in situ is the worst option, unless you have a lot of experience at welding alloy.
 
I have used a system called Lumiweld. You clean the parts with a stainless steel wire brush then heat the part with a propane torch and apply the welding rod, which melts, and scratch through the pool of molten rod with a stainless scratch rod. The scratching breaks up the surface oxide layer on the aluminium and the melted welding rod forms an alloy with the parent metal. I have repaired broken components with it, but is does need practice and some skill as it is very easy to melt the original component, because the alloying temperature is only just below the melting point of the parent metal. Although I could make the repair that way, I would still rather take it to a specialist welder.
 
danielefua said:
A good professional will be able to perform a great job: "AC TIG" is the only way. Beware of any different way of welding; I once trusted an "old time skilled" welder who used aluminum stick welding on a transmission crankase and it was a total failure.
I am afraid I would not trust aluminum brazing rods as well.

Daniel
Click to expand...

I've successfully used HTS200 rods on above-water parts of a seagull outboard, and if you look through the various videos online, a modicum of skill can perform wonders with them. I imagine an expert aluminium TIG welder might struggle to weld a hole in an aluminium drinks can, for example :) The weld is stronger than aluminium, apparently, and it seems very good at replacing broken off lugs etc from castings, even to casting the threads inside the hole. However, if I'd an Ovni with a hole in the hull, I'd want it properly welded!

Norman_E said:
I have used a system called Lumiweld. You clean the parts with a stainless steel wire brush then heat the part with a propane torch and apply the welding rod, which melts, and scratch through the pool of molten rod with a stainless scratch rod. The scratching breaks up the surface oxide layer on the aluminium and the melted welding rod forms an alloy with the parent metal. I have repaired broken components with it, but is does need practice and some skill as it is very easy to melt the original component, because the alloying temperature is only just below the melting point of the parent metal. Although I could make the repair that way, I would still rather take it to a specialist welder.
Click to expand...

I think the Lumiweld is similar to HTS2000 brazing rods, though the HTS2000 melts well before the aluminium. (having said that, a MAPP gas torch on a Seagulls Villiers carb and it started to melt though it was of 'pot metal' rather than any decent alloy
 
danielefua said:
A good professional will be able to perform a great job: "AC TIG" is the only way. Beware of any different way of welding; I once trusted an "old time skilled" welder who used aluminum stick welding on a transmission crankase and it was a total failure.
I am afraid I would not trust aluminum brazing rods as well.

Daniel
Click to expand...

Check how all the old timers welded up those fighter aircraft during WW2. Now there is real skill.
 
ALUMINUM WELDING AND FABUCATION NICK WHITLEY 01245 464669 cm33ad

Nick has welded two sets of steering quadrants for members of my club, one was in three pieces! The other had a stop snapped off. The one broken in three cost about £75 I believe. The post code is Borham Essex.
 
You must log in or register to reply here.

Share this page

Top