Another way
I used a Dremel with stone that I ground to the proper countersink. Not that critical with the method I'm going to describe.
1) Get the countersink done so the washer fits flush.
2) Scuff the bottom of the Tinnerman. Scuff the glass
3) Use epoxy/micro/flox to bond the tinnerman to the glass
4) Sand the edges, then fill with edges so the tinnerman is nicely blended to the glass
5) Put a layer of light glass cloth over the filled area. Use Peel Ply over the cloth.
6) Sand after cured. Cut the hole out where the screw goes.
7 Use a high build primer to fill the glass weave. Sand, repeat as needed.
Now you have a nicely fitted Tinnerman that won't cut into the glass. I used this process on my tail fairing on my 7. Only 8 total. You'd never know there is Tinnerman there but yet I have a solid base for the screw.
If you'd like pictures, send me an email to
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