Lotus Elan and Lotus Elan Plus 2 Forums

Not sure where to post this - but.....

Has anyone used this aluminium welding system on their cracked differential casing or timing chain cover?

The videos make it look easy.

http://durafix.co.uk/pages.php?&pID=10

I tried something similar when I broke a lug off the front cover a couple of years ago but I couldn't make it work and in the end I farmed it out to a local engineering company. The problem really was lack of experience - starting from zero trying to fix the lug was too much of a jump and I soon realised the potential to make things worse rather than better. I've still got all the rods etc and it's in my to do list to practice on bits of scrap and try and get a feel for it but the lug was better done professionally.

It's one thing to weld nice clean aluminum. It's totally different to try and weld an aluminum casting that has been soaking up oil for 40 plus years. Near impossible to get the correct fluids, trichlorethylene, to make a vapor degreaser in today's world. Repeated cleaning/soaking with the strongest available solvents is mandatory. Try heating the metal prior to attempting the weld to see if you can coax any oil out of the casting and up to the surface. If you can, then it's back to cleaning before attempting the weld.

Rob Walker
26-4889

I posted this in the thread on repairing a weber cover in the fuel and carb section...

"I've found that "aluminum solders" such as Alumaloy (durafix, and the like would be the same) seem to work on well cleaned sheet, extruded shapes, and sand cast parts, whether old or new. My experience has been that they aren't as good for making sound repairs to investment type cast parts due to the release agents that are added to the alloy. The joint may look good at first but most of mine failed eventually".

The real problem is that these low temperature products don't actually produce a "weld" or blend of the old and new materials. The materials are not heated to the point that the parent metal melts. They are soldering alloys. The joint produced is similar to the one produced when soldering copper pipe, or even making an electrical connection on a circuit board with lead alloy solder.

That's not saying they don't work in the right application. I used aluminum soldering to join aluminum tubing and sheet for a car top kayak rack that has lasted many years with no sign of fatigue or failure. You really don't need an "as seen on TV" product either. Most welding supply houses, in the US at least, carry generic brands for less money that work just as well.

You just have to pick your application well. If you wouldn't "solder" the parts together take it to a competent welder for repair. Oh, and do it before you try using the solder because it will contaminate the true weld.

That's been my experience...

So the consensus is - steer clear.

If needed I have a friend in Birmingham able to weld aluminium and even titanium....