stunthanger.com
General control line discussion => Open Forum => Topic started by: Bootlegger on March 08, 2013, 11:27:46 AM
-
Modelers that are using poly span, what do you do when you get wrinkles in the edges that you have doped down?
I know that sanding will "fuzz" the pspan, so how are you getting the wrinkles out?
Any suggestions/help will be 'ppreciated...
-
I've wet it with dope and stretched it and I've cut the wrinkle, wet it with dope and ower lapped it. But then again I'm just a hack. ;D
-
Try using your monocoat iron set on high. I've had great sucess this way, but be careful not to burn a hole in it.
Jerry
-
Both good suggestions Gil. I have used if for a few years now and I guess you do things routinely that you dont think about anymore but I would apply dope to the wrinkle and try rubbing out with my finger then use the heat. I have been known to cut a slit in it and try rubbing it out with dope also. I think it does not wrinkle as bad a silkspan. Usually I do the compound curved tips separately or use silkspan for the tips.
Mike
-
Try using a heat gun to pull the wrinkles out.
-
Use heat first.
If you wind up needing to sand it just cover the sanded area with a small patch of jap tissue. That will take care of the fuzzies that won't absorb the dope.
-
When ever I get to aggresive with the heat gun or iron and get a hole. I cut a round peice out of scrap bigger than the hole and dope it down. After several coats of dope and then primer I can't even find the patch by feel. Then when color is on, can't even see it. But if you do get the fuzzies as they call it, just do about three or more coats of dope before light sanding.
-
Guy's thanks for all the suggestions. I appreciate all the help.
Wasn't there an article about a device from one of the dept stores about a fuz shaver or something like it?
Course I can't find it now...
-
The name of the game is don't get it wrinkled to begin with. PolySpan is not much good for compound curves.
The PolySpan jobs I've done involved a very thorough dopeing and sanding of the wing. I just brush thinner around the edge to get it to stick. Allow at least an inch to wrap around the edges.,
-
I've had very good luck with polyspan by first using several coats of nitrate on the frame. I cut a piece of p'span about 1/2" oversize then dope it down with very thin n. dope, pulling and rubbing it down with my fingers at the edges to get it as smooth as possible. I wait a bit for the dope to dry then at the edges where wrinkles will appear, I use my sealing iron, medium hot, and work it over the edge just like working Monokote by gently pulling and stretching the p-span as I work the iron around the tip or edge. The nitrate dope actually works like heat sensitive glue as the p-span stretches and sticks around the compound curve. To me, it seems to work much easier than silkspan around small, wrinkle-creating compound curves.
-
+1 for Curt
-
I've had very good luck with polyspan by first using several coats of nitrate on the frame. I cut a piece of p'span about 1/2" oversize then dope it down with very thin n. dope, pulling and rubbing it down with my fingers at the edges to get it as smooth as possible. I wait a bit for the dope to dry then at the edges where wrinkles will appear, I use my sealing iron, medium hot, and work it over the edge just like working Monokote by gently pulling and stretching the p-span as I work the iron around the tip or edge. The nitrate dope actually works like heat sensitive glue as the p-span stretches and sticks around the compound curve. To me, it seems to work much easier than silkspan around small, wrinkle-creating compound curves.
Yup! This is the way to handle polyspan. Nitrate dope is a little stickier than butyrate IMHO. You can get around fairly tight curves with it. It's just a matter of working the stuff with dope and heat.
-
Guy's thanks for all the suggestions. I appreciate all the help.
Wasn't there an article about a device from one of the dept stores about a fuz shaver or something like it?
Course I can't find it now...
Don't use no fuzz shaver. Just apply several more coats of dope before a light sanding.
-
Guy's thanks for all the suggestions. I appreciate all the help.
Wasn't there an article about a device from one of the dept stores about a fuz shaver or something like it?
Course I can't find it now...
Gil,
Here you go. "Finally...solution for Polyspan fuzzies." (August 16, 2012) It works very well.
Paul
-
Paul, I sent ya' a P M thanks
-
I've worked with Polyspan quite a bit and what I discovered was when trying to kill fuzz is "Light Sanding" really means Light sanding.
A couple coats of dope over the fuzz, let it dry then just hit it once or twice with 400. All you want to do is cut the threads off that are sticking up out of the dope. Any more sanding than a swipe or two just makes more fuzz.
-
I used (Only on one plane) a single blade razor blade held vertical to scrape (lightly) the fuzzies off. After a coupe coates of dope it looks fine.
Enjoy, Jerry
-
Polyspan fuzzies are usually caused by putting the wrong side of the material "UP". Always make sure you have the SHINY side up and the DULL side down. If you ever put the wrong side up you will know it immediately when you apply the dope. I have done this a couple of times and what you do is wet sand with 400 and this will eliminate the fuzz. I usually put more dope on it before I wet sand it though.
I just coverd the wing to my take apart Ringmaster with Poly Span tonight . Came out really good.
Mike