[TheForge] OT - vinegar vs. epoxy

[Bruce Freeman]

Way OT.

The following quotation is from an article on using seat belt
strapping as the hinge for a small boat rudder.

The interesting part is on the chemistry of epoxy -- i.e., that you
can prevent epoxy from setting using vinegar.  I haven't tried this
myself and am not sure where it would prove useful.  I suspect any
acid would work here, since acids protonate amines and change their
chemistry, but I'm not sure that that's the chemistry involved.


"...you must not allow the epoxy to harden on the strap where it has
to flex. But the ends of the strap have to be well saturated to hold
the slide and the rudderstock halves together. The most successful way
I've used to avoid glue where I don't want it is to get the parts all
glued up and assembled with clamps, keeping the glue off the flex line
as much as possible. Then use a syringe or squirt bottle to saturate
the flex line with vinegar, working it through the fibers, before the
glue starts to set. The acetic acid neutralizes the amines in the
epoxy hardener, so it won't polymerize. The clamped parts won't allow
the vinegar to reach the glue on the strapping between them, so it
goes off where you want it to." "

-- 
Bruce
NJ