WattFlyer RC Electric Flight Forums - Discuss radio control eflight

WattFlyer RC Electric Flight Forums - Discuss radio control eflight (https://www.wattflyer.com/forums/index.php)
-   Scratch and Kit Built Aircraft (https://www.wattflyer.com/forums/forumdisplay.php?f=29)
-   -   Covering and Finishing R/C models- A Primer (https://www.wattflyer.com/forums/showthread.php?t=51697)

Sky Sharkster 11-20-2009 02:37 PM

Covering and Finishing R/C models- A Primer
Hello All,
The question of "What should I cover my new model with?" comes up pretty frequently here. Since there's a mind-boggling variety of materials and brands available I thought it might be a good time to gather the recommendations, links and info in one place. If you just want the links without the talk, go here and scroll to "Coverings";
For weights, brands, How-To's, and threads.
The first topic will be the most widely-used material;
Iron-On Films.
Iron-on films have been around since the 1960's, the first (I believe) in the US being Top Flite Monokote. These are thin plastic or polymer sheets with a heat-activated adhesive backing. Generally sold in 6' foot rolls that are 25" to 28" wide, most come with a clear backing sheet to protect the adhesive. The backing sheet must be removed before use. Prices range from $8.00 to $20.00 per roll.
They are applied with a "Sealing iron", a shoe-shaped heating iron with adjustable temperature control. Most quality irons have a teflon coating to avoid scratching the material. A thin cotton "Sock" is sometimes used for the same purpose. The film can then be heat-shrunk tight with (either) the iron or a heat gun.
Since then many other brands and types have appeared, but for our purposes we can divide them into three general groups.
Micro or Ultra Light iron-on films.
The "Micros" are a fairly recent addition to the field. Used mainly for small models, they have the lowest application temperature, are thin and light and come in a limited array of colors. They are temperature-safe for balsa and foam models. Brand names are MicroLite, So-Lite + Nelson Litefilm. Weight is about 1.9 to 2.5 grams per square foot. The Micros have a good adhesive, shrink well, are easy to apply and are fairly strong in puncture-resistance, although not as durable as the thicker and heavier films. The colors may fade over time from exposure to bright sunlight. Used for models up to about 1-1/2 pounds (780 grams) RTF weight and 400 square inch wing area.
Foam-Safe or Mid-Weight iron-on films.
Soon after the introduction of Monokote, it was discovered that the application temperature of the film was too high for foam models. It would melt or bubble most common foam material; If the iron was turned down to a safe temperature, it didn't activate the adhesive properly.
Next, manufacturers filled the void with lower-temp films; "Foam-Safe" iron on's. Top Flite introduced EconoKote, soon we saw UltraCote, Solarfilm, Polycote, TowerKote and several more.
Foam-Safe's come in a wide range of colors (although not as many as the heavier films), are easy to apply and have a good, but limited, shrink rate. They are more puncture-resistant than Micros, but are not quite as strong as the heavier films. For models up to several pounds, material weight 3.0 to 5.5 grams per square foot.
Full Weight or Standard iron-on's.
The "Heavies". Most famously, MonoKote, WorldTex, SIG AeroKote, Coverite Super, Coverite 21st Century, Glosstex. By far the widest range of colors; transparent, metallic, pearl, military flat, checkerboard or pattern, florescent, frosted. Thickest material, highest application temperature, not safe for foam. Easy to apply, will mold around compound curves well, highest shrink rate. Will easily warp or crush light balsa structure while shrinking. A few have a textured or "weave" finish to replicate fabric-covered surfaces. Material weight 5.0 to 13.5 grams per square foot. For use on the largest size models.
Here is a good photo and text tutorial on covering with iron-on's;
There are many other types of covering materials and finishes. I'll add more information soon, in the meantime, any tips, comments and links will be appreciated!
Hope this is helpful,

buzzltyr 11-20-2009 03:42 PM

Ron, I'll be keeping up with this thread, for sure. You are a great builder, so I'll be interested to see what you have to say and recommend. Are you going to cover (no pun intended) some of the other materials/methods, such as tissue and dope, or polyspan? I have even seen giant scale models covered with Ceconite, the stuff they use to cover full size planes these days. So the choices available to us are huge, to say the least.


