The Jeffco with the slow hardener gives plenty of working time, not as much as Hysol, but enough for 3 people to close my ES fuselage halves in a 60 degree hangar.  It is much less succeptable to exotherm.

Mike,

 

I have heard that too.  Maybe a builder should have both hardners at hand.

 

Low temps and dry air are ideal - a positive for north of the Mason-Dixon line.

 

Hmmmmm, I did have a problem once on a lovely fall morning with the north garage (oops, builder shop) doors open.  A good sized lay-up over nomex pre-preg started to form voids as the sun quickly raised the shop air temperature.  Saf-t-poxy was very slow curing in lower temps and the expanding air coming out of nomex cell pores did the damage (the other side had already been sealed with primer).  Oh well, nothing a little re-do couldn't fix since it was caught before it cured.

 

You had help?  Maybe that's where I went wrong - a grumpy guy alone in the garage, sniffing epoxy and listening to self-help tapes.  It is so hard to psycho-analyze oneself while wearing a dust mask.