The idea is to slide the carbon paper in between the canopy and the front bow with the carbon side facing down so it touches the blue tape that has been put on the front bow. Then, while applying slight pressure on the canopy to ensure contact with the bow, carefully pull the carbon paper out. This should cause a slight friction between the paper and the bow and therefore leave a visible black mark in the blue tape.
Ready to try! I started on the pilot side as this one was more accessible. While pulling on the paper I made sure that I applied pressure along the canopy where it touches the bow.
This is the mark after the first paper has been pulled out.
As you can see, the carbon paper left a very clear mark. I continued with the rest of the papers, repeating what I had done before.
It left a very legible mark all across the bow. It might not come through in the picture too well without looking at the full size picture but I assure you that I had no trouble seeing the line on the blue tape over the whole length of the bow.
Before marking and pre-drilling the rivet holes into the bow, I wanted to make sure that I had a sufficient fit. I read through three or four blogs and examined the pictures. What I saw indicated that I still needed a little detail work.
It turned out that my fit on the aft bow was not good enough and would have left quite a wide gap between the canopy and the aft window. In order to pull the canopy further aft, I had to slightly trim the hole for the latch handle as it wouldn't allow me sufficient travel otherwise.
This put the canopy aft far enough for a tighter fit with the aft window but it will also require me to trim off quite a bit material on the aft end of canopy to make this happen as some areas are extending too far aft. I will not tackle this problem now other than to ensure that I will have enough material in that area for now.
After this step, the canopy came off and the rivet holes on the front bow where marked in 2" distances across its length.
I also pre-punched the spots where I had to drill as the bow would otherwise easily allow your drill bit to wander off. Then I pre-drilled the spots with a #40 bit,
The canopy came back on, was readjusted and taped down to hold it in place during the delicate first few holes until the clecos would do the job.
And then the drilling started. I deviated from the plans in this step as the Avery toolkit provides for a #27 and a #40 plexiglass bit but not for a #30. I wanted to make sure that these rivets would sit tight enough and therefore I created a lot more work for myself. As you can see in the image, I started pre-drilling the canopy with a #40 plexiglass bit using the hand drill which gives me excellent control. I clecoed as I drilled along.
Then, when all the holes had been drilled in #40, I started from the center again with two drills now. First I widened the hole in the plexiglass with a dull #30 bit (drill with an old bit into concrete or a brick to dull it). This dull bit won't catch on exit and it heats up the plexiglass very well to avoid any chips or cracks.
Then, I used the hand drill again, with a sharp #30 bit that would drill through the aluminum into bow. I tried it with the dull bit once and it wouldn't really do it with the hand drill, so I chose this method instead. A lot of work but I cracked the aft plexiglass window and I certainly don't want to do this on the much more expensive canopy. No chance!
This shows the process at a bit more than half the way. No cracks, no chips, but a lot of time ... Eventually I was done with that and it was on to the aft bow. This had a special surprise for me as it required the holes to be drilled and clecoed ALTERNATINGLY on the left and the right side. As I only have one single ladder that would get me in the right position to drill the upper holes, I had a fun time (NOT) carrying the ladder from one side to the other while making slow progress.
On this task I also deviated (due to a lack of #30 plexiglass bits) by pre-drilling with #40 plexiglass bit, using the hand drill and then opening up the hole with the dull #30 drill bit. Again, no problems, but it required very accurate positioning of the #40 bit to correctly center it on the #30 hole in the aft bow.
Before working on the next step of matching the side skirts and match-drilling them, I decided to take the canopy off as I had not cleaned up the edges from this protective cover yet and I wanted to make sure this couldn't disturb the delicate fit of the skirts. I also used this occasion to deburr the holes drilled in the frame as well as in the canopy - at least on the side that doesn't get countersunk soon.
Once I was done the daylight faded and all I could do at that point was to put the canopy back on the frame and take a couple of finish photos. The skirts will have to wait.
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