Thread: Build Log Carbon Sally "Thepasty"
View Single Post
Old May 24, 2011, 01:09 PM
DudleyLeRoux is offline
Find More Posts by DudleyLeRoux
scratch build everything
DudleyLeRoux's Avatar
South Africa, KwaZulu-Natal, Botha's Hill
Joined Aug 2009
1,221 Posts
The best solution I have found is to 3M77 some CF or heavier glass onto the leading edge (use a lot of 3M77 or it will come loose when you wet it out). The gluing can be done before the layup onto the mylar starts. As soon as you start laying up the fabric onto the mylar, wet out the leading edge fabric until it is really shiny, don't stress about adding too much epoxy, it'll be fine in the vacuum bag. I do this with a foam roller and really push the LE fabric against the foam. With this done, the mylars need only reach the leading edge fabric to create a good leading edge although I cut my mylars so that the just barely meet at the LE. I have not found it necessary to sand the mylar edges with this wing. Since I've been using this method I have found my leading edges conform perfectly to the foam and produce an airfoil true LE.

I also sand my TE down to a fine point and allow the mylar to overhang by no more than 8mm. This is then trimmed down about 1mm past the foam TE once out of the bag.

It might also be interesting to know that if you are using peel-ply for your hinge, you do not want it to extend past your foam TE as it will leave some unsandable fluff. The only way I have managed to removed this fluff is by burning it off with a match.

When I have to rebuild this wing (it's bound to happen) I will pre-cut my servo wire channel and create a cabosil/epoxy mouting point in the wing before bagging it. I'll also add my aileron reinforcement to help with flexing of the ailerons.
DudleyLeRoux is offline Find More Posts by DudleyLeRoux
Reply With Quote