Below is my post from the other day.  Just wanted
to follow up to the numerous replies -- thanks
all!

I got replies in three groups (1) watch the mixing
ratios (2) watch the temperature (3) you may have
a bad batch.

I had leftover JB in my mixing containers from the
first two applications.  I brought it inside (20C)
and it did harden up more than it had.  Unfortunately
bringing the block inside the house is not an option!

I mixed up another batch, weighing the quantities of
resin and hardener.  Left it inside overnight and it's
much harder than any of the other batches.  So most
likely the batches I was making were too small and I
got the ratios slightly wrong as a result.  A perfect
example of penny wise, pound foolish!

I cleaned the old JB off the block.  Here's what I did
to mix the most current batch:
1) measure out equal amounts by weight using a scale
2) mix for 60 seconds
3) put in microwave for ~10 seconds  (epoxy gets much less viscous)
4) mix for 60 seconds
5) apply
6) waited 6h.  Pointed some lights at the block.  Shrouded the whole
thing with blankets.  (It's ~5C here -- wouldn't have to do this
if it were warmer!)

So -- watch your mixing ratios and temperatures!  If you're
paranoid, mix some up beforehand as a test batch.

--tabe

--- tabe johnson <xtabe@yahoo.com> wrote:
> Gooped up my corroded block yesterday.  Waited 24 hours.  I
> put a light near the JB weld because it's been cool.
>
> The epoxy is still soft.  When I poke it with my dental probe
> it feels like a cavity as opposed to a piece of hard metal.
>
> How long does it take this stuff to dry?  Is the ratio of
> resin to hardner especially finicky? Does it need to be
> mixed for an unusually long time?
>
> tabe johnson/87 westy/vancouver bc

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