On Sun, 24 Aug 2008 09:28:06 -0700, Brad wrote:

When we made my fuselage, it was winter and we were heating the shop
with a propane heater. Propane releases moisture during combustion.

Yes, quite a lot of moisture. A back of the envelope calculation says
that every pound of propane burnt produces just over 1.6 pounds of water,
so you get an imperial gallon of water from 6 1/4 pounds of propane.

Have you any idea how much propane you might have burnt that night?

I'd put money on the water being the problem. IME the worst low
temperature can do to good, well mixed epoxy is to lengthen the curing
time. We used to say that Araldite glue must be cured a bit above the
maximum temperature the item will be used at or it would soften in use,
but I don't know if that's a general rule or specific to that formulation.

Bad luck though. I can't think of many more irritating ways to find out
about the bonding problem.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |