low temperature ally welding

Hi out there,

anybody used the "Lumiweld" low temp welding for ally kit.....

Fluxed or un-fluxed rods whats best.......I have an oxy/accet plant and quite used to welding - brazing of steels but never ally......

I would normally just get a company to do the job but I don't live in the UK, so I'll have to have a go myself.......

the job is to modify a ally casting ( avery flat timing cover, (1960's NSU) and to extend the timing case for a repositioned timing chain tensioner.....the extension is about the size of a Swan-vesta match box, pre fabricated from 4-6mm ally plate.....

any experiences ?

thanks for any help...Frank in France....

The guys who demonstrate this stuff at the engineering shows make it look good. Others may have been able to use the stuff, but I have never had any success in welding large bits of aluminium alloy with it.

Unless you can afford to risk scrapping your rare 1960's NSU casting, I personally would not risk it. Could you find a way to bolt the modifications to the timing cover with M2 screws?

I would tend to agree with Mike. I have used it, years ago, it works more like soft solder than weld, but the newer stuff is said to be different. I would use a mix of screwing and epoxy.

Frank,

I reported a bit of experimentation I did here which you may find of interest.

HTH

Rod

Hi Frank, I have used this Luminweld and it works but I practised on a scrap piece of ally first ,it does take a bit of getting used to . Many years ago I repaired a hole in my mark v Douglas cylinder head cover , but if it has any strength I do not know.

Best of luck Maurice

It does work and it works well as long as you use it correctly.
The idea is to heat the workpiece to a high enough temperature to melt the rod when placed upon it - just like brazing or soldering. Melting the rod in the flame causes it to sit on top of the joint without flowing into it.

I've had success by doing the above whilst probing through the molten pool with a stainless steel scriber to scratch away the oxide that forms on the aluminium parts. This allows the pool to get under the oxide skin and bond firmly with the parent metal. I believe that once the alloy is in contact with bare metal is reacts in such a way that removes more of the oxide and so increases the bond area.

Of the five or six jobs that I have done this way, none have failed, so I'm quite confident in the product.

Martin.

Frank, the other way is to find someone with a TIG welder set up for aluminium welding, and let him have a go.

Ian S C

Frank,

For more info and guidance on this aluminium joining alloy go to www.cupalloys.co.uk

Select "Other silver solder" and scroll down to find Technoweld

In the description of the product find the link to Youtube.

Copy and paste this link to your browser and see how to use it.

Oxy-acetylene is too fierce. Use propane/air

Experiment first on scrap to get the feel. Strength should not be an issue.

Product is readily available

Keith

Hi Frank

When I served my time some 50 odd years ago we didn't have Migs and Tigs but a welder showed me how to weld Ally, get a candle and light it smoke the Ally where you are welding put your flame on it and when it turns pale grey stick your rod in, have a go on a bit of scrap it works for me.

Good Look

Stan