Fixing an alloy cap to an alloy tank

Bikes coming along with the borrowed engine but need advice on securing the new Monza petrol cap To the alloy tank. The tank has a welded ring to sit the cap on but I have been told that the new Araldite & unleaded no longer work as well as they did.
I have been recommended Devcon metal putty.
Your view please?
Thanks
Chris

alloy cap to alloy tank

Hi Chris, Devcon works well, JB weld is a better choice I think, if you can get it in the UK -- I'm in the US.
Good luck. James.

Thanks

Thanks James


I have heard of JB Weld so will have a search for a supplier in the UK.
Devcon is available at my local car store so I am covered.
Thanks once again for the help

Araldite, DevCon, JB Weld are all two-part epoxy/amine adhesives. If one fails then I expect they all will.

Why not have the cap mig welded (or is it tig for aluminum)?

Or Lumiweld it?

Thanks

Ron
Thanks for that information. I used a metal putty at Cadwell last year & it worked well to stop a not so blind hole leaking on the tridents chaincases.
LAB I have some sticks of lumiweld in the garage & had not thought of using it.
The cap has the threaded neck
But the tank boss does not. The cap sits on the top of the boss with a fibre washer in between. I though a resin / adhesive would work better within the gap to fill the spaces.
Chris