Sky Sharkster 11-20-2009 05:41 PM

Covering More?
Hi Mark,
Thanks for the kind words, hopefully some of the Members who are familiar with other methods will post here.
I'll go over some of the material I've tried like LiteSpan + CoverLite and WBP over silkspan. There's lots to choose from!

pd1 11-20-2009 09:08 PM

Silk anyone?
6 Attachment(s)
Working with silk.
Silk is a natural fabric It is woven and will cover around compound curves very well.
I've covered foam planes with silk, and balsa too.
This will be about covering open areas of a balsa structure or a solid sheeted area.

First prepping the wood.

Balsa is cellulose based and it absorbs colored dope/paint like a sponge.
The faster you can seal the pores of the balsa, the less coats of paint you will need.

Dope, both clear Nitrate and butyrate, fills the pores in balsa well and stops the wood from sucking up paint.

The better the finish of the uncovered wood, the better the overall finish will be.
A few coats of clear will seal and then start to fill the grain of balsa.

Some people add talc powder to the dope so it fills the grain a little faster.
Some use a product called sanding sealer to fill the grain rapidly.

I prefer thinned dope. Thinned dope fills pretty fast and doesn't get too thick over the high spots.
Then I dry sand with 180 to 220 grit sandpaper using a block to get all the high spots down.
The goal is to get an even smooth surface, before you cover.

A lot of people use nitrate dope for the first steps.
I feel butyrate works just as well.

But remember nitrate and butyrate are not the same.

Nitrate can't be applied over butyrate. It will react and ruin your finish.
Nitrate is very flammable compared to butyrate.
Nitrate has a little better adhesive qualities compared to butyrate.
Nitrate requires additional fuel proofing.If your plane is to be glow powered.
Nitrate stops shrinking after a couple of days.
Butyrate shrinks for a long, long time.


Since I don't use nitrate anymore, This will be using butyrate. The proceedure for Nitrate is the same.
To increase the adhesiveness of the butyrate I coat the bare structure with butyrate until the wood picks up a shine after the wood has been sanded smooth.

The brush.
I like a 3/4 inch wide camels hair brush. These are available from hobby or craft shops.
Some people have had good luck with the foam brushes. I like the foam brushes for paints other than dope.

Applying silk to an open structur

Lay a piece of the dry silk over the area to be covered.
Silk has a grain to it. The grain should go spanwise.
If you put the silk on so the grain is chordwise the silk will pull down between the ribs and look odd.
Silk shrinks greater with the grain than across the grain.
The grain is usually the side with the edge finished from the factory.

Wetting the silk with water
I use a small atomizer to wet the silk.
Keep the silk wet, I mean really wet.
It will stay put just from friction if it's wet.

I use a lot of thinner with just a little dope to stick the silk.
The thinner passes through the silk and softens the dope underneath sticking the silk down.
If you accidentally get some of the thinned dope on the silk, there is not enough dope to curl the silk.
Thick dope will curl the silk as it drys.

Using dope while the silk is still wet will cause the dope to blush
. It will actually turn white.
Let all the water dry off the silk before doping too much.

Avoid days with high humidity

If it is a day with high humidity, the dope may blush again. A couple of drops of retarder will stop that.
Sig sells retarder in small bottles.

A couple coats of dope on the silk over the structure helps to bond the silk to the balsa.
Do that before trying to fill the weave of the open areas.

There are many ways to stop dope from dripping through the silk.
I like the thinned dope method, it always works.

When filling the weave of the silk, use cross coats.
One coat chordwise followed by one coat spanwise.
I usually do this to each wing panel before going to the next panel.

Avoiding the drip through.

When doing open wing panels, just use very thin dope and hold the surface vertical.
If you hold a wing horizontal while doping, especially with dope that hasn't been thinned a lot, the dope will drip through and make an ugly ''ring'' on the other side of the wing.
The thinned dope will not leave a ring, and if the panel is vertical the dope will stay on the side you are doping.
The newer silks have a much tighter weave than the old silks. The new silk fills a lot faster.

If you've been using nitrate dope, this is a good spot to switch to butyrate.

