Hi.
Slow Araldit is a good glue for hardwood but basically all epoxys with slower than 1/2h curing time are strong enough for anything we glue.
Once I had access to a machine for pull-testing differend things, so I made lots of shear-strenght tests for differend glue joints.
The main conclusion was that when cured in room temperature, epoxies faster than 30min were allways weaker,
this is due to the fact that the glue starts to harden before it has impregnated the wood deep enough.
In elevated temperatures (60..70C) all joints got a lot stronger and difference betseen slow and fast epoxies were no longer so big.
With slow Araldit the joint strenght doubled when cured in elevated temperature.
It's not only about the impregnation, also the mechanical properties of glue improve in elevated temperature.
So, I recommend to heat the parts allways when it is possible. You can use an oven, hairdryer or a light bulb for heating, for example.
The 24h Araldit cures in about 30 minutes in 70C.
The only problem with Araldit is quite bad temperature resistance, it starts to loose its strenght quite dramatically allready in 60C, so it is out of question in more serious aeromodels. But good for everything in our stunters.
A much better slow epoxy that is easily available at least in Europe, is UHU Endfest 300. It remains strong up to 180C, and you can manipulate the mechanical properties by changing hardener:glue ratio. Less hardener results in a harder glue with best temperature resistance. Put more hardener, and the joint remains more flexible. L