Butyrate Dope...

There is a company that sells it for aviation .

Is it the same stuff as Brodaks?

In Christ,

If you are talking about Randolph, yes they make the dope for Brodak. The model stuff has a a slightly different formulation (pigments are more finely ground on the colors, slightly more solids in the clear from what I understand, etc.) but it is still Randolph dope.
FWIW: GMA told me he just bought his clear in gallons from the local AC supply house...

Randolph makes the dope, but there is more to it than that. The thinner is different which affects both adhesion and drying times. Brodak dries much quicker than "regular" (call that aircraft) Randolph, and "regular" (aircraft) Randolph thinner, although it will work, is not the same as Brodak thinner. The thinner is the real key (dope starts with thinner, you know) and there is cheap thinner and expensive thinner. Go to an auto paint supply store and you can buy some cheap lacquer thinner to use for cleaning brushes, paint guns, etc. But do NOT use this stuff on your dope. You could use Dupont 3608S (about four times as expensive) to thin your SIG dope, but it has been reformulated. It cost about four times as much as the cheap auto stuff, but worked.

Yes, you can go to your local aircraft supply and buy dope and thinner there. It is not the same as Brodak. It dries slower. It may cause meltdown (slowly eat down into the lower layers) and take a month before you can sand and polish. But it will work.

If using dope, I start with nitrate up to the color coats. Since model quality dope, including nitrate, is not readily available here any longer (One out of three shops stocks a limited selection of SIG butyrate Dope in bottles.), I do use Randolph nitrate and thinner for the majority of my finishing. I have had very good results with it.

I have not tried their butyrate colors or clear for final coats, and, therefore, I won't recommend it. However, if I wanted to continue to finish with dope, a finish with which I am very familiar, and "mpdel airplane" butyrate dope were not available here, I would try the Randolph at least once. After all, those beautiful Bearcats, Mustangs, and Sea furies that Al Rabe flew in yesteryear were finished with Randolph dope according to Al's writings. The finishes on those planes were nothing to sneeze at!

Paul

Before urban sprawl in the Washington DC area, I used to go over to a little private airport near Bailey's X Roads. It was called the Arlington/Fairfax Airport or something (have the name wrong here).

That's where I bought my Clear and thinner, for way less than the Aerogloss or Testor's of the period.

I recall the Clear having a telltale slight brownish tinge to it. But it was still "clear". Pretty thick, it needed a lot of thinner, which made it go even further.

Those days are long gone. Last time I was there, the sprawl was out to Winchester. Currell

I have used Randolphs Butyrate clear dope and Randolphs thinner. Also I have found out that you can use PPG Acrylic Lacquer metallic in brodak dopes to create metallic colors. Worked fine. After two airplanes painted with the spray gun; progress towards better finishes is improving. I feel that you need to add more than one to one lacquer thinner. Probably more like two to one thinner to dope to really put the color on thin and the clear as well to get a good flow and shiny surface.

Bob Smiley

A lancair 360 builder/flyer trying to be a modeler.