ORIGINAL: Zor
ORIGINAL: Rodney
Please correct me if I'm wrong here but: I've been told time and time again that nothing other than butyrate dope can be applied over butyrate dope. You should always use nitrate dope first to stick down the covering and for the first coats to fill the weave. Once you cover with butyrate, you can ONLY use butyrate for any subsequent coats. Can any of you experts either verify this or correct it if wrong?
I do not consider myself an expert but having quite a bit of experience.
I just wish to confirm by experience that you are correct (since you asked).
Some additional knowledge again based on experience _ _ _
Tautening and non-tautening dope is a matter of degree.
Dope labelled non-tautening actually does some tautening.
Labelled tautening has to be applied to strong structures as it can pull considerably and for a long time (decades).
Nitrate has much better adhesion to wood and fabric so it is used first. Stix-it or equivalent is or can be used for gluing the fabric. stix-it is used after the wood has been sealed wth a couple of coats of nitrate dope.
To spray dope it needs lots of dilution like 50 dope and 50 thinner and very thin coats have to be sprayed to avoid pin holes. Pin holes are due to the thinner evaporating, creating bubbles that find their way to the surface. Thin spray coats can avoid that and so can temperature of the environment.
It is best to spray between 60F and 70F (15C to 21C).
Brushed dope can be diluted only about 10% by volume for easy brushing and pin holes rarely developpe at recommended temperature.
Now someone will post that I am polluting the thread with too much information [img][/img] .
Zor
why spay when a good briush with un=thined buterate goes on and speads out like glass ? save the thinners for cleaning the brush. half the dope you spray will be all over everything down wind of the job. all the dope will be on the airplne when you use a brush!