Finishing Kit

Over the last few days, I've begun the final prep work for the canopy and the canopy frame, getting it ready for the Sikaflex application. I've also been planning some strategy for the big day. There aren't any instructions for this, so you spend more time than usual planning your strategy. For example, I needed to figure out a way to get inside under the canopy, in order to pull off the masking tapes right after the Sika is applied, but before it cures. I want to do this while the material is soft so it doesn't pull long strings (like taffy!) and make a mess. Or worse yet, completely cure and make it nearly impossible to remove the masking tapes. I have one good friend that had that happen, and I want to avoid that scenario. So I left one seat in the cabin to sit in while I'm in there, and I actually climbed into the baggage area from over the side, stepping onto some boards I laid on the baggage floor, and I practiced sliding in under the seatback bulkhead bar. I'm 6'1" tall, and It's a tight squeeze, but I found that I could make it!

Next, the objective is to mask off everything on the frame that WON'T get Sika applied to it. So you can see in this first picture, I have covered the glare shield vinyl with protective plastic. The white electrical tape follows the contour of the leading edge of the vinyl. Along the sides I have used black electrical tape to protect those areas where I don't want Sika. This is done on both the inside and outside of the frame, all around. It's quite a job masking this all off.

Here's another shot of the front, showing the white tape on the glare shield, and the black tape on the canopy frame skin. The space between the black and white tape (red arrows) shows where the Sika will go down. This narrow area has been thoroughly scuffed and cleaned, then the tape put down.

Here's the left side. These nifty clamp blocks were made and loaned to me by my good friend Bruce Hill. He lives down in California, and he's building a 9A. He was kind enough to mail these to me. The idea is to be able to clamp the plexi to the frame along the sides. He made these himself, using pieces of rectangular aluminum tubing, with one end cut off, holes drilled and tapped.

And finally, over the canopy frame bow I carefully masked off with black electrical tape the area right up to the curve in the aluminum flange where the Sika filet will end. The bare aluminum over the top of the bow has been scuffed and cleaned, like around the sides and front. After applying the black tape, I added short pieces of adhesive paper masking, following the curve. I wanted this all covered up. I didn't take any closeups of the interior side of the canopy frame, but it's masked off right up to the edge of the side frame.

With the canopy frame carefully clamped in the resting position where it will end up, I measured and cut this board. I clamped this scrap flooring board onto the roll bar brace. It has been precisely cut to the right length to act as a canopy stop. The canopy will bump into it as it's placed on the frame, and be prevented from sliding back too far.

I also marked the board with the centerline that I've used throughout the canopy work. It should be easy to match up the line on the canopy with this line, and know the canopy is in the right position.

And now, with the prep work on the frame finished, it's time to turn to the canopy itself. The same principles apply here. Mask off the plexi exactly where I don't want any Sika. The exposed part is scuffed with scotchbrite, and cleaned up. This picture shows the front edge of the plexi. The forward edge of the black tape marks the boundary where the Sika will go, and the blue tape connects the black tape to the protective plastic on the canopy, and will make sure that the plexi is protected during all this work.

Just as with the canopy frame, the canopy needs this careful masking on both the inside and the outside. Except on the aft curve over the top. Only the inside gets this treatment, because there's no Sika on the outside over the top! Just pay attention and think... before you scuff up the plexi or apply the primer... where does the glue go? I also carefully scuffed up any remaining areas of plexi that weren't scuffed up yet, and cleaned it up.

This is now ready to go! I've spent bits and pieces of time over the last few days doing all this work. Tomorrow is the big day for the SikaFlex!

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