On the last couple of coats of clear I add a couple of drops of Castor oil to the clear dope. It will act as a plasticizer and will slow dope from drying out over a long time.

Silk source.
I've found that there are at least two different silks that shrink different from each other.
The silk from Thai silk seems to be pre shrunk and doesn't shrink much if at all after covering.
This is good for delicate structures. Or over solid sheeted areas.

Non shrinking silk


The silk I like from there is the 5mm 021F-000 Habotai.

If you want silk that shrinks more, the silk from Dharma Trading is for you.
It's great for stronger structures or open areas like wings.

Shrinking silk


I use the 5mm. HS536 or the HS545 same but 45 inches wide.

I've found the 5mm silk is lighter than any other covering, including tissue and the weave is so tight that it doesn't take much clear to fill.

Before you ask,mm is not milimeters. ''MM is Momme.
Momme (pronounced ''mommy'' and abbreviated ''mm'') expresses the weight in pounds of a piece of material of size 45 inches by 100 yards. So, for example, a 50 yd. bolt of our 5mm 45'' Habotai Silk fabric (#HS545) would weigh 2.5 lbs. (plus the weight of the cardboard tube it is wrapped around, of course).
The higher the momme, the heavier and stronger the fabric. Anything above 28 momme is considered heavy-weight and generally used for curtains or heavier outer-garments. Silk under 20 momme is considered lightweight, and generally used for light blouses with a chiffon feel. Medium-weight silk (20 to 28 momme) is excellent for silk scarves, furnishings, wedding dresses and the ultimate luxury of silk sheets.'
' Dharma Trading.

5 mm silk is extremely light.
A sheet 45 inches wide by 300 feet long would only weigh 5 pounds.

Drying out and rot.
Unless you leave the silk in direct sunlight, the silk won't rot.
What actually happens over time the dope becomes hard and brittle. The silk is saturated with the dope and when the dope cracks, so does the silk.
I just started removing silk that was applied 40 years ago. The silk is fine, the dope isn't.
If you plan on leaving your plane in the sunlight for storage, a couple of coats of silver will stop Ultra Violet damage.

Dope to thinner ratio, I find I use twice as much thinner as dope.

Colored silk
It seems that silk only comes in white lately. Colored silk over an open framework with just clear dope is a nice light finishing technique.

It is easy to dye silk.

Now to the color part.
I've been told ,"you can't dye silk without a special process".
Once way back when, I tried with the little packages of Rit dye.
I made a mess and the silk was all streaky and not colored evenly.

I read the process at Dharma and it basically told of a long and involved procedure to color silk.

My wife said,"try this". She handed me some new Rit liquid dye, and an old pot.
When I finally got up the courage to try it, I was amazed.
I didn't make a mess and the silk took the dye evenly through out.
All I did was follow the instructions on the back of the package.

Basically add the liquid to hot water and let simmer on the stove.
Add the wet silk and stir for thirty minutes.
Rinse with cold water and wash with some detergent, let dry.

The next day wash again with a mild soap or detergent. It seems the excess dye doesn't go away completely with the first wash.

Failure to do the second wash will result in the excess dye transferring to the clear dope by way of the brush and mixing together, and contaminating the clear.

Also when you go to add colored dope over the dyed silk, the color will bleed through to the surface.
Darker colors are harder to cover over.
Red is the worst.

Sky Sharkster 11-21-2009 12:42 AM

Great Post!
Wow, Thanks, Paul. That's as good a tutorial as I've ever seen, should be a big help.

pd1 11-21-2009 12:51 AM

Finishing foam planes.

The foam planes can be painted directly with artist water based acrylic paints or Krylon h2o paints and house type latex paints.
Some Tamiya and Testors spray paints

All of the above will color the plane but will add no strength.

Covering the plane with fabric or paper adds to the overall strength of the plane.
Some people have used brown paper, silkspan, fiberglass cloth, and silk.

Others have use Solite or Towercoat films , iron on and your done.

There are as many methods to attach the covering as there are modelers.
Some use spray on contact cement, some epoxy, some water and white glue mixture.
And water based polyurethane.
Also known as Min Wax poly.

