Brief Description: Canopy Bubble Trimming Part 7 - The Big Cut - MEH
Prepped for the "Big Cut" which separates the canopy bubble into two pieces - The forward windscreen portion which will be fixed on the forward fuselage and the aft portion that slides with the canopy frame.
First I took a little more material off of the nose of the canopy bubble by using the blade of a pair of scissors as a scraper and drawing it along the canopy edge. This method is described in the manual and leaves a nice smooth edge.
I draped a couple of drop cloths in the cockpit, taping the edges to the glare shield and the cockpit sides to help cut down on dust accumulation since the separation cut is to be done with the bubble in place on the fuselage.
Placed the bubble on the frame on the fuselage, lined it up and taped it into place so that it wouldn't move during cutting. Used a thick sharpie to draw the cutline on the canopy as indicated by where the cardboard template made contact with it.
Double checked that everything was lined up properly and made the cut using the cut off wheel in the die grinder. This step causes a lot of builders a great deal of anxiety but it was a non-event and took less than five minutes. After the cut was complete I was able to slide the aft section of the canopy back with the canopy frame. This felt like a major milestone.
Cleaned up the cut edge of the windscreen portion with my belt sander first with 80 grit then 120 grit. Used the edge of the scissors to break the edges of the cut edge.
Moved the canopy frame to the canopy stand and positioned the bubble on the frame. Moved the bubble slightly forward on the frame from where it had been to get a better fit and close up the gap between the aft canopy and windscreen that resulted from the kerf of the cutoff wheel.
Used the cut off wheel and dremel sanding drums to make relief cut/notches where the frame was preventing the canopy from being pulled in to contact the frame. Once these notches were cut I worked from the aft end forward pulling the canopy to the frame and clamping it in place.