14 replies to this topic

[Benito_S6]

Hi,

I have an old britax sunroof frame, I’m pretty sure it’s cast aluminium. A lot of the bolts were seized so I’ve ended up cutting out. Unfortunately it’s not possible to buy the frame anymore so looking at repairing. I’m looking at building up with weld, shaping, drilling and retapping. Like in this video below.



I’ve put a photo to show the state of what I’ve ground to, and what it should be like. I’m using a sealey super mig and have just bought some aluminium wire. Just wondering if anyone has any advice as how to get best results in regards to the method I’m going to attempt. Thanks

Attached Files

•  IMG_8056.jpeg   35.4K   2 downloads
•  IMG_8046.jpeg   34.31K   2 downloads

Edited by Benito_S6, 15 May 2025 - 09:08 PM.

[DeadSquare]

To get the best results, you need 10 years experience.

 

Aluminium is used in the food industry.  The nearest you'll get to Aluminium welding is Stainless steel, so look through a directory for a Stainless stockist and ask them who buys and fabricates a lot of catering / food equipment, and ask them for advice.

 

30 years ago, I used to be able to weld it with gas.  Don't be afraid to get it too hot but have a thin enough filler, aka rod, to quickly melt and absorb the heat, otherwise it doesn't meld together, just perches on the surface like bird-crap

[sonscar]

In the UK there is a product called Lumiweld which is a sort of aluminium brazing and can be done with a blowtorch.I have had success using it to repair castings.I have uses mig on aluminium and it is best used for truck body building.Tig would be the better option.Steve..

[Benito_S6]

In the UK there is a product called Lumiweld which is a sort of aluminium brazing and can be done with a blowtorch.I have had success using it to repair castings.I have uses mig on aluminium and it is best used for truck body building.Tig would be the better option.Steve..

Nice one thanks for this as I hadn’t heard of lumiweld. Just looked into it and I might end up using this. Whatever route I go down I’ll update. Cheers

[Benito_S6]

To get the best results, you need 10 years experience.

Aluminium is used in the food industry. The nearest you'll get to Aluminium welding is Stainless steel, so look through a directory for a Stainless stockist and ask them who buys and fabricates a lot of catering / food equipment, and ask them for advice.

30 years ago, I used to be able to weld it with gas. Don't be afraid to get it too hot but have a thin enough filler, aka rod, to quickly melt and absorb the heat, otherwise it doesn't meld together, just perches on the surface like bird-crap

Okay thanks for your advice

[stuart bowes]

As i understand it (correct me if im wrong) for aluminum they use electrode negative, i.e the 'earth' lead is positive and the torch is negative, unlike welding steel

 

I had to google it to be sure I'm not trying to be a smart arse lol I haven't got to that bit on the course yet 

 

basically it should mean the heat is more effectively concentrated into the work piece which you need because aluminum dissipates heat 6 times more effectively than steel (hence makes for good coolers and heat sinks, etc)

 

with TIG you'd use AC configuration instead of DC which is different again (google says "because the alternating current helps to clean the oxide layer that forms on the surface of aluminum")

 

also, don't you need a proper air fed mask for this? I would do some reading on it before you start

Edited by stuart bowes, 16 May 2025 - 09:04 AM.

[Ethel]

I've used the ally brazing stuff. There's an art to it, so find something to practise on if you go that way. What I discovered is it takes lots of heat because you have to get the work hot enough to fuse with the lower melting point rod and aluminium is very good at conducting the heat away. When it does fuse you can easily end up with a molten mess as the melting point drops where it's alloyed.

 

Consider using a hotplate for a controlled way to get the heat without excess temperature & a MAPP torch to push the join that bit higher. Clamp everything solid because it'll be liquid for long enough to fall apart until it cools. The surface tension is crazy & a worthy spectacle in itself!

 

It's also harder & a noticeably different colour when it cools.

 

 

I think Aluminium fabbing is more common than it used to be, I also got a cut 'n shut inlet casting welded up for beer money at a local general fabricators some years ago. Though breweries is a good shout & a surprising number of dairy farmers handle a mean tig welder!

[sonikk4]

Although i cannot comment on whats the best process to use i recently watched a very good Youtube channel (Steve Morris) you although is a capable welder with a TIG (he builds very high end Drag and drive Engine in the States)  he visited a one man band Welder who's skill with a TIG was off the scale. He opened up Steves eyes with a technique for welding Aluminium heads and blocks (repairing etc) which probably goes against the norm.

 

You could physically hear the difference in the welding noise and the quality of the welds was impressive plus no pre heating. If i can find it i will add the link to this thread.

 

And although not relevant to this topic this chap also TIG welds Copper. I really didnt know that was a thing.

[sonikk4]

Although i cannot comment on whats the best process to use i recently watched a very good Youtube channel (Steve Morris) you although is a capable welder with a TIG (he builds very high end Drag and drive Engine in the States)  he visited a one man band Welder who's skill with a TIG was off the scale. He opened up Steves eyes with a technique for welding Aluminium heads and blocks (repairing etc) which probably goes against the norm.

 

You could physically hear the difference in the welding noise and the quality of the welds was impressive plus no pre heating. If i can find it i will add the link to this thread.

 

And although not relevant to this topic this chap also TIG welds Copper. I really didnt know that was a thing.

 

Found it.

[stoneface]

Don’t forget that for welding aluminium you need to use argon gas.

[imack]

I've had some success with the lumiweld type of product. It's not as easy as it looks in the adverts, but with some patience and practice it does work and can produce some decent results.

[Benito_S6]

Just wanted to thank everyone for their input on this topic, I’ve got some repairs to do to my r53 this weekend so I’ll probably be tackling this sunroof project some time within next week. Going to go down the mig welding route first, with argon gas of course as I’ve found this is also needed. Trying to get a result as good as the video I posted in my first post. Failing that I will be trying the lumiweld which I hadn’t heard of so much appreciated. I have also been in touch with a local fabricator who specialises in aluminium welding so if I can’t hopefully he’ll be able to!! Hopefully successful updates to follow

[stoneface]

In case you don’t already know and since a quick skim through the video you posted didn’t mention it. Maybe it did and I missed it.

 

MIG welding Ali is best done with a MIG spool gun but can be done with a standard torch with care.

 

With aluminium being much softer using the long torch can cause the wire to bunch up as it’s pushed through the torch lead.

 

Most cheap migs come with a steel spring type lining that causes too much friction and makes the problem worse. To get round this you can fit a Teflon liner instead of the spring type. 

 

Also keep the touch lead as straight and short as possible. You don’t want a coil or kink in the torch lead. And using a larger nozzle tip can help reduce the friction.

 

And some grades of aluminium wire are softer than others so buying a stiffer type can help. I can’t remember the different grades. Google will help.

 

Don’t let any of this put you off trying as what you want to do is perfectly achievable.

Edited by stoneface, 17 May 2025 - 02:01 PM.

[weef]

If you know of someone local who can weld the frame then I would go directly down that route.

It will be a much simpler task for the fabricator to weld the " virgin" frame rather than having to clean off any failed attempts contaminating the area.

It is not a huge area for the fabricator to build up and the cost will be offset if you don't have to buy the products you will need to tackle this job.

This is only my view, as someone who has had to rectify many failed attempts at welding.

[Benito_S6]

This is my thinking now to be honest. As much as I’d love to do it me sen and be happy with the result. It’s going to be easier and probably turn out better. I’ve been in touch with them and will go from there.