The time had come to make a decision on hinges. Since the hinge pockets required to make the hinge pins removable had still not arrived, and since I had a nice bag of Dubro nylon hinges "suitable for 1/4 scale" (printed on the bag), I decided the Dubro hinges were in. Obviously this would require slotting the parts to accept the hinges, and building some type of reinforcement to insure the hinges had a secure mounting. The first problem was easily solved by using a motorized hinge slot cutting machine - aka the "Slot Machine" by Great Planes. If you don't have one of these, get one. It could be the best $20 tool purchase you will make. BTW - if you go this route, you will also need the optional thicker cutting blades for nylon hinges (another $3.50).
I added small pieces of balsa behind S1 and E1, essentially making them "thicker" to accept the hinges. The same concept was applied to the vertical tail. Here is the horizontal tail after hinging:
Plenty of elevator travel!
With both tail surfaces hinged, the only task that remained was sheeting. First step was to make sure all trailing edges were sanded to a fine edge (includes rudder), leading edges were rounded, and there were no bumps, dips, or irregularities with the ribs. I wanted to make sure the sheeting material was going to make solid contact with the structure at all points. So.....out came the sanding block again, along with a straight edge, and all surfaces were closely inspected. Once complete, it was time to sheet!
There are numerous ways to apply sheeting - but here is one of my favorites. After cutting the sheeting material to size, apply wood glue to both surfaces with a brush and allow to partially dry. Typically 30 min works well, but actual time may vary due to temperature and humidity. You simply want the glue to be reasonably dry to the touch. If there are still a few wet areas, that is OK. Now lay the sheeting in place and use your covering iron (set at about 125 deg C) to press the sheeting down on the structure. The heat will activate the glue and bond the sheeting in place. You may have to hold the sheeting down for a min while the glue cools before it holds, but usually the bond is near instant. This saves the trouble of trying to insure the sheeting is in firm contact with all the structure while the glue is drying.
Here is the stabilizer with the first piece of sheeting ready to go:
And here is the current state of affairs. Notice the blue tape on the tips of the horizontal stab. Initially there wasn't enough glue to close the sheeting at the tips, so I added more glue and taped the sheets together until dry. The elevator is done, as is the rudder. Still need to sand the horizontal, and need some more ply for the vertical. But at last - this "tail" is nearly complete. Only a fuse and two wings to go!
-Mark
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