Chapter 18 - Section 14

Removable Fuselage Top


I wasn't too sure about the plan's mounting method for the removable fuselage top. It does not appear to provide an air tight seal. We placed so much attention on sealing the nose and canard etc., etc... so far, how's the hinge going to keep the cold air / rain out? I searched through the archives and came out with nothing substantial. I also posted the question to the Cozy forum for better mounting methods - with only one response from Marc Zeitlen for recommended improvements. I decided to move forward per plan...under protest!


Carving The Doublers

I decided to make my doubler with a single wood strip instead of two separate pieces. That way, I should definitely get a straight hinge line for the removable fuselage top. To accomplish this, however, I have notched about .5" of the instrument panel next to the longerons. I plan to glass it back in place after the hinges are mounted in place.


I glassed the doublers in place with 2 layers of BID and peel-plied both inside and outside.


I did not install the cover hinges right away per plan. Instead, I jumped forward to mount the canopy onto the side hinges first before coming back to this section... I think I will have a much better idea how the cover will sit once the canopy is mounted. To be continued...


After I mounted the canopy to its hinges and cut out the forward deck in Section 15, I returned to complete the following section...


Installing the Hinges

My side hinges are 17" long and I have to notch a small slot at the sides of the instrument panel to accommodate them. I pre-drilled all the 9 holes on the lower hinge before floxing them in place. I also installed a couple of clecos to keep it in place during cure.


I clamped down 2 straight edges to make sure the hinges were flush to the top of the longerons.



After the flox cured, I used the pre-drilled holes (on the hinges) as a guide to deepen the holes into the doublers. I also counter-sunk the holes on the hinge surface (just a tiny bit with a center drill) to accommodate the heads of the rivets. They turned out reasonably nice. This was the first time I tried these pop rivets...


Here's a picture of the completed hinge. If you look closely, you can see a small slot at the top hinge. The slot is to accommodate the instrument panel.


The hinge rods slide in and out smoothly.