Chapter 18 - Section 13

Canopy Hardware Reinforcements


I worked on this section ahead of Section 12 (Shaping the Inside Canopy Foam) because I did not want to risk dinging up the nicely shaped foam surfaces. I will wait (shaping the foam) until right before I glass the bottom side of the canopy. 


Aluminum Inserts

I cut up a couple of aluminum strips 1.6"x18"x.16" per plan. I dug out a slight depression on each side of the canopy foam with my short aluminum ruler. Then I spread 5-minute epoxy on the underside of the aluminum strip and weighed them down onto the depression. Though I cut the strip (18") to plan, I think the strip is a bit long. I will find out soon enough.


Notice the 2 small dug-outs I added for the handle? I hope they are in the right place.












Filling in the Hard Points

By now, you should know when the plan says this will take 3-4 hours, it means 6-8 hours or more. It took me two 95o hot summer days. The flox cured fast and it got harder to spread as time flew by. Evidently, my layers of flox were thinner than plan because I ended up using more than 15 BID layers most of the time. Just for the record, the number of BID layers I used were as follows:


  BID Layers   BID Layers   BID Layers
Port rear 23 Port forward 22    
Starboard fore 1 17 Starboard fore 2 18 Starboard fore 3 15
Starboard rear 1 17 Starboard rear 2 10 Starboard rear 3 15
Handle fore 17 Handle rear 21    


I ended up with less BID on the last 2 fillings because the TB flange took up quite a bit of room inside the hole, resulting in less layers of BID.


Here's a picture showing the filled in hard points (canopy handles) being weighed down to cure. Right behind it - is one of the larger cured hard points. 









Now it's time to go back to Section 12 - Shaping the Foam.


Preparing for Inside Lay-up

For me, there was quite a bit of preparation before glassing the inside canopy. I made sure all the foam surfaces were leveled and smooth, the inner edge of the canopy was rounded off, the canopy edge surface roughed up, etc. Since the inside lay-up is similar to the canopy deck, I decided to make a set of paper templates as a guide for cutting the BID and UNI respectively. Then I dug out the small trench along the edge of the canopy frame for flox corners. I also cut two wood strips that have the same foot print size as the hinges (10"x1.1") to hold down the glass at each hinge location for cure.







With everything ready, I applied micro all over the foam surfaces. Next, I mixed some thick micro and patched all the cracks and holes. Then I applied dry flox along the flox corner trenches. Lastly, I applied semi-wet flox along the canopy edge of the foam (the thin light blue strip picture left). Note the duct tape line, the roughed up canopy surface, and the flox line - providing a smooth transition support for the BID and UNI to lay over the inner lip of the canopy onto the foam.


[Hindsight] I had no problem with that transition throughout the canopy edge. I felt good about that preparation. 






Inside Lay-ups (Forward)

The inside lay-ups took me about 8 hours because I decided to wet out the glass first (like a BID tape) before laying them onto the foam. The plastic backing helped to hold the BID/UNI in shape for placement and smoothing out.


Susann caught me wearing only two pairs of gloves (the liner & nitril) without my third outermost vinyl gloves...







Inside Lay-up (Aft)

I did the inside lay-up in two (2) separate steps - the area in front of the head rest bulkhead and the aft ends. The foam at the aft end (pilot side) got beat up pretty good when I was trial fitting the canopy onto the fuselage, many, many times - some repair was in order. First, I removed all the foam around the hard point,









then I fit a new piece of foam around the hard point,











and sanded it flush with the hard point.











Since there are 4 layers of glass (2 BID and 2 UNI), I needed to step it down when joining the glass from front to back, otherwise, I will end up with a bump. My sanding schedule was about 1" step per layer.