Reading the thread about finishing planes movable surfaces before permanently mounting made me think and now I have a headache.  I think I have psted on here before about poly-ester fabric at the local fabric store.   It comes in a wide vaiety of colors.  It is heat shrinkable to a point.  That means you have to put it on as tight as you can get it before doping it.   I have in the past used the iron on adhesives to put it down, which means on over laps you need more adhesive.   I even put it down using butyrate dope.   I don't keep nitrate dope around anymore after messing up a finish one time.  The material itself is a little heavier weave then the Poly-Span material.   To me it also takes less dope to seal.   The yellow poly-ester is on the ISW.  It is also on the stab/elevator.

No comparison.  Silk is the ultimate covering, but for me is too expensive.   For the cost of enough silk to do one plane I can  H^^buy enough poly-ester cloth to cover several airplanes.   Also it has been about 40+ years since I have covered a plane with silk. 

Reading the thread about finishing planes movable surfaces before permanently mounting made me think and now I have a headache.  I think I have psted on here before about poly-ester fabric at the local fabric store.   It comes in a wide vaiety of colors.  It is heat shrinkable to a point.  That means you have to put it on as tight as you can get it before doping it.   I have in the past used the iron on adhesives to put it down, which means on over laps you need more adhesive.   I even put it down using butyrate dope.   I don't keep nitrate dope around anymore after messing up a finish one time.  The material itself is a little heavier weave then the Poly-Span material.   To me it also takes less dope to seal.   The yellow poly-ester is on the ISW.  It is also on the stab/elevator.

If you are familiar with Polyspan, how the polyester compare relative to the % of heat shrinkage.

I am using 100% polyester dress lining. I bought it from 2 different stores and there are differences to watch out for.
First of all I did finish covering the plane I am working on and after some struggles I am very pleased. My airplane sounds like a drum now that the Nitrate Dope is dry. The skin is TIGHT TIGHT TIGHT. But only after NITRATE DOPE.
I bought some (60" wide) for 4$ a running yard at Hancock's, and also got some from Joann's (45" wide) 6$ a running yard.

The fabric from Joann's ended up having noticeably more shrink available. It is a little coarser and stiffer feeling than what I got at Hancock's.
I used MINWAX water based Polycrylic to glue the fabric down. I just brushed it onto the edges, let it dry good, then used my Monocote iron to iron down the fabric. Worked great.
Now the differences.
Turned out to be absolutely critical when covering my control surfaces. They were only 2" wide and I just could not get the rumbled bed look out of them when using the Hancock's fabric. I iron down the edges, pulling as tight as I could, then hit with my heat gun. It would shrink nice and then with in minutes relax and look like heck. So I tried the iron, a low temp, same result. Then started bringing the heat up. I went from bad to worse. So I stripped the control surfaces. I then got Some fabric from Joann's and recovered the control surfaces.It went on reasonably tight.
I covered the wing with fabric from Hancock's and I covered the fuse with some fabric I got from Joann's. I had bought different amounts at different times from the 2 stores. Both shrank OK with the air gun. . The fuse has some open areas and was noticeably tighter than the wings. But both were OK.
It is the small areas (narrow) that I just could not cover tightly with the Hancock's fabric.
To restate the Joann's felt coarse and stiffer but worked good on all parts of the plane.
I do have a build thread an a different site and I did detail covering with 100% polyester dress lining. I will use it again It was cheap and locally available. But man was it a learning curve. But then again it was my first time with the material.
Yes I know my build thread is for a RC not control line, but it makes no deference in covering an airplane what the control is. I hope it helps some one. I sure wish I had known what I have (I hope) tried to pass on here.
My build thread    http://www.rcuniverse.com/forum/m_10675544/mpage_1/key_/tm.htm
The part of the thread that is about covering is on page 2 post #47
Problem starts on page 3 post #59
A second thread I stated, asking for help, is    http://www.rcuniverse.com/forum/m_10751511/anchors_10751511/mpage_1/key_/anchor/tm.htm#10751511
I cold not figure out how to link to individual post, so I hope page and post#'s were not to much trouble.

