prg,

Here are a couple of rambling thoughts based on your idea…[sm=50_50.gif].

No doubt 1/16” sheet will stiffen things up a bit. But I have to say, the 1/4” X 1/2” perimeter structure is pretty robust for a plane this size.

To go with sheeting on just the stab like you are thinking, I doubt the weight gain would be much. If building the elevators stock, a switch to 1/8 X ?? sticks would be made in order to match the finish thickness of 1/4”.

If I were to go with sheeting on all of the tail I would switch to 3/16” X 3/8” stock for the perimeter pieces. Maybe even 3/16” X 1/4” (doubled up at hinges only). Needless to say 3/16” X ?? for the internal bracing. This would give 5/16” instead of 1/4” for finished thickness after adding sheet. Could even use the 1/8” X ??, then you would finish out at 1/4” thick.

Another thought for stiffening the tail would be to build a light weight (say 1/32” wire) tail brace set-up???

Not having had one of these before I don’t know how they will balance out. But I would rather move the servos and battery toward the tail before adding weight just to get it to balance. Also I would move the engine as close to the firewall as I could get it. The advertised weight of the ST51 is in line with other 40 and 45’s. So I am hoping to not have a balance problem with mine.