My choices for a good finish are silk and Min Wax(wbpu).To remove the bumps and dents I fill them with pre mixed Spackle. it's a joint compound for filling dents in walls.
I like the DAP brand, it goes on pink and when dry it turns white.
It can be bought in small resealable containers and it sands easily.

After applying the Spackle I sand the surface as smooth as possible.
I prefer minimal filling, I leave the super finish for others to do.
I coat the spackled surface with a coat of wbpu and when that's dry I add silk.

I use a cheap foam brush to apply the wbpu to the silk. I start in the center of the area to be covered and work outward removing wrinkles as I go.

After the first coat is dry , I trim all edges and add a second coat.
After the second coat I lightly sand with 320 paper.

The I add some type of primer base.
I use the craft store acrylic paints now.
I like grey for primer.
I mix them 50 % with water and spray.
Two coats and it's wet sand time, get the area as smooth as possible and try to get all the areas to be scuffed by the sandpaper I use 400 wet for this.
Once all the weave is full and smooth, I spray the final color.
First coat I sand again till very smooth, next coat I only lightly sand.
Add trim and a final spray coat or two of MinWax.

For great painting tips read the next post by Grasshopper.

Sky Sharkster 11-21-2009 05:36 AM

Non-Adhesive Iron-On's
10 Attachment(s)
The next type of covering we'll detail is the non-adhesive iron-on. This covering looks very much like doped silkspan or tissue when applied, has a translucent finish and may be clear coated, color painted or (the first two products listed) left uncoated. These coverings do not have an adhesive on the back, they are applied by brushing a heat-activated adhesive directly on the framework, then applying the material in the same manner as other iron-on's, that is, with a sealing iron. Since there is no adhesive on the back of the material, seams, joints and any additional pieces must have a thin line of adhesive brushed on top of the join line of the bottom layer, so the next layer of film will adhere. Once applied, the material may be heat-shrunk in the usual way, with either a heat gun or iron.
LiteSpan + CoverLite
These are basically the same product, one is re-packaged and renamed for the U.S. market. http://www.solarfilm.co.uk/aboutus.html
It comes folded in a packet, the sheet size is 36" x 19.5". Color selection is 9 different colors, price about $7.00 per pack. There are two products made for use as an adhesive, Stix-It from SIG Mfg;
And BalsaLoc;
I have also had some success using Minwax Poly as an adhesive (see photos).
Weight is between 2.5 and 2.8 grams per square foot, without adhesive.
I have used this covering several times and can say it has a beautiful look to it, much like an "Old Time" doped finish but much stronger and more puncture-resistant. It does take some time to apply, since every join line and seam must have a coat of adhesive applied. I would describe the molding ability around compound curves as average and it doesn't have the great shrinking rate of some other films, it must be applied fairly taut and wrinkle-free. It can be clear-coated with most hobby paints and Minwax WBPU. It can also be color-painted, either with a brush or an airbrush. I've included a few photos of Litespan/CoverLite finishes.
Polyspan is a polyester tissue material that does not have an adhesive included. It can be applied using Stix-It, BalsaLoc or clear dope. It only comes in white, but can be colored by adding a concentrate to the clear dope topcoat, or by painting. It is not made to be used without a topcoat, it is porous and needs to be filled with dope or other clear coat. It cannot be dyed, the material is waterproof. Rolls are 20" x 12' and cost $15.00. Starline also sells the liquid coloring concentrate in red, orange, yellow, blue and black, $5.50 for a 2 ounce bottle.
Here is an article by Don Typond on Polyspan;
Finished weight (according to Typond) is 3.6 grams per square foot, including 5 coats of 50/50 nitrate dope/thinner.
Hope this is useful, thanks again to Paul for his contribution! Anyone having experience with other covering methods or material, please feel free to add to the thread.

