what is the plastic covering on balsa planes?

[chinbqs]

just wondering, what exactly is the plastic material that covers balsa planes?

issit something like a shrink wrap or something.......or its just cellophane paper?

[baby_zyklon]

yes, it is call monokote. Well monokote is actually the brand name under top flite, but most of the time you say monokote people will understand. You stick it on to the balsa and then iron is and it shrinks to tightness, but must stick it well in the first place. A lot of skill involve to cover the whole plane...so best way is to play cheat buy arf

[baby_zyklon]

http://www.monokote.com/monoinst1.html

looks easy, but it really is not. Heck, I even have problem applying trim sheets.

[chinbqs]

then sometimes, i see a plane totally covered in this white material, with a matt surface......like tracing paper liddat...
is that also monokote?

thanks a lot

[baby_zyklon]

paiseh, I got limited experience, don't know what is the matt surface type. Another type is the "cheap china paper" type that comes with super duper cheap balsa planes, but that is also smooth and glossy.

[chinbqs]

paiseh, I got limited experience, don't know what is the matt surface type. Another type is the "cheap china paper" type that comes with super duper cheap balsa planes, but that is also smooth and glossy.

about the super duper cheap balsa planes, do you know where i can get one?

[baby_zyklon]

I got mine from toykar in bukit timah. $99 for low wing trainer.

[baby_zyklon]

opps forgot to say what is it. Its a seagull 40size low wing. Sold it a year or two back.

http://www.daddyhobby.com/gallery/showphoto.php?photo=1750&cat=500&ppuser=151

[joe yap]

Monokote, Oracoverlite and Solarfilm are actually Mylar plastic films, and Oracover and Solarkote are Polyester film. Mylar film has better gloss finishing and polyester are well known for its ability to be stretch and shrink more than Mylar. Some bigger scale planes use Solartex and Oratex, which are heat shrinkable woven fabric, which produce very realistic fabric finishing.

Those white translucent matt paper type of finishing is the most primitive covering, used on the very first type aeromodels. They are either kite or Japanese tissue paper apllied over the airframe with dope

More than a decade ago, the Solarfilm company started to produce a kind of polyester tissue, which is much tougher than the Jap tissue and fully water and fuel proof. Also, it has the same kind of finishing as the Jap tissue and comes in numerous colours. The trade name is 'Litespan' and another company sells something either similar or same by the name of 'Coverlite'.

For those cheap China plastic films, I do not know what kind of plastic material they use as they do not behave exactly like any other brands I ever used.

[chinbqs]

Those white translucent matt paper type of finishing is the most primitive covering, used on the very first type aeromodels. They are either kite or Japanese tissue paper apllied over the airframe with dope

that means i can use tracing paper instead of the expensive monokote to cover my plane?

wah liddat then i can create a low cost "balsa like" plane using just foam as the ribs and tracing paper as monokote!......will it work?

thanks for all your replies

[joe yap]

that means i can use tracing paper instead of the expensive monokote to cover my plane?

wah liddat then i can create a low cost "balsa like" plane using just foam as the ribs and tracing paper as monokote!......will it work?

thanks for all your replies

Not quite. Tracing paper is heavy compared to Jap tissue. Also, it may not shrink properly. In fact, tissue covering one of the most time consuming and difficult task to get it properly done. So much so that when Monokote first appears in the 60s or 70s, it was considered a wonder.

For your information, these are roughly the steps to do tissue covering. First, the balsa wing structure to be covered is sanded down and the frames are painted with a coat or 2 of dope. Next the tissue is cut to roughly 1" oversize of the surface to be covered. Then it is laid onto the frame surface before being sprayed with water. When the water starts to soak into the tissue, it'll cause it to sag and now, you'll have to spread the wet tissue over the frame as tight as you can go, so that all wrinkles are removed. Before the water dries up, paint a coat of dope over the frame where you had painted prevously. The dope will soaked through the tissue and into the wooden frame. When it contacts with the previously coating dope, it'll create a bond which glues the tissue permanently onto the frame.

Now, you have to repeat the same step on the other side of the wing structure, or you may create structural distortions when the tissue dries up.

When the tissue dries up, it'll undo it's sag and shrink drum tight. If both covered surfaces do not shrink evenly, you will be almost certain to get a nasty wing warp.

Okay, now everything is nicely done, but the tissue is not waterproof. So, using the dope again, brush it over the entire tissue surfaces. It'll cause the tissue to shrink even further. Make sure you do both sides together or you'll get the warp again.

After the dope cures, you'll get a very authentic dope and tissue matt white finishing.

Sounds tidious right? This is why many veteran consider Monokote as magic. Now you know why you don't see this kind of covering very often these days, don't you?

The story hasn't end. Tissue covering is fragile and easily torn. After a few years, the dope will become brittle and covering will deteriorate by itself. Not to mention that the fumes of the dope is the cause for headaches and other respiratory problems. The only good thing is that it is very light.

[plug&fly]

Wow.

I can see why joe gets a kick out of doing this all the time, huh Joe? Covering your planes, I mean. Hehehe.

[joe yap]

Of course! Modellors these days are spoilt for choices, and yet still think that Monokote is difficult to do. Thinking back, in those days, modellers took days, if not weeks to cover thier plane. Modellers these days can't even stand ironing film for one day.