RE: ARF BUILDING
I tried to post this, but it would not take...trying again. I usually reinforce the engine firewall with triangle stock wherever necessary. Add reinforcement to landing gear mounting area. Add a Sullivan tail wheel when th stock one puts stress on the rudder. Also reinforce the bulkhead where the wing mounts by doubling it and change out soft wood mounting dowels with oak ones.
And on large planes I swap out CA hinges for dubro pinned ones.