Ed,
I'm not sure what you mean when you say that you were told "it was not wise to mix a resin surfaces with epoxy. They suggest that I use resin to set the strips of glass."
Were you told not to use epoxy resin on a polyester resin hull? I've used West Systems epoxy on a number of polyester resin hulls and my understanding is that they are compatible.
Did you use cloth rather than resin thickened with filler in the joint because you were concerned that filler wouldn't be strong enough?
Does this joint "open up" due to flexing?
Sorry to ask so many questions, but I really would like to do this right.
Thanks to all for your help with this.
--Dave