Sky Sharkster 11-21-2009 01:54 PM

Covering Weights - Practical Numbers
Here's some numbers to help calculate your next covering job weight.
This is a link to covering weights;
We'll start with a typical "400" sized model and cover (just) the wing, the largest single component. Since weights are given in square feet, we'll use an easy size, 2 square feet, OK?
1 square foot = 144 square inches, 2 square feet = 288 square inches.
Models having a wing area of (about) 2 square feet;
GWS E-Starter 265 sq in
Mountain Models Switchback 265 sq in
Mountain Models Dandy Sport 300 sq in
StevensAero SQuiRT 260 sq in
StevensAero G-Ride 260 sq in
That should provide a good mental picture of 2 square feet. Since we're covering both the top and bottom, we need 4 square feet of covering.
First, a "Micro" covering like SoLite or MicroLite;
2 grams per square foot, 4 square feet= 8.0 grams
Next, Litespan/CoverLite material weight, without adhesive or paint;
2.7 grams per square foot, 4 square feet= 10.8 grams
A foam-safe transparent, UltraCoat Transparent; 5.0 grams x 4 = 20.0 grams.
More Foam Safe coverings. EconoKote, TowerKote + SIG AeroSpan are about 5.6 grams per square foot, X 4 = 22.4 grams
MonoKote, UltraCote (opaque), Coverite, PolyCover, AeroCote (regular) have a range of 5.9 to 13 grams per square foot. Let's try an average of 7.5 grams per square foot. 7.5 grams per square foot x 4 = 30.0 grams.
So, for a 16 ounce model, where we're trying to save a gram here and 2 grams there, the difference between Solite and EconoKote is 14.4 grams or 1/2 oz.
Between MonoKote + SoLite is 22.0 grams. Just for the wing.
I'd guess at least another square foot to cover the tail and fuselage.
Some numbers to think about!

av8djc 11-21-2009 03:51 PM


Excellent write up! I've done a lot of dope work on models and full size airplanes and I still got some good pointers from your writeup.

What weight silk would you use for 1/4 scale aerobatic planes like a Pitts Special? In AZ we have little grass and fly off dirt or as they call it Granite which is a fine gravel of about 1/4" and a lot of fines. The little buggars do get thrown up though and puncture film coverings. My old favorite, Super Coverite, holds up great yet I'm looking for something lighter. Without having an adhesive coating on all of the fabric it can be lighter with silk right off the bat I would think.

Also I guess I could do the bottom of the wing (or lower wing) and the bottom of the fuselage with a heavier silk and use lighter weight on everything else?

Grasshopper 11-21-2009 04:14 PM

Air brushing and painting
15 Attachment(s)
Nice thread Ron,

Another area that usually gets a lot of questions is painting. Although I'm not that good at it, I like airbrushing with acrylic craft paints. They are cheap, readily available and easy to use. About the only thing that limits you is your imagination.

I try to stay away from the Krylon H2O paints as I think they go on too thick, are heavy and don't cover all that well. There are water based paints made specifically for airbrushing and they work great out of the bottle. They are a little more expensive and don't have quite the variety of the cheap craft paints either.

Of course preparation is the key to any good paint job and is the most time consuming. I usually spend a lot of time filling and sanding before the paint goes on. Planning your paint scheme ahead of time usually helps as well. I typically know what the paint scheme is going to be before I even start the build. You should also plan your decals at the same time. (Decals can be an entire subject in itself).

Once the model is covered, I like to sand it lightly with 400 grit paper. I usually use it wet if the model allows it. After sanded and dried, wipe it down with a dry cloth then a tack cloth to remove any dust.

Attachment 113788 Fuselage sanded and ready for primer.

When setting up to spray, I strain the paint through a paint strainer and thin it with water about 1/4 water and 3/4 paint. This is not critical and can be thinned up to 1/2 with water if needed. Some suggest to use windshield washer fluid. I personally can't tell much difference so I use plain tap water. You just have to play around with it to get the consistancy you like. I usually set my air pressure to around 20 to 30 psi. I always practice on a piece of cardboard or large sheet of paper before actually shooting the plane. You want enough pressure to spray the paint out evenly but not so much that it makes the paint blow around on the surface. You also need to have the paint as thick as you can get it so it flows evenly out of the nozzle but not so thick it clumps up or splatters out of the nozzle. Again, this is just something you have to play with.

Once your air brush is set up and you've tested it, it's time to shoot some primer on. I don't always use primer but it's usually a good idea, if nothing else but to get an even coverage with the top coat. If you're painting on white foam, you may not need primer.

