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I’m building a B, and it looks to me like the canopy, once installed, cannot be easily removed. This hinge is riveted to both the cockpit longeron and the canopy side frame. And the hinge pin is held captive at both ends by the windshield support and turtledeck hoop. Am I missing something?

I noticed that issue on my XENOS. When I built my OneX, I modified the hinge pin. Instead of one I used two. I also removed one lug from the lower hinge pin half (the part that is riveted to the longeron). This way I could insert one pin from the middle forward, and the second from the middle to the back. Easy to remove.

I am not familiar with the B model canopy attachment design but on the older A models it was generally advised to not use rivets to attach the canopy to the frame as the canopy had a high chance of cracking from the force of the rivets. Instead, many builders used machine screws that went through an oversized hole in the canopy and into tapped holes in the frame. This made it so you could adjust how much tension was being put on the canopy once it bottomed out against the frame. You could also sequentially tighten each screw a little at a time to try and spread the tension out. Some builders even went so far as to eliminate holes in the canopy all together and instead bonded the canopy directly to the frame.

Keep in mind that this was on the early A models. Sonex eventually changed the canopy material to a more flexible and pliable material in order to try and solve the cracking problems builders were having. It was so bad at one point that many were buying 2 canopies with their kits in anticipation of having one crack during installation. I am guessing that it may not be an issue on the current B model because I don't see many posts about cracked canopies anymore but if you switch to screws instead of rivets it at least solves the problem of removing the canopy to replace it without having to drill out rivets.

Two hinge pins seems like a great idea. Thanks.