ksn3n3

Hi, new to the forum, and just getting back into the hobby after a long hiatus. But everything seems to have changed on paint.

looking for advice on what kind or brand of paint to use over butyrate dope on silkspan. Tried Brodak butyrate dope and not happy with the results. Already have several coats of clear butyrate on silkspan and don't want to recover...

Aero gloss out of business, Formula U same, Perfect/Chevron same...

thanks,
Frank

LesUyeda

i'm afraid you are between a rock and a hard spot. Virtually NOTHING can go over butyrate and last. Butyrate continues to shrink forever. and anything you put over the top will crack with time. Randolph was the last dope that I bought, and I don't remember having any problems with it.

Les

p.s. Be aware that there 4 flavors of dope; taughtening AND non taughtening nitrate and taughtening and non taughtening butyrate.

Les

ksn3n3

Thanks Les. I've always used aerogloss which I think is butyrate and never had any problems.
Not impressed with the Brodak. Where can you get Randolph and can you get it in small hobbiest sizes since I think it is meant for full size a/c.

what else besides dope can you use on silkspan?

LesUyeda

I think you can buy straight from Randolph, but I don't think that you can buy smaller than a quart, and if haz mat fees apply, bummer.

I have no idea what the alternatives are. Everything else I know of will weigh a ton.\

Les

speedracerntrixie

My Feedback: (29)

I'm pretty sure that some guys have been putting automotive base coat / clear coat over dope with good success. Usually this is a big expensive hassle and you end up buying way more then you need but there is an easier way. Do a search for a product called Spray Max. It's auto paint that comes in high quality spray cans. The base sprays on like a lacquer but easier and dries to a flat finish. The clear has a valve at the bottom that you puncture to mix the hardener. After that you have up to 24 hours to spray the clear. I have used this system a few times over glassed balsa with great results.

Lone Star Charles

Could you be a little more specific about the Brodak problems? I sprayed Brodak butyrate over some nitrate and got a lot of little pinholes where the fabric crossed the ribs. I just figured that I had not done a good job of filling the weave and that the first two coats of nitrate had soaked into the balsa leaving these holes, but it wasn't my first project and the same applications using a different manufacturer did not have the pinhole problems. I haven't been overly concerned about it, but have probably unfairly stayed away from Brodak since that incident. I would like to hear a little more about your issues.

By the way, I pretty much only use Stits products for my projects now because their line is so complete and very compatible.

chip_MG

My Feedback: (14)

sig stills sells dope..

Rodney

As Les says in post #2 above, NOTHING will go over Butyrate dope except more Butyrate. You can use some things over Nitrate dope but NOTHING over Butyrate will last.

speedracerntrixie

My Feedback: (29)

Guys I beg to differ. Granted I have limited experience with dopes myself but I have consulted a friend of mine that applies Nitrate colors over Butyrate all the time. This guy knows what he is talking about to the point that I am taking my scratch built Dalotel to him for a silkspan and dope finish, not to mention he has won awards at a national level for his finish work. He says that the key is to clean the surface well and to use some retarder in the Nitrate to add some flexibility. As far as the auto type pains are concerned, they have come a long way in the past few years. As cars get more and more plastic body panels the paint manufactures have stepped up to offer paints that are more flexible and easier to apply with great adhesion qualities.. I have used my suggested Spray Max on very flexible fiberglass parts with great results. Pictured is a PT-19 that was painted using Nitrate colors over Butyrate. Cell phone pic that really doesn't do the airplane Justice. I added a few of my last paint work using auto paints just for grins.

ebeneezer3

I've used Randolph's colored butyrate dope on a Sig senior kadet covered with fabric. I expect the smallest unit might be quarts.
In an Air Force fabric shop we sprayed black lacquer labels on control surfaces covered in razorback and butyrate dope

Zor

Any picture(s) available ?

I am curious about spraying labels.

Zor

sensei

Automotive urethane's primers and base coat clear coats systems do work vary well over over a cloth and dope surface, I have been doing it now for 25 years this way on open bay structures, on a few of my builds. From left to right, is my kit built 40% Aeroworks Edge 540, my 27% Midwest Cap 232, my 33% Lanier Giles 202, and of course, my scratch built 70% Staudacher. All these I built and painted back in the early to late 90s with automotive base coat, clear coat over over cloth and dope and the finishes have lasted for decades. The end results always comes down to the prep work, as most things are I guess.

Bob

77chickenhawk

I have always used model master paints the enamel. Then I use PCL automotive bed flat clear over the top. I like model masters because there is a very large selection of colors not only for painting your plane but also doing all the weathering