I just use gray acrylic paint for primer, shoot on a nice coat, let it dry, hit it with a second light coat, let it dry completely then wet sand it all again.

Attachment 113789 Primed and sanded.

After it's been sanded again, go over the entire plane with a tack cloth a second time. Now it's time to shoot the colors. This is where you need to do some planning on the order in which they go on. Always shoot the lightest color first and work your way to the darker. You should also have some hangers ready to hang the parts on so they can dry. I use pieces of bailing wire hooked to my garage door tracks. Do a test hanging of the parts and have the hooks ready before you start to paint. The last thing you want is to have your wing covered with wet paint, then remember you have nowhere to hang it.

On this Hurricane, the lightest color is the light blue on the bottom so that's the first color. Spray one light coat, let it dry then spray the second coat. Remember, light coats are much better. Don't try to get it all covered at once or you won' be happy with the finnish.

Attachment 113790 Bottom of plane painted light blue.

Let the paint dry completely. Paitience is king when painting. I know it's tough when you're down to the end and want to see the finished product, especially after slaving for months over the build but the last thing you want is to botch a paint job after all that hard work.

The top colors are a little more difficult since there is a camo scheme on this one. For me, painting a camo scheme with blended lines is much easier than some of the schemes with hard lines that have to be taped. If you do have to tape, MAKE SURE the paint is completely cured before applying tape. This could mean waiting days between colors to make sure the paint can handle tape without pulling it off. I like to use the purple colored low tack painters tape. It's not as sticky as the blue and leaves a nice clean edge. Either one can pull up the paint if you're not careful. Masking can be very time consuming. This funjet had hours of marking and masking with probably a total of only 15 minutes of actual painting time.

Attachment 113791 Multiplex Funjet

So now, you can shoot the lightest of the two top colors. I chose a paint scheme that had blended lines instead of hard lines so I didn't have to mask anything. You do need to be very careful of over spray getting on the lighter colors so pay attention to the direction your airbrush nozzle is pointing.

After the lighter base color is on, you can shoot the top color. For some reason, the colors in this picture came out weird but you get the idea on the paint pattern.

Attachment 113792 Top colors on.

OK, so the top colors are on. Now is when I will let it cure for a day or two, check for any areas that need to be touched up or over spray covered then hand paint any details like the canopy, exhaust stacks, etc. After that, you can apply the decals. Once the decals are on, I like to give mine a coat of Minwax Polycrylic Satin finish for a nice clear coat. I use the satin so it's not shiney. The clear coat will also bring out the color in the other coats, and give it a finish to help make cleaning easier. It also helps keep finger prints off the flat paint. The top coat will make the decals have the same finish as the rest of the plane so you don't have shiney decals on a flat paint scheme.

Attachment 113793 Attachment 113794 Attachment 113804

Painting with an airbrush is really not that difficult. It just takes some practice, a place to do it and a lot of paitience. The results are very rewarding and you can get a lot of paint schemes and apearances that can't be done with rattle cans or brushes. Another thing to keep in mind, is you need to keep your airbrush clean. I completely clean mine after every color I put on. My brush is several years old and there is not a spec of paint on it. It looks as good as it did when it came out of the box.

Have fun, be creative and go for it!

Attachment 113795 Attachment 113796 Attachment 113799 Attachment 113800 Attachment 113801

Attachment 113797 Attachment 113798

Sky Sharkster 11-21-2009 05:00 PM

Questions + Answers
To Grasshopper;
Thanks, Tom!! Great post, makes me want to build a model just so I can airbrush it. Oh, wait, I don't have an airbrush....hmmm., Wonder how much it would be to ship a model to you? Hmmmm.
To Av8djc,
Hi Dave,
I'll have to defer to Paul or other informed Members for your questions, I'm no expert on silk and dope. My last silk covering job was way back in the 1970's, a Free Flight A.2 Nordic glider. Can't remember the silk weight but it was very light. Hopefully you'll get an answer soon. Thanks for the kind words, hope this thread is useful.

