Why does Araldite epoxy take so long to dry?
Posted: Mon Sep 01, 2008 6:12 am
This is a question that I asked jackssmirkingrevenge not too long ago. With his permission, I'm putting it up so that anyone with the same problem can search and not have to ask the experts again.
Everything here is summarised:
My Araldite epoxy takes me a few days or even a week to dry for a PVC to tyre rubber (i.e. schrader) bond, even though I live in a tropical climate. For a soda bottle to tyre rubber bond, it takes even longer. Is it the norm or is there something screwed about it?
This is JSR's answer:
Araldite tends to have different properties from the marine epoxy I use for casting. For example, I find it tends to soften when heated much more than the other stuff. I'm not far from the equator myself, once in summer I had left a wooden frame glued with araldite and filled with marine epoxy in the sun to set quicker. When I came back, the Araldite had literally given way with the heat and I was left with a collection of wooden bits in a puddle of hard epoxy. In this case with temperature you can have too much of a good thing. In any case, Araldite never seems to achieve that glass-like finish that marine epoxy does. For starters, getting the exact right proportions when mixing requires some measure of practice, and thorough mixing before applying is always necessary.
Rubber is a hard material to glue, I usually incorporate a physical fastening such as a bolt and washer to make sure it stays in place - what exactly is the sort of join you're trying to achieve?
to the strength of epoxy joints, I normally use Araldite to hold moulds together, with the real strength coming from marine epoxy casting. That said, as long as the surfaces are correctly prepared and there isn't too much of a glue gap between them, it should be at least as strong as normal solvent welding.
I get my schraders from bike tyres too, please look up http://www.spudfiles.com/forums/how-do- ... e-to-a-pla stic-bottle-t7456.html
For the mods, I hope reposting PM convos up is ok here. No intentions of being a post whore or attention seeker, just hoping to try to help out.
Thanks
Everything here is summarised:
My Araldite epoxy takes me a few days or even a week to dry for a PVC to tyre rubber (i.e. schrader) bond, even though I live in a tropical climate. For a soda bottle to tyre rubber bond, it takes even longer. Is it the norm or is there something screwed about it?
This is JSR's answer:
Araldite tends to have different properties from the marine epoxy I use for casting. For example, I find it tends to soften when heated much more than the other stuff. I'm not far from the equator myself, once in summer I had left a wooden frame glued with araldite and filled with marine epoxy in the sun to set quicker. When I came back, the Araldite had literally given way with the heat and I was left with a collection of wooden bits in a puddle of hard epoxy. In this case with temperature you can have too much of a good thing. In any case, Araldite never seems to achieve that glass-like finish that marine epoxy does. For starters, getting the exact right proportions when mixing requires some measure of practice, and thorough mixing before applying is always necessary.
Rubber is a hard material to glue, I usually incorporate a physical fastening such as a bolt and washer to make sure it stays in place - what exactly is the sort of join you're trying to achieve?
to the strength of epoxy joints, I normally use Araldite to hold moulds together, with the real strength coming from marine epoxy casting. That said, as long as the surfaces are correctly prepared and there isn't too much of a glue gap between them, it should be at least as strong as normal solvent welding.
I get my schraders from bike tyres too, please look up http://www.spudfiles.com/forums/how-do- ... e-to-a-pla stic-bottle-t7456.html
For the mods, I hope reposting PM convos up is ok here. No intentions of being a post whore or attention seeker, just hoping to try to help out.
Thanks