That was hard, no wounder it costs so much to cover an aircraft. Learned lots, and could look lots better, will see how bad it looks after I paint it. Looks like I still will have to make some test frames, as there is no way to know if light will not pass through the fabric with this seat back.
There is good news and bad news. The Bad news: I Built a test frame, and tried to finish a sample by brushing to see how bad it would look. The goal is to have enough paint/silver mix Trainer Blue Poly Tone so that light will not shine through. Obviously I was not successful. I then removed it with MEK and started over. The re-do did not work to the manual .....more on that later.
The Good news: I found someone at the airport who is there every day, that has done it before several times. We talked about it and I will be showing him my work. The preliminary conclusion is that I did not mix the Poly Tone well and did not keep mixing it before I brushed it on.
Shown below the "cleaned" sample, and about 2 heavy brush coats of Poly Brush and 6 or 7 heavy brush coats of Poly Tone. I think the spot that would not fill in was contaminated by a bad rag when cleaning with the MEK.
Learning lots will try a brand new piece tomorrow and be lots more careful. The manual says 3 coats of special Poly Tone with silver will do the job ......so maybe when I do everything right that will be correct.
Interesting aside, when I called them again today they said they figure a 50% over lap when spay coating.... does that mean 3 spray coats is really 4 1/2 coats or perhaps 6 coats?
Used a really great brush and it does not look so bad. About 4-5 coats but I found out the courser (heavier) fabric is harder to properly coat. I will weigh it to see how much the finishing chemicals weigh. I have the weight before I did anything.
Well the finished weight which includes Epoxy primer, Poly Brush and Poly Tone turned out to be 8.8 oz/yard. I am sorry I did not weight it after the epoxy prime. This is the 2.7 oz fabric, and tapes and lots of Poly Brush and lots of Poly Tone. I will not prime the aluminum and I will be using 1.7 oz fabric.
I got a yard of 1.9 oz non-certified Dacron in. It is much finer weave and should work better with the Poly Fiber appendix A ultra-lite process. At some point I will make another test sample with it.
I have decided to fully detail design the wing in order to know the exact weight and CG before I cut in the stick location. I can move the seat without much grief but the stick requires a large hole in the forward tube and I would like to have it in the right location. Build pictures may be awhile because the wing with spoilers and interface with my original design structure takes time.
Design is moving along nicely. Spoiler assembly, and Rib #1 and horn for the flaperon. Checked weights today, 1/2 wing spar aprox. 14 lb (design finished). one wing Flaperon aprox 7 lb. Original for 1/2 wing was 35 lb, so I do not think I will be far off.
Decided I was sitting at the computer too much, so even though the design of the wing is not finished I started the fabrication of the details of the "Full Span Aileron" This is the plot of the tip. About 1/3 these parts have been made using this plot typically as shown in the log previously. That is a 24 x 36 size paper.
As I post I see what I forgot to do, 60% done of the drawing above, cut bent drilled. Couple more pieces to cut and bend, 4 more holes to drill, remove paper, clean the rubber cement off, glass bead, make fixture, assemble and rivet.
Aileron rib 12 LH RH done less rivets,.... only 22 more to do for the aileron. The drywall screws work ok, faster to set up. Not any more accurate, I am probably within .02 which is close enough for a fabric covered aircraft.
Pouring aileron balance weights. The wood mold works well with a little clay in the corners, back out the drywall screws to take apart the mold and remove the weight, then trim. Wash your hands after handling the lead.