Instructables

Can't epoxy metal, help appreciated.

I'm trying to epoxy two pieces of metal together, I'm mixing the epoxy the right way but once it hardens the piece breaks off, any suggestions? I'm gluing this flat piece of metal to the nut that's glued on the viewfinder.  The nut stays on the viewfinder with the same epoxy so I'm confused about why the other metals won't adhere, should I sand the pieces first? By the way I photographed the wrong side of the flat piece, the side showing has prongs, the other side is flat, the flat side gets glued to the nut. This is a viewfinder from an old Mamiya press camera, not sure what kind of metal it is.

Picture of Can't epoxy metal, help appreciated.
Devcon-5-Minute-Epoxy.jpg
Try sanding, then degrease carefully with alcohol. 5 minute epoxies do tend to be weaker than longer curing ones.

Steve
buffysissy1 (author)  steveastrouk2 years ago
It's sticking to the nut though, just not the other piece
buffysissy1 (author)  steveastrouk2 years ago
Tried it, it still snapped off after drying for about 6 hours
buffysissy1 (author)  steveastrouk2 years ago
Any brands you might suggest? Thanks.
We use Araldite.
JB Weld works great on metal. Roughen up the surface first and clean with alcohol or acetone. Let it cure for 15 hours before handling.
buffysissy1 (author)  knife1412 years ago
Thanks, I'll try it. do you think the slick surface is keeping it from sticking?
No, but it needs to be "chemically clean", and sanding and alcohol will get it there.

Steve
buffysissy1 (author) 2 years ago
Ok, pulled off the nut that you see epoxied, drilled some extra holes and screwed it on. But hey, at least I know now how to epoxy metal. Thanks everyone for the tips. Happy holidays to all who celebrate.
So you're putting a flash foot on what looks like a tripod mount ?

Steve
buffysissy1 (author)  steveastrouk2 years ago
No, this was the original foot to the viewfinder that you see here, I took it off and cut a notch in it so when I reinserted it into my G11 it wouldn't stop the flash from going off. I lost the screws that hold it on so decided to glue it back but epoxy just doesn't work maybe I'll solder it.
rickharris2 years ago
When you stick things together you are using one of two methods.

Either the glue fills the small spaces at an molecular level and the parts and glue are attracted by the atomic forces.

OR

You use a liquid to fill in minute blemishes on the surface of each part. The liquid glue then solidified (usually dries or polymerizes) and the connection becomes rigid - Epoxy is in the latter category and needs those imperfections to get a grip - So as the advice above. Scratch the surfaces.
Pro

Get More Out of Instructables

Already have an Account?

close

PDF Downloads
As a Pro member, you will gain access to download any Instructable in the PDF format. You also have the ability to customize your PDF download.

Upgrade to Pro today!