I want to rivet the forward fuselage cheeks and forward outer floor to the firewall but...I can't do that until I install the rudder pedals and brakes but...
I can't do that until I install the forward inside floor but...
I can't do that until I install the forward outer floor but...
I can't do that until I have painted the underside of the fuselage so...
Today I set to to do that. I brief trial proved that painting the underside with the EkoFill primer/UV blocker was not going to be possible lying on the floor. However, without the tail feathers the airframe is currently pretty much neutrally balanced when in flying attitude and the centre of balance moves forward as the tail lifts. So the wheels were chocked and a cable attached to the horizontal stabiliser carry through and very carefully the aircraft was allowed to tip forward until the engine rested on some foam padding. This allowed enough access to the underside to work and get access with the spray gun.
The process is first to clean the fabric with some special cleaner that Stewart supply and then to wash off the detergent leaving the fabric damp. Then the first coat of EkoFill is brushed on with a foam brush. Once this is dry a second coat was brushed on using the brush at right angles to the first coat. Painting the tail while standing on a step ladder was slightly bizarre and the passing local traffic seemed distracted! While this coat was drying I decided to make a first attempt at using the Stewart EkoPoly top coat. I had previously prepared the spinner so this was an ideal test subject. The paint was mixed with the catalyst and then thinned with distilled water and then 4 coats were sprayed on alternating in direction about 10 minutes apart. The first coat came
out as tiny globules of paint rather than a mist. This was diagnosed as having 
too little gas pressure so once this was corrected the painting was much more even. There is a little bit of an orange peel effect but this should polish out and was probably caused by the first coat. After 3 hours the fuselage seemed dry and some 320 grade open coat sandpaper was used dry to remove any blemishes. Then the paint gun was prepared for 4 coats of the primer (2 coats in each direction). These were applied as per instructions about 10 minutes apart and resulted in an even light-proof covering of the fabric. This is critical as the fabric is degraded by ultra-violet light and left outside unprotected will loose 85% of its strength in a year. The fuselage was then gently returned to a more normal attitude and returned to the workshop where the paint can harden overnight.
