Q. I have some epoxy glue joints that are not very strong. I know the surfaces are not too smooth, and that is why I am using epoxy. I have increased the pressure but with no luck. What next?

A. Epoxy, although expensive, should give you an extremely high strength joint, filling in gaps from uneven surfaces. Hint: Use UV-stabilized epoxy formulations for exterior exposures.

Here is your problem: You have probably noticed that epoxy generates heat as it cures. However, in a very thin glue joint (possible from high pressure or from a low spread rate), there will often not be enough glue to generate enough heat to cure the epoxy. The end result is low strength.

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