life of thinned dope?
 

Could anyone tell me the "life" of dope that's been thinned, how long it stays "fresh" in a closed bottle? If not I'll let ya know in a few days ;) I'm using SIG supercoat, butyrate dope.
Thanks!
Joe

RE: life of thinned dope?
 

It should be Ok indefinitely. Do check the tightness of the top from time to time as the top can loosen up on you and let the thinner evaporate. On the other hand, I have had two instances of Sig Supercoat turning to jelly without an apparent loss of thinner. One was half a 4 oz bottle of clear, the other a half bottle of Stearman red.

Jim

RE: life of thinned dope?
 

Thanks for the reply! I've worked with other kinds of paints & some don't last when they're thinned, like Acrylic. So I was just curious.
Joe
PS That stuff is Lethal! Its as bad as automotive paint. I took my respirator off to take a sip of beer and MAN. No wonder why they call it Dope [X(]

RE: life of thinned dope?
 

Dope is the best while it is still green. Once it starts turning brown it looses its affect and it not nearly as strong......

are you talking about glue?[sm=idea.gif]

RE: life of thinned dope?
 

I have some that I used after 20 years, no problems. I found that it is best to store upside down as, if any leakage occures, it forms a film at the leak and seals itself off.

RE: life of thinned dope?
 

Sorry, but I'm new to building planes. Isn't Dope like a glue/paint type thing? I'm using it as a "paint" for my Donald 4. The instructions said to cover it with, "covering", or dope. Since I'm new to this, I didn't realize the instructions really didn't "go along" with the current kit. The fuseloge, is already "covered". Its a fiberglass fuse, then it was gel coated. So I started sanding, and the realized I didn't really have to sand & cover it. I wanted to paint it anyway, so its not a "bad" mistake. But I probaly should have gone with the fabric covering. Anyway dope, to my understanding , is mainly used for covering the wings, and such with the paper, correct? That's where I get the glue part. Sorry if I sound like an idiot but like I said I'm new to this and its my first kit.
Thanks to all for the help!
Joe

RE: life of thinned dope?
 

Thinned dope should last indefinitely if it is protected from the air. Rodney said it all when he suggested upside down storage. Air is the problem as it lets the thinner evaporate. Butyrate and Nitrate have the same characteristics in this case. Just make sure you use the proper thinner or you will have a bunch of jelly on your hands.

RE: life of thinned dope?
 

P.S. don't discount heat and cold. All paints including dope should be kept at as near room temperature as possible. If you are painting in high humidity nitrate will blush. Blushing appears as a white shade on any color nitrate. When the humidity drops a second coat will correct it.

RE: life of thinned dope?
 

Thanks for the tip ballgunner! Good to know. I don't paint too often in the summer because of the high humidity in Chicago (and its just too #$%^ hot with a respirator, goggles etc). I do most of my painting fall-spring.
Joe

RE: life of thinned dope?
 

As you say, dope is versatile stuff. Clear dope can be used to stick down paper or fabric, to fill pores in wood, etc, etc. and to make a nice shiny surface. Use of colored dope is obvious. Nitrate sticks and fills very well, but is not fuelproof. Butyrate is fairly fuelproof, but takes a while to completely dry and will keep shrinking for a long time. Blushing can be stopped by adding retarder (Sig makes some). I once doped a wing with clear butyrate with retarder outside in a light rain with no problem. Shrinking can be reduced with a plasticizer. Sig litecoat is plasticized to some extent, as are the Sig colors.

Jim

RE: life of thinned dope?
 

Thanks again to all for the replies, here & elsewhere. I'm not done yet, but I thought I would post(try at least) a couple of pics. I think one of our cats, Flash, wants a ridewhen its finished. She likes my Bell 222 also ;) Hope I attached these correctly. I'll soon find out.
Joe