windscreen fairing advice

[prkaye]

I'm thinking about how to do my fiberglass windscreen fairing, and two possibilities come to mind.

1) mask the entire area, put mold-release over all of it and lay-up a fairing which I can then pop-off and trim/sand away from the plane. Then when I'm happy with it use West Systems 406 to glue it in place.

2) Do the layup directly onto the windscreen/forward skin, letting it cure right to the parts. This way is non-removeable.

The pros and cons... (1) has many pros: I get more than one shot at it if it doesn't come out well, I can trim and sand it without touching the windscreen, I can do all the pinhole filling with it away from the plane, etc. But (2) seems to be the more common approach, and maybe a lot less work. My big question here is how do you trim/sand teh edge of the fairing where it is attached to the plexi to get a perfectly smooth transition, without damaging the plexi?

Thoughts?

[schristo@mac.com]

I just finished mine last week and the electrical tape worked great to protect the plexiglass during the extensive sanding process. I used two layers of tape that were different colors. Final sanding was with a single layer of tape. I used the thicker 3M tape (88?) rather than the cheap stuff.

[RV8R999]

ingenious use of a standard sanding block! I've bee contemplating this task for a long while. I'm assuming the black tape overlaps the yellow underneath?

What did you do to keep the inside edge (inside the cockpit) transition from the windscreen to the top skin nice and neat? I was thinking of filling the gap with epoxy/micro and using a shaped scraper to form a nice bead along the inside. Then when this sets, lay the glass on the outside over it all. Thoughts?

Assuming also you painted the inside section of top skin under the windscreen first or no?


Ken

[schristo@mac.com]

there is no need to try to fill from the inside, the canopy gets quite a bit of attention in fitting it closely to the skin so it will be pretty close; i used a strap to hold the canopy fixed during the initial fill of a flocked resin. i also used black epoxy dye in my mix incase there was any visible gap and painted several coats of flat black within the boarder of the dash formed by the canopy before attaching it for good.