best metal to metal glue

[Wideboy]

what do you use?

tried a few 12hr epoxys in the past but they always eventually let go. Thinking of trying gorilla glue?

[tigersaw]

I keep hearing about JB weld but I've never seen any

You can get it on ebay or amazon it seems

[Wideboy]

cheers, just purchased some so shall give that a whirl

[DJ123]

What metals are you trying to glue together?

[embee]

Surface preparation is critical. What metals, what environment, what sort of loads etc? Basically, what is it you want to do?

Glues tend not to be good in "peel" situations, and not so good in straight tension. Work best in shear.

[Wideboy]

glueing RE magnets to brake discs so its going to be under some force. The last resin i used (can't remember the name, it was industrial grade) lasted a long time but it still stayed elasticy/rubbery (if that makes sense) so it was inevitably going to let go.

just for reference i can't screw in the magnets like they're suppose to be as they're not OEM disc's, the spacings would be wrong.

Stick or mig weld?

[embee]

JB Weld is basically just an epoxy filled with aluminium powder, good stuff but in principle no better than a straight epoxy. Slow setting ones generally end up stronger.

If it doesn't set hard there's something not right, wrong mix, not enough or too much hardener etc.

Surface prep is the critical thing. I'd use brand new fairly coarse abrasive paper immediately before applying the glue to ensure completely clean scratches for the glue to key onto. I'd lightly clamp them together, but not so that all the glue is squeezed out. Keep it warm but not hot to cure.

Is there no way you can drill the disc and fit round magnets in with a high grade Loctite, a retainer or bearing fit grade like 638 or similar? A much more secure arrangement.

[Pete7]

Don't forget epoxy resins are softened by heat and break down in sunshine but if your last attempt was soft then as Embee says there was something wrong. Araldite is used to repair Army helicopers, but the packet goes in the disposal locker straight afterwards so an old opened packet isn't used ever again on flying machines. Okay on landrovers though.

Pete

[Wideboy]

its wasn't completely rubbery, it was a new packet and mixed properly but it must of broken down, off the top of my head it had been on there for 2 year, it also set a pale dark green in colour. All the others are still on so it must of been a bad surface under it.

i'll give it another go in the week and make sure its clean and keyed up