Hey Lawrence: I have successfully sprayed latex but thinned it with Windshield Washer Fluid instead of water, thinning it till it would spray without running or globbing - trial and error. It did take several coats and I let it dry to touch before adding another coat, then let it dry several days - I think the test is to pinch it and see if you leave a finger print. If so, let it dry more (the finger print also disappears). Most important, if this is a nitro fueled plane it MUST be sealed - I used Poly Urethane. Latex exposed to nitro fuel turns into a gummy mess.
I have been flying the Pink Floater for about a year, repaired and patched touching up with latex, sealing with Poly Urethane and have had no problems.

Mell