Building U Can Do SF whats the easiest way to measure and fit the cowl for os 55 > please help Im almost done but I need help here . Thank you Ken

Andrew,

First install the engine on the motor mount in the plane. Then, take a piece of craft paper, index card or other heavy paper and tape it to the fuselage on the side where the engine will be to make a template. Make sure you tape the paper behind where the cowl will mount. Carefully cut the paper around the engine and everything else that will stick out beyond the side of the fuse. When you are satisfied with what you've done, then simply lift the paper and fold it back. Then install the cowl, lay the paper template over the cowl and mark it. Finally remove the cowl and cut the hole for the engine.

David

Hi David I have a question when you make the template and tape it I understand that but how do you place the cowl on plane to get proper spot to match spinner and allow for small gap behind spinner and cowl ? Thanks Ken

I make a ring of wood that matches the opening on the cowl when bolted on like the propeller. Place your cowl over that and it will dictate where the cowl needs to be mounted. Leave about an 1/8" for the thrust washer to protrude in front of the cowl. This way you get the cowl centered over the prop shaft. Once you get the cowl mounted you can go back and make any holes you need like for the muffler. As suggested above.

Hi!
Like this! Cut and try metode!