[Wind Junkie]

I'd go with Bondo and or evercoat filler. Bondo if you need strength.

Both sand great.

Then prime and finally spot putty, sand more prime more.

If the bondo layer will be too thick will add too much weight (ie more than 1/4") then I'd consider removing material, build up balsa from inside with CA/glass and then go with evercoat to get the nice contour you're looking for. Then finish like above (auto body stuff).

 

[Wind Junkie]

I think I'd just go for the Evercoat Glaze now:

http://www.evercoat.com/productDetail.aspx?pID=184

It will save a LOT of primer. This stuff spreads like runny cake frosting and sands much better than bondo, but it's not quite as strong. I use it for easy 1 finger fillets on PSS slope models. It feathers great.

 

[Wind Junkie]

That's the thing.... My dad just ad this silver can of clear liquid he poured into the bondo to thin it a little.... Don't remember what it was or where he got it...

I wonder if it was "styrene monomer?" That's what Fiber Glast recommends for thinning polyester resins.

Evercoat is tits. If it didn't have a shelf life, everyone should have a bottle in their shop. As it is, I buy a new one every year it seems and the old one is only half empty when it gets too hard to squirt.

 

[Wind Junkie]

Even if you goof up, it shouldn't take that long to cure and then you can sand it pretty easily.

A soft rubber or plastic scraper is what I use for big areas like wing bottoms. I just use my finger for small areas.

The feather coat layer shouldn't be that thick right? Even if you need to sand off most of it, you should probably only need 1 more application to get any spots you missed.