36" all sheet balsa, finishing before paint?

[martin collins 1]

Finishing up a couple of projects, one is an all balsa sheeted 36" model, i don`t want to cover it in film, i was thinking of using Polyspan then a couple of coats of thinned dope before air brushing the matt paint on but the designer Chris Golds used 5 coats of dope/thinners 50/50 straight on to the wood sanded in between as a base for the paint. Anyone on here finish their model like that, if so did it make a nice smooth base for the paint?

[Glenn Philbrick]

I have used poly c in the past. Several coats rubbed down inbetween. The last couple of coats I mixed lightweight filler to make like a cream consistency. This covering gave slight ding proof and took the paint well. Other similar varnishes are available. It does not add much weight and has some fuel proofing as well.

[Martin_K]

I use non shrinking clear dope 50:50 with thinners straight onto the wood. I apply / rub down between coats until the wood grain is no longer 'raised' after a coat. I think ~3 coats covered this model. Maybe I brush it on rather liberally.

 

 

The two black bands at the wing centre are a couple of strips of covering film I put on to hide a 'ding' on the leading edge. The other black areas are paint. I have only ever painted orientation / identification marks, not large areas of colour. The finish has proved durable and the dope repels the amount of water on damp grass. Having only used gloss paint I can't say how matt looks on top of dope.