Bub Steve 11-21-2009 05:27 PM

3 Attachment(s)
HoppyBub's the Best model finisher I've seen and am proud off the 109 (seen in pixs) he gave my youth club, Everyone makes coments on the finish (not on my fly'in unabiltys )bubsteve


pd1 11-21-2009 06:49 PM

Dave, I personally like 5mm silk. I have it on an Aeromaster that's 7 pounds and it holds up well. It's not 1/4 scale though.
But if you are concerned with foreign objects being thrown up, 8mm would be a lot stronger.

Way back when... we used to cover our planes with nylon.
Nylon cost less than silk and was strong enough to not tear when landing without landing gears.
Matter of fact it didn't tear when the plane crashed either.
Maybe you might try some nylon and see how that works.


av8djc 11-21-2009 10:18 PM

Originally Posted by pd1 (Post 663558)
Dave, I personally like 5mm silk. I have it on an Aeromaster that's 7 pounds and it holds up well. It's not 1/4 scale though.
But if you are concerned with foreign objects being thrown up, 8mm would be a lot stronger.

Way back when... we used to cover our planes with nylon.
Nylon cost less than silk and was strong enough to not tear when landing without landing gears.
Matter of fact it didn't tear when the plane crashed either.
Maybe you might try some nylon and see how that works.


Thanks. I don't remember for sure but does nylon shrink with an iron like the dacron? When the time comes I'll order some of the 5 and the 8mm silk.

hillbillynamedpossum 11-22-2009 04:55 AM

my two cents:

Im not even close to the builder that Paul is.....I have covered several planes with polyester dress liner. You can shrink it with an iron and the stuff draws up drum tight. I start by giving all the surfaces that will touch the polyester about 3 coats of thinned nitrate. Then I usually tack the corners with c/a and dope down the edges with nitrate dope thinned about 1/2 or 1/3, wait for the dope to dry and shrink away.

give the dress liner two coats, sand with 400 grit then 2 more coats then sand with 400 or 800 grit and then its ready for Buytl dope.

One note, you have to use nitrate with polyester, because butyl wont bond it.

on a side note.....How bout a post on covering and shrinking saran wrap? I just did my first wing in saran wrap today, and I didnt take pictures....DOH one wing looked good and I managed to melt a hole in the other....RATS Theres got to be someone better at it than me!


hillbillynamedpossum 11-22-2009 09:48 PM

Covering with Glad wrap
16 Attachment(s)
I must have Scottish ancestry. My wife says Im as tight as the bark on a hickory tree. Im always trying to make things stronger lighter and mostly, CHEAPER. This is about as cheap as I can get. Glad wrap as covering....about $4 a roll. Its great for show-off static planes and according to some folks, it flies pretty well. Im waiting on some guts to make the plane in the pic go weeee....ordered them yesterday from Jeff, so Ill have them by tuesday. By thursday my little balsa bird will be splinters.....I LOVE IT.

The first pics show a hole I melted into the skin, and a patch I made on it. It would have flown ok, in fact it flew great as a glider, buy my vanity made me want to redo the wing and make a thread on covering using glad wrap. Here goes....


Sky Sharkster 11-23-2009 01:16 AM

Covering Temperatures
Hello Possum,
Thanks for the post and photos, that's a clever way to cover a model!
Now we'll move along to iron-on temperatures. Here's a link to the Coverite recommendations for a few popular films;
As you can see, they recommend a lower temp for attaching to foam, higher for attaching to wood and higher still for shrink. This (using the iron) is my prefered method for shrinking, since it's way too easy to melt coverings with the heat gun. Another problem with the heat gun is what I call "Ballooning", that is when the material puffs outward because too much heat is trapped inside the structure. A few pinholes around the perimeter can help release the hot air. but sometimes the gun stretches the material out before it can release, resulting in wrinkles when the material cools.
So, try using the iron. After a structure is completely covered, go around the edges and seal off any loose ends, joints, overlaps.
Then turn the iron up one or two clicks and begin "Waving" it over the surface, an inch or so above the covering. Keep the iron moving and just chase the wrinkles off to an edge or corner.
With wing panels, I like to rotate the wing top-and-bottom, shrinking a few rib bays on top, then the same section of the bottom. This helps eliminate warps and twists.
Here's a link to the Ultracote covering temperature settings and covering tips;
And one for SolarFilm Products- Click on "How To" then "Instructions";
Here's a MonoKote "How To";
Last, books on covering models, most by Randy Randolph;
Hope this is useful!

pd1 11-23-2009 01:30 AM

Possum, you can get that Glad Wrap in green and red too.

hillbillynamedpossum 11-23-2009 01:53 AM

Thanks Paul, I only have access to what my wife brings home from the grocery store



Thats pretty much me at the store....


