Originally Posted by awmeade
The glassfibre over veneer method is quite popular, but trying to answer your questions made me think why! I guess once the foam core is cut, its very easy to veneer the foam by using the female blanks to form a press and hold the veneer on. This of course gives you great rigidity in the skin of the wing where it matters, and also protects the airfoil shape.
Glassing over this is just to create an even stronger finish that resists dings well, and can be finished nicely with sprays etc. If the builder had access to vacuum bagging, I expect that the veneer would be mostly be dropped.
Have you still got the full depth spar I saw in the early pictures? That will make this wing very strong, but it will still have a tendency to twist, which a strong skin will stop.
A ha, cheers for the information, I was under the wrongful impression that foam and a fibreglass skin was enough to strengthen a wing. The wing does still have a full depth spruce spa through the thickest section of the wing. As I think these wings are heavy enough, I have gone with the Water based Polyurethane varnish and brown paper method (even though the paper is white!).
I will be cutting the Polystyrene foam cores tomorrow, and i was going to simply fibreglass over the foam to form the Cathedral tail. Do you think that the tail sections will need extra reinforcement?
Is 175gm fibreglass skin going to add considerable strength do you think?