Fastback 57

So today was a bit of a mess. Things didn’t go as smoothly as I would like. My goal for the day was to bond the canopy to the skirt. However, I had a few remaining tasks. First, I needed to prepare the skirt – sand and clean the mating surfaces. Second, I needed to prime and paint the glare shield. The glare shield is the primary area where things went a bit off.

Additionally, my buddy Mike brought his welder and generator to the airport so that the taxi plate could be welded to the roll bar base. I will have it properly welded in the future, but there is no good way to clamp this in place for transport. In order to get it perfectly lined up, you’d need to create a jig, or you can do as we did – position it, delicately clamp it, and tack weld it for transport. I’m not messing with the roll bar – I’m going to let someone else do all the welding and prep work. I’m not well set up for that kind of work currently, so I’m going to let someone more experienced and better postured do the work.


First we clamped the plate in place and then raised and lowered the canopy. This took several iterations. Only the very edge of the plate is on the roll bar, and its difficult to get a good clamp where it stays in position. Finally, after a bit of trial and error we got it precariously clamped long enough for Mike to put three tack welds on.


Here is the result. Now, I will need to tack weld the nut on for the pneumatic arm, and the roll bar assembly – rather someone else will need to do that!


Then I needed to paint the glareshield. I did this now so that I could get a relatively even application without the canopy in place. Where I screwed up was during priming. Impatience got the best of me, and I sanded a bit too early. The resulting mess meant I needed to sand more down, wait and reapply the primer.  My second SNAFU was not having any flat black paint. I have semi-gloss, and gloss. I could have sworn I had all three – but alas, I didn’t. So I had to do a Lowe’s run.



Then it was canopy bonding time. Here is the Hysol 9430 that is recommended by Showplanes. The 9430 is an excellent adhesive for dissimilar materials and a better match for this application than flox or epoxy due to the thermal expansion characteristics. I did a test run last night, and while the stuff is pretty thick to begin with, it gets rather runny after you mix the hardener. To mix, I used a digital scale for a 100:23 ratio. I used popsicle sticks for the main adhesive, and a syringe for the hardener.


I used a one inch cheap paint brush to apply the adhesive. I applied a thick layer to both the inside of the canopy and the skirt before mating the too. Mike helped me here, and a second set of hands is highly advised.


When placing the canopy initially, it was evident that there were several areas of air pockets and insufficient adhesive. We solved this with a syringe and application in a couple areas. First, we applied adhesive in the seam from the inside of the cockpit. Second, we applied adhesive forcefully through the “flox rivets”, and finally we also applied adhesive through the cleco holes. For the clecos Mike pulled the clecos out and injected the adhesive while I was on the inside blocking the hole with my finger. This worked very well. In the end there were only a few minor areas where there were air pockets in the adhesive and they were very small.


We were also able to get most of the “flox rivets” or better called “adhesive rivets” filled as well.


Big chore done! We’ll see how it looks tomorrow.

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