One thing I should have added is that orientation is also an important factor. Of the fabrics I have used there is more shrinkage with the salvage (length)

How does this dress liner material compare with Sig Koverall?

I think Sig Koverall is easier to use as it has more shrink. And like I said in my first post the shrink of the dress liner materials varies. Sig is going to give the same result each time. If it is at least a some what large area and you use dope (dress liner) will shrink tight as a drum. It is small and especially narrow surfaces that will you fits using give dress liner. I will use Koverall for these small surfaces next time.
I beleive wight and strength are probably similar.
Price wise if you get large amounts of koverall it is shipping that makes it more costly.

Product Code
Description   Price   Type Order
Quantity
SIGKV001   SIG KOVERALL 67 X 26 WHITE   EACH   $5.49   
SIGKV002   SIG KOVERALL 67 X 52 WHITE   EACH   $8.19   
SIGKV003   SIG KOVERALL 67 X 129 WHITE   EACH   $18.99   
 
Now from Hancocks the dress lining was only 4$ a yard and 60" inches wide. That makes it very cheap. My wing is covered with this and is really tight.
Either fabric will not be tight as a drum with out using dope. I prefer nitrate for this. excelent shrink when cured and any seams can be feathered nicely with fine sand paper. But that would apply to both fabrics.
I have decided i will continue to use dress lining but will also use Koverall for those hard to do parts.
Stock up on razor blades, as they are the only thing to trim with. An exacto blade is no good cuuting and trimming these fabrics.
I use a cutting mat and a rotary blade for cutting big swaths of fabric and good scissors for smaller cuts and a little bity pair of scissors for precise work. Ghingers are the best and the most spendy sissors followed by Fiskars.

Any thoughts as applying a silver base for U.V. protection?

Based on my experience restoring antique/classic fabric covered airplanes I'd say that unless you store your models outside all the time it probably isn't necessary.

Thanks billbyles
I had started to gather that also from posting that question on several other sites.
Our models are small enough to always store inside and only see a few hours of direct sun, not the years that full size are exposed to. Also (correct me if I am wrong please) but silver is can be difficult to cover over.
 
Ken

Hi Ken,

Depending on the color used for the top coat, silver can cause funny looking colors.  Yellows get kinda grayish green, etc.

Big Bear

Thanks Bill Little
So it looks like gray primer and then use the paint and color of you choice or use butyrate dope.
We don't need to worry about no stinking U.V.
And thanks DOC Holliday for starting this thread.
I will post additional questions in a separate thread.

Hi Ken,

Silver will cause color distortion, especially with the translucent colors such as yellows & reds.  The way to fix that is to spray a single thin coat of white over all of the silver, and the white coat doesn't have to be perfectly uniform - it can be uneven as far as coverage goes, it is just to brighten up the silver.  Yellows over silver look kind of greenish-yellow and other translucent colors are distorted as well.  If you put the white coat over silver the yellows & reds will just jump out at you.

Thanks billbyles
OK so as I now understand things a undercoat of silver is not really needed for U.V. protection (we fly our planes a few hours a week and then garage them), but will cause us color issues ("distortion, especially with the translucent colors such as yellows & reds"
And as "billbyles"  said in a pm to me (thank you and I hope it is OK that I quote you billbyles here) gray primer under colors won't be much, if any, of an improvement over silver...same problem with color distortion and the colors won't be brightened up the way they will with the white under them.
So looks to me like the way to paint over fabrics (of any type) and silkspan, is Nitrate dope to shrink and then a gray prime like Duplicor sandable primer followed by the color coats and then a clear fuel proof top coat.
Last question on painting       is Duplicor clear fuel proof?
Thanks all

If Duplicolor primer is like automotive lacquer primer I'd be careful about putting it on open bay areas.  Automotive lacquer primers tend to get brittle and the coverings flex quite a bit during flight.  Few primers sand as nicely as lacquer primer but they should be used only on solid areas, not over open bays.

Hi Bill,

For just such a problem, I only spray the Duplicolor Filler/Primer on the sheeting and cap strips.  Works good that way.

Bill

What would be recommended for open bays?

I use clear dope mainly to fill the open bays..  It doesn't take much, usually.  0000 steel wool to "sand" the open bays.

Big Bear