painting

[JC]

Hi all

 

is it possible to paint directly onto balsa and if so how do you prepare the wood to accept the paint. What paint would you need?

 

Jon

[Dusty]

Jon,

 

The answer is NO! The surface needs some kind of a finnish before appling paint directly onto it, foam and depron is similar but dependant onto the finnish you desire?

 

Here some refs:

 

here,

 

here,

 

Depentant on what covering material, paint etc would determaine what underlying coat, glass cloth, varnish, dope surface to paint onto after the wood is "primmed"! What model, what colours how much weight can you play with?

 

P.S I am sure the balsa bashers will be along soon, I am only a "foamy" so balsa is not really my material. But Oracover seems to be the easiest way to cover your model then paint! will always be old school vs new school technequies I guess but will boil down to weight and surface area of wood? "IMO"  

 

Edited By Dusty on 09/05/2010 19:39:00

Edited By Dusty on 09/05/2010 19:40:14

[JC]

Cheers Dusty

 

 I know that you can't paint directly on to the wood. I did not phrase the question well. The second link you sent answered my question. I had not thought about the obvious, giving the model a coat of Dope. I realyy must think before posting.

 Having started to recover the P51 I realised that it would look better painted. No matter how carefull you are film looks like film.

 

Thanks mate

 

Jon

 

[Terence Lynock]

Wilkinsons market a own-brand sealer for MDF which works great on Balsa, it is less than 4 quid for a half litre can and dosnt raise the grain unlike water based sealers.

It smells like it has some sort of chemical dryer in it and is quite watery so penetrates well, a half litre can will last a long time,

 

regards,        Terry

[andy watson]

The first thing to do is to apply a sanding sealer.  This will prevent the water in the paint causing the balsa to swell and causing the grain to stand out.

 

The surface can now be painted on, but in truth it still isn't really smooth enough for a good finish.  Depending on the type (and size) of model you need some kind of varnish.coating to act as a good base for the paint.  If it is a big model then most people go for glass cloth for strength, with an epoxy resin coating.  I have had excellent results using a polyureathane "varnish" called poly C.  There are plenty of alternative varnishes available- and balsa is pretty forgiving.  The forum has all kinds of things that people have used.  The simple truth is the paint finish can only be as good as the surface it is put onto.

 

Applying the paint isn't easy, even with a good base.  Brushes leave brush marks, I have heard of rollers being used, but I tried it once with very poor results.  I now use a spray gun and a big compressor.  This gives an excellent finish, but is expensive if you just want to do the odd model.

[Former Member]

[This posting has been removed]

[Myron Beaumont]

Cellulose dope with talcum powder added is the best for grain filling IMHO . It dries almost instantly so doesn't penetrate into the wood too far adding pointless weight . Smells great too !

[Bob Cotsford]

the main reason that I never try to paint straight on balsa is that balsa likes to split long the grain.   Covering with tissue or nylon will not only help disguise the wood grain, but add strength across the grain - in the case of nylon, a lot of strength.

Depending on model size, these days I'd go for lightweight glass cloth and PolyC resin for a strong smooth finish on balsa sheet.   I used it for the first time on my Joker and I'm well impressed with how quick, easy and odour free it was.