I thought quite a bit about "reinforcement measures"... in the end (so far, anyway), I decided to trust Tom's design. Though incredibly light, the airframe interlocks everywhere. The fuselage is a basic box (i.e., strong) with formers top and bottom to give the shape. I put one small piece of triangle stock at the firewall/fuse top junction (you can see it in the pix) "just because". Also, I put extra 4mm plywood "backers" for the 8-32 engine mount blind nuts (you can see those in the pix too), and glued quarter-inch square spruce backers in place for the cowl mount screws.

Now, if I were putting a small gasoline engine in there, I would definitely beef up the firewall/fuse sides area. But for a glow engine, I think it will be okay as issued. Do hit every wood joint you can reach with medium CA, though. Cheap insurance...

Target weight? As light as possible... I'm HOPING to be closer to nine pounds than ten; this engine flew a nine-pound CG Ultimate with authority. This airplane will have less parasitic drag, and nine pounds would be excellent.

Its real easy to make a porker out of a model if you get carried away with "reinforcing". Of course, the flip-floppers go to the other extreme; no cowl, spinner, or wheel pants, midget battery packs that have to be re-charged before every flight, too-small servos, etc.

I'm somewhere in the middle...

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