12386Views12Replies

Author Options:

Can't epoxy metal, help appreciated. Answered

Picture of

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.

12 Replies

user
steveastroukBest Answer (author)2011-11-19

Try sanding, then degrease carefully with alcohol. 5 minute epoxies do tend to be weaker than longer curing ones.

Steve

Select as Best AnswerUndo Best Answer

user
buffysissy1 (author)steveastrouk2011-11-19

It's sticking to the nut though, just not the other piece

Select as Best AnswerUndo Best Answer

user
buffysissy1 (author)steveastrouk2011-11-19

Tried it, it still snapped off after drying for about 6 hours

Select as Best AnswerUndo Best Answer

user
buffysissy1 (author)steveastrouk2011-11-19

Any brands you might suggest? Thanks.

Select as Best AnswerUndo Best Answer

user
knife141 (author)buffysissy12011-11-19

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.

Select as Best AnswerUndo Best Answer

user
buffysissy1 (author)knife1412011-11-19

Thanks, I'll try it. do you think the slick surface is keeping it from sticking?

Select as Best AnswerUndo Best Answer

user
steveastrouk (author)buffysissy12011-11-19

No, but it needs to be "chemically clean", and sanding and alcohol will get it there.

Steve

Select as Best AnswerUndo Best Answer

user
buffysissy1 (author)2011-11-20

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.

Select as Best AnswerUndo Best Answer

user
steveastrouk (author)2011-11-20

So you're putting a flash foot on what looks like a tripod mount ?

Steve

Select as Best AnswerUndo Best Answer

user
buffysissy1 (author)steveastrouk2011-11-20

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.

Select as Best AnswerUndo Best Answer

user
rickharris (author)2011-11-19

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.

Select as Best AnswerUndo Best Answer