I'm playing around with making my own round inlets for the front of the cowl. Time to fire up my Wife's router for the first time, It was her not so popular Christmas present several years ago.......go ahead and laugh I really should've known better....
I ordered a circle jig and several router bits, the first cut was on the circle jig itself to make room for a 7/8 core box bit.
I also ordered a chunk of HDPE plastic to route shapes into, fairly cheap and nothing is supposed to stick to it. I cut my first groove, Man this thing makes a mess!
I filled the grove with a wet mixture of West Systems and Flox topped with a single ply of 8.9 oz scraps, I set a cheap plastic cutting board on top weighted down to try and flatten things out. It worked pretty well, nice flat surface and just a little bit of prying popped it right out.
My original impression is that the ring is too large for my cowling, 6 inch inner diameter is just shy of 8 inch outer diameter. I want to play with making a smaller radius on the inside of the ring and maybe a 5 1/2 or 5 3/4 diameter opening.