Rear End of Rotisserie

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 The forward end of the fuselage was easy to attach to the rotisserie fixture.  Several metal strap clamps were formed over the fuse tubes and simply attached with wood screws to the plywood panel that was used to spin the frame.  The rear end of the fuselage was more problematic.  Several protruding parts such as the rudder stops and hinge bushings were in the way of trying to flush mount the tail end of the fuse to the spinning plywood disk.  I discovered that a drill press vise had a sizable clamping area and was already “V” grooved for tubing.  A good snug turn on the vise handle kept the fuse nicely attached to the rear rotating disk of the rotisserie.

Motorized Rotisserie

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The fuse became noticeably heavier to turn as I continued to attach more parts.  Without redesigning the rig I attached a hoist motor at the base of the rotisserie and strung the winch cable to a pulley at the top of an 8 foot aluminum mast. I then redirected the cable downward and attached it to an “L” channel that spans the rotating plywood panel. This arrangement allowed me to spin the fuselage from zero to ninety plus degrees in one direction.  To spin the other direction all I needed to do was disconnect the cable and reattach it to the other side.  This proved to be very helpful especially when it came to the Poly Fiber Fabric attachhment and painting process.

Later, after the airplane was completed I used the same motorized mast to help raise the tail for tailwheel repairs, weight and balance computations and adjusting wing dihedral angles. In this case, I attached the hook and cable directly to the welded lift handles on the fuselage.

Back to the Belly Panels

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With the fuselage painting completed, it was time to reattach it to the rotisserie and it would stay that way for the next two years.  Over that time I would complete the belly panel installation, floorboard project, interior sheet metal attachment and the complete fabric attachment  and painting process.  

The belly project continued with the trimming and fitting of the fixed and removable belly panels. The fixed sheet metal panels were attached with Avex pop rivets to the “Z” channels. The removeable panels were designed to slip fit into a forward slot created by an overlap of the adjacent fixed sheet metal panel and secured to the sides and rear edge of the openings with #8-32 machine screws that connected to fixed anchor nuts on the “Z” channels.  It was at this time that I made a deliberate decision to standardize on #8-32 machine screws and anchor nuts on all detachable sheet metal skins versus using sheet metal screws.  This would add time to the project since anchor nuts are time consuming to install but for as many times as I had to take these panels on and off it has been well worth the effort.  Sheet metal screw holes would have enlarged and become an unreliable means of connection over time.

The forward belly panel was fabricated with clear Lexan.  I originally tried clear acrylic (Plexiglass) but it turned out to be too brittle.  The Lexan is very tough but is easily scratched and is not as optically clear as the acrylic.  The clear Lexan panel is located just below the control sticks and my thought at the time was to have a glass port in the floorboard that could be used for targeting a belly camera or for general observation of the passing landscape below. During flight testing I quickly discovered the oil from the breather line would cover the Lexan belly panel and make it useless to see through, even with an Air/Oil Separator.  This was more likely to occur when I filled the crankcase with over 6 quarts of oil.  If I maintained a maximum of 6 quarts there was no oil blow back on the belly.

Another very useful purpose for the clear Lexan panel was for preflight inspection of components that would otherwise be unobservableable. I could easily inspect from above and below the torque tube, push-pull tube, aileron pulleys, brake line connections, hydraulic lines, fuel lines and fuel selector valve.

Preparing the Fuse

Fuselage on RotisserieThe newly purchased fuselage was attached to a homemade rotisserie fixture on wheels.  The fixture supported the fuse and allowed it to be turned and held in place for welding parts on, attaching floorboards, installing components, and for fabric covering and painting.

The fuselage stayed on the rotisserie for 4 years until it was removed for sand blasting and painting.  It was then re-attached and the rotisserie was motorized for easier turning. It stayed attached for another two years for fabric covering and painting until it was finally removed and let to stand on its own wheels.