Sky Sharkster 11-27-2009 01:46 PM

Covering A Wing With Iron-on
10 Attachment(s)
Hello All,
Here's a photo step-by-step of a wing covering job, this is my micro Corben Super Ace. I first posted this on the build thread, but thought it might be useful here. The covering is MicroLite, but the method should apply to any material. Only the iron temperature will vary.
I like to use a new sheet of poster board as a mat, the shiny side; Nice straight cuts with no jagged edges. A straight edge ruler, 90 degree triangle, scotch tape and lots of new # 11 and single-edge blades. Once they start to snag, use another new one. The old ones can still be used for balsa and general work.
Clean the bottom of the iron. The colored adhesive can bleed out, discoloring another color of material. Make sure the wood (or foam) structure is smooth and dust-free. No bumps!
Start with the lightest color material first.
The smoother (no wrinkles) you lay the material on before and during ironing, the better the final job.
Here's the bottom covering job, the next post will be the top, in two colors of material.
Good Luck!

Sky Sharkster 11-27-2009 01:57 PM

Top Of Wing
10 Attachment(s)
Here's the top of the same wing. I used yellow for the rear and black for the front. The overlap is on the spar, a 1/8" wide x 1/16" thick balsa piece. I cut all the pieces to (rough) size first.

birdDog 11-27-2009 09:58 PM

Unsupported seams?
What do you guys think about unsupported seams?
I am using Coverite Microlite and am making the seams on the workbench. I am using 175-180* (as stated as the lowest adhesion temp) so that I do not disturb the backing too badly (seems to cause bubbles).
Anyhow, I am overlapping about a half inch. I can see that I have evacuated about 99% of the air.

Do you think the heat gun (I know Ron, you like the iron, but I am stubborn:rolleyes:) heating the covering to shrink is enough to set the seam fully or am I asking for trouble? :o

Sky Sharkster 11-28-2009 12:23 AM

Tough Call
Hi Rob,
Well, I wish I could help you, but honestly I've never tried unsupported seams with MicroLite. I have with heavier films and it never works out.
They either pull apart while shrinking or pucker so badly (since you need a wider overlap) that I gave up trying.
However, with a 1/2" overlap you might be OK. If they're fully stuck together they may shrink at the same rate. If not, it will pucker and wrinkle. The bottom layer has to shrink as much as the top, or it will pull unevenly.
I can't advise you to use the gun on MicroLite. It's too heat-sensitive and I fear you will melt something. Even a slightly higher temperature with the iron will melt a hole faster than you can say "Yikes!".
But you might get away with it. Be careful!

birdDog 11-28-2009 03:19 AM

I like Microlite!
Actually now that I think about it, I have similar seams (3/8") on last winters build and they have held up fine after really putting that plane through the wringer this year.

I think the Microlite might handle the shrinking stage a little better since it is thinner (allowing better heat transfer to lower layers) and a lot softer (and weaker, only use for parkflyers. Been there, done that).

Seams are pretty tricky though, takes a lot of layout, planing where to remove or leave on the backing so you can seam them on the bench.
A left over piece of backing is extremely valuable for this. I try to use at least 3/8" overlap but more doesn't hurt. The biggest reason I don't just double up the layers for large sections is that I seem to get allot of bubbles between them and hate chasing them around and poking holes.

I have also found that Microlite is hard to work with in the summer or high humidity. It likes to curl up and stick to itself:mad:. Best applications (for me) are in the cold basement since it is such a low temp covering.

cbatters 12-29-2009 12:32 AM

Any suggestions on where to get small pieces of UltraCote?I need a small piece of white to do a repair on a used T-34 I bought. (seems like a waste to buy an entire roll for less than a square foot I need for the repair)

All times are GMT +1. The time now is 12:43 AM.

Powered by: vBulletin
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.

Page generated in 0.05730 seconds with 9 queries