I have a FTL-45 gas engine on my Patty Extra 300.I used the Dubro heavy duty nylon hinges.
I opened up the slot where the CA hinges go and epoxied these in with 30 minute epoxy.
To keep epoxy off of where the hinge pivots,I melted some vaseline and dipped the hinge pivot
into it with the hinge folded back,then worked the hinge back and forth 3-4 times.Do all hinges like that first for a
control surface,then I installed them on the plane with epoxy and then install the control surface onto the hinges.Set your
hinge line by pushing the control surface on as far as possible,then flex the surface up and down once and let dry.
Never had any come out or loosen.Also you can remove the control surface by removing the cotter pins from the hinges
if you need to.
Here is the hinges I use.
http://www3.towerhobbies.com/cgi-bin...&I=LXD944&P=ML