acdii,

I would use clear nitrate dope to seal the balsa.

You have to consider that I am a "dope man".

Apply it with a brush. Donot spray it.

I am not really qualified to advise you concerning Monokote on plastic.
If no one shows up on this point of view I would think that a test can be made.
It would depend on the type of glue used by Monokote on their film.
I would use some 180 or 220 grit before application.

Zor
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