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Old Sep 12, 2012, 09:06 PM
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Thornleigh - 20k N of Sydney,N.S.W.,AUSTRALIA
Joined Aug 2001
833 Posts
Rudder Hinge Mods

Rudder Hinge Mods for my P2K
Photo 1 - 12mm (1/2") slot for rudder post cut in rear of tailplane platform.

Photo 2 - Balsa Hinge Post 2plys of 6mm (1/4") hard balsa glued together (didn't have a scrap piece of 1/2" )

Photo 3 - Hinge post sanded to shape to be a neat push fit right down to the bottom of the fuselage to make contact to both sides and the bottom.
When satisfied with the fit, this is glued in place with Contact Cement, which works very well if not allowed to dry out completely, but left to cure for several hours - I left mine overnight.

It is one, possibly the only, type of glue that does work reasonably well with this plastic fuselage, although I would not use it in a high stress area.

Photo 4 - Shows my original and later corrected ... more on this later ... rudder post in place, with the hole for the pivot hinge - (Great Planes have them, or your LHS may) The original rear cooling hole is shown covered over here, but will need to be drilled out for a cooling air exit.
I made an initial error, by cutting away the rear of the fuselage as well. Cutting away the rear of the fuselage is unnecessary.
My error was corrected by adding a piece of 1.5mm(1/16") ply to the now fitted balsa rudder post bonded in place with Cyano. You can see the glue line around this added piece.

Photo 5 - Shows the type of hinge used, under the modified version already fitted into the rudder.
It shows one shortened arm for insertion in the rudder post, but with the other full length arm already push fitted into the rudder - no predrilling is required to do this in the ultra soft rudder foam material used ... it's no wonder it flexes before a hinge is retro-fitted, the rudder having no structural integrity until well above the tailplane.

Photo 6 - The whole tail assembly fitted, as designed as a unit, with the shortened,stub arm of the pivot hinge inserted in the hole in the rear of the fuselage and into the new rudder post.
The pivot hinge arm that is inserted into the fuselage has to be shortened just to make assembly of the tailplane and fin/rudder possible, because the tailplane's cross fuselage joining rod, makes assembly difficult at the best of times. It may be a good idea to vertically elongate the hole in the rudder post a little to make insertion of the hinge pin a litlle easier.

Have to thank Jeebs77 here, who got my little grey cells working on this mod.
Also to do some changes to the under-wing servo tray too ... keep you posted on that one

Daffy
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