This week I had to build up the edge of cowling a bit in three places where I trimmed it too much. I'm using West Systems epoxy fibreglas - I mixed some West Systems 403 Microfibers in with resin to make a very thick slurry. I roughed up the edge of the cowling, and clecoed a strip of aluminum covered with tin foil to the outside of the cowling to be sure I got a smooth transition between the surface of the cowling and the added material. I wasn't sure how good a bond I would get to that thin edge of the cowling, but it seems be a very strong bond. I also had to build up the flat area behind the spinner to get an even gap. I've still got lots more filling and sanding to go yet to get a nice match between the two halves of the cowling at the front.

I tried something a bit different when I fitted the two pieces of hinge at the back of the top cowl half. These pieces of hinge make a continuous curve, due to the fact that the top of the fuselage is rounded. The hinge is designed to take a 1/8 inch diameter aluminum hinge pin, but the plans say to use a 3/32 diameter stainless steel hinge pin instead, as you must be able to pull and replace these pins to allow the cowl to be removed, and it would be impossible to push a 1/8 inch pin around the tight curve at the outboard edges of the top cowling. Even so, many builders report that it is difficult to insert the hinge pins. The instructions have you use the smaller 3/32 hinge pins when you are drilling the cowling to the hinges. But, this means that there is some slop between the two halves of the hinge, and thus the eyes won't be perfectly lined up, which might explain why the hinge pins would be difficult to insert. I decided to leave the 1/8 inch aluminum hinge pins in place when I drilled the hinges to the cowling, to ensure the hinge halves were perfectly aligned right from the start. Today I cut the 3/32 hinge pins, and tried them out, inserting the two halves of the hinge pin by reaching in through the oil filler door - they slipped right into place without any difficulty. Mind you, the hinges were only clecoed in place, I hope everything is still nicely line up after I rivet them.