INSTALLING THE CANOPY PAGE 4
The picture above left shows the bubble cut into a canopy and a windshield. At right is a picture of a nice Oriental gentleman who stopped to talk to me while I was cutting. Turns out he is 74 years old and still has a a full time job. He also rides this bicycle several miles each day. That is all I could understand of him. His English was not too good.
I now cleco'd the canopy to the canopy frame to continue the drilling process. The two photos above show several clamps that I used to hold the canopy while I drilled it along the front. I continued to work from the middle to the outside, The left side was first.
The side of the canopy had yet to be cut. Since the square tubing that forms the outboard bottom of the canopy sticks out from the round fore end aft tubes the thickness of the plexiglass I thought it prudent to trim the excess material from the side before the last three or four holes were drilled on each side. I marked the cut line with green tape as before (above photos).
After I started the cut I put two sections of masking tape across the cut line to help hold the scrap after it was cut completely in two (above left). Again, I don't want the excess to just fall away. The last little cut could pop the piece off before the cut is through. If that happens, the canopy could develop a fracture in that area and that would not be good. After the sides were trimmed, I put the canopy on the frame and installed the assembly to check for fit (above right).
Above left is another view of the canopy in place. Above right is the windshield put away for storage for now.
Time to get back to drilling.
Drilling and clecoing, drilling and clecoing. One hole at a time. Center to outboard. Drilling and clecoing.
I didn't trim enough off of the sides The canopy hit the lower frame on each side. I laid out the area to be trimmed with green tape again. If you don't like the idea of separating the canopy from the frame to check something or other several times during this tedious process I don't blame you. This has got to be done sooner or later though and I believe that later has arrived.
I took the two pictures above to show how I clamped the canopy at the bottom while drilling. The canopy had to be allowed to float. The clamps are attached to the frame but not the canopy. They are simply holding the outside edge of the canopy inn alignment with the frame.
The inside canopy skirt, P/N C-759 is attached to the outside of the frame and goes under the canopy to the inside. There needs to be enough clearance between the frame and the canopy to allow this part to be installed. In the photo at left above I am measuring the joggle in the part. It measures .25" (1/4"). With the canopy in place I measured the 1/4' distance from the frame to the plexiglass and marked it with masking tape. I then removed the canopy and put it on the sawhorses for trimming (above right).
Above left is a photo of the excess material being removed from the canopy. After trimming I used fine Scotch-Brite pads in the high speed grinder to remove cutting marks along the edge. At the right above is a picture of excess weld material at the rear of the frame that will not allow the P/N C-759 to lay flat on the frame. I had already started to file it down when I remembered to take a picture.
The two photos above show the welds filed down. The left side was not quite as bad as the right.
Above is a photo of the left inside canopy skirt in place ready to be drilled. At right is a problem that was caused by my earlier decision to keep the P-677 pin mounts square with the canopy track. The top aft edge of each mount is even with the side of the fuselage. I did not take this into account when I decided to mount these parts this way.
The solution turned out to be fairly simple. I simply had to remove the upper aft edge of the mount along the line in the left photo above. At right is photo of the finished product. Later in the canopy fitting process, I rounded the edge of the nylon insert where the arrow is pointing.
The photo above left shows a mistake I made installing the left C-660 canopy skirt. I aligned it with the C-759 inside skirt at the front and rear and marked the front and rear holes for drilling. I then used a rivet fan to install the rest of the holes in the skirt. I put the skirt on the frame and drilled the attach holes to #40. Do you see the gap between the top of the skirt and the tape in the photo above left (arrow)? The tape is aligned with the canopy frame and there is a slight bow. There is almost no edge distance in the plexiglass at this point. What is the solution? I had to make another C-660 skirt. I made one considerably larger than the first one. I drilled the holes from the old one leaving myself more than enough edge distance. See the photo above right.
In the picture above left the "New" C-660 is marked for trimming with masking tape. To mark the upper trim line I placed masking tape on the canopy plexiglass. The bottom edge of the tape corresponded to where I wanted the upper edge of the C-660 to be trimmed. I then put the C-660 in place and marked 1" from the upper edge of the 1" masking tape on to the C-660 in several spots. I put tape on the C-660 so that the upper edge of the tape would be the upper trim line. For the lower edge I put a piece of masking tape on the fuselage and marked it so that the trim line would be even with the forward upper fuselage skin. Again I put the C-660 in place and made several marks the same distance from the lower masking tape. I put tape across these marks to mark the trim line. The photo above right shows the trimmed product. The next page contains a description of the right C-660. There is a simpler way to align the bottom that was not in the plans or on the drawing as far as I could tell.