Fitting the cowl

Here is a little “How I did it”. With the cowl of this airplane being pretty much flat on the sides and more or less matching the fuselage sides I was able to mark everything pretty well just using tape and a scale.

1) I have the cowl located. Be sure and have your spinner back plate in place and the prop as tight as you will ever get it especially if you are using the stock spinner. I have placed two pieces of tape on each side to use for marking as you will see.
2) Similar to what we did when helping Rich with his cowl I have added 1/16 X 3/16 strips of balsa to help evenly space the gap the cowl has. In the picture it is hard to tell but these are only about 1½” long. (Obviously if you are cutting off the back of the cowl, as some do, this would not apply).
3) The top pencil lines are hard to see and the scale slid over the bottom lines. But here I have marked lines that line up with the top and the bottom of the “mounting flange”. I also measured the distance from the back of the back tape to the center of the mounting flange on both sides.
4) I placed an old glow plug clip on and marked lines on my tape that will line me up with the center of the clip and took a measurement from the back piece of tape to the center of the clip.
5) I did the same for the needle valve as I did for the glow clip.
6) After all measurements were made I replaced the cowl, spinner back plate and prop (just to make sure everything was still in the right place). Moving down 3/8” from the top line and up 3/8” from the bottom line I marked were I wanted the mounting screws. I then drilled holes through the cowl and the wood mounting blocks using my pine vise and a 1/16” drill bit. Both sides.
7) After removing the cowl I pre-fit the screws and soaked the holes with CA after removing the screws. At this time I also enlarged the holes in the cowl to 1/8”.
8) While drilling I noticed the cowl was not naturally laying flat of the flanges. So, I added small 1/16” plywood plates were the holes are and drilled them with the 1/8” bit after the glue dried. This creates a nice fit were the cowl does not squeeze when the screws are tightened.
9) I then remounted the cowl and held it in place with the screws also using small washers cut from fuel tubing. Then I marked were the glow plug hole and needle valve holes should go.
10) Using the pin vise I started with a 1/16” bit and stepped up the drill size a little at a time. Notice I am trying to maintain the correct angle as I drill. I also followed the same process for the needle valve.
11) I used a piece of 1/8” brass tubing (from a fuel tank) at this point placed over the center pin of the glow plug to confirm I was properly centered with the hole.
12) Here is the final fit of the clip.

I also need to mention that I kept my needle valve opening covered during this to prevent getting any chips or dust in it while drilling holes.

Now it is time to mask and paint to match my scheme as well as pull the engine and get some fuel run through it on the stand.