I'm not good at covering at all, still learning, but our group has covered 4 planes since july all with monocote, and i agree its a pain to stretch but we dont have any problems with our covering, aside from the occasional wrinkle. It has all stuck very well, and of course it helps when 3 people are teaming up on it. I will agree though that the QC on pigments is lacking because it is difficult to get covering that isnt a shade off, when we order we request the same lot # for every color we use. I have too noticed that different colors require different temps, and Bob always uses an iron to heat it on th surface, he rarely uses a heat gun. I know yellow requires more heat than others. these ar pics of three of the latest covering jobs.....

Originally Posted by Jim Woodward

Thaks for posting this. What is your application techique? Are you a "pull, stretch,tack, heat-gun" or a "just-iron-it-down" type of person? Lately I've just ironed it down, as the pull-stretch-heat-gun hasn't adheared properly for me. Also, I sand down, blow-off, and tack-cloth the heck out of the balsa wood.
Jim

I use the same techinique as in the Monokote video "rule of halves" . I do pull the covering quite firmly when I iron it down and remove all the wrinkles as I spot iron it down. Once I have all the wrinkles out of the covering I then shrink with a heat gun. I let it cool for a while, then heat it with the heat gun again to further shrink it and make sure you heat it with a heat gun like you would cut your lawn, back and forth and then back and forth perpendicular to your first try. Once you feall it is completely shrunk, then let it cool again. Then go over it with a covering iron with a enough heat to seal it down and it should in fact stay down.

What a lot of people do is iron it down and then hit it with a heat gun...the heat from the heat gun lifts the covering and allows the covering to "float" on top of the wood. The first time you leave the plane in the sun it will wrinkle. The key is to be sure it is ironed down to the wood and completely shrunken.

here is a great article that I found on this site...I follwo this technique to a "t" and it works great!

This was posted on Flying Giants...it gives a very good idea of how to apply Monokote....

Many have written about applying Monokote. Some of the techniques I will describe may have been previously documented. I cannot keep track of what everyone writes, so I will just state that these are MY techniques that I have found to work very well in keeping Monokote tight. The typical comment I get at the field is “is that paint?” from a less experienced modeler or spectator, to “is that the same Monokote as was on originally on the plane?” from experienced modelers.

Let me begin by saying that the secret, if it is even a secret, is getting the covering shrunk up first and THEN stuck down to the wood. There you go, that is the base of the techniques. I will describe what I do to get it shrunk and stuck.

First, make sure of course that the balsa is dust free. I always use a shop vacuum with the brush attachment. I don’t bother sanding with anything finer than 220. many times, the sheeting is only sanded with 150 grit. It actually might be more like 220 by the time I use it to final sand just because it is worn. And never ever use balsarite.

Some of my friends have experimented with drying their wood prior to covering. The thought is that the wood has some moisture in it and is a particular size when it is of a certain moisture content. And if after covered, the plane is taken out in the sun and some of that moisture is dried out of the wood, then the wood shrinks a little and causes wrinkles. This thought has merit, but I have never done this and I still get very good results. BTW, they shrunk and dried out their wood after construction was complete by putting the plane into a car sitting in the sun. the car was like a oven and supposedly, would dry out some of the moisture in the wood. I don’t do this but thought that it would still be interesting reading.

Sealing the edges:
Of course, getting most of the wrinkles out prior to shrinking is just good common sense. This is simply done using some care and skill in pulling the covering at the edges while tacking it down. After laying down the sheet of covering on the surface. Tack just a spot on one ends of the longer length. Then gently pull opposite of that tack on the other end and tack that spot down. Don’t try to now get the whole edge tacked down. Wait! Go back to the other side at one of the corners and give it a gentle pull. Do not pull real tight, that will distort the covering and you will be screwed. You are just looking to see some of the wrinkles going flat. Now go to the other end and repeat this tack. Now back to a corner, and then to the last corner. Remember, if you pull too hard at any one place, you can actually hurt the process (gentle pulls). Now I will go to the middle of one edge of covering that has not been tacked and hit that with the iron. Now go opposite side of this tack and hit it. Here, you can pull a little harder when directly across from a tacked down spot. I then proceed to go halfway between the middle and the end (1/4) and tack there. Go to the opposite side and tack. Then to the other ¼ side and tack. Not until I have it tacked down at all corners and on the sides at ¼ intervals will I try to completely finish sealing down the edges.

Only seal the edges with ¼” to 3/8” strip of area around the edges. That is all that is needed. Use the edge of your iron to do this so that you don’t accidentally shrink any of the covering. And a trick I use when tacking or sealing an edge is to pull the iron away from the middle of the covering, towards the edge. The iron can shift the covering slightly during the tacking process because the glue is warmed up and soft. So I use the iron to pull the covering tight if it is going to move on me. Avoid going down the length of the covering because you can drag it a little bit and distort the sheet, making it have a wrinkle near a corner. (do I hear some people saying, “crap, I had that happen to me”) so, always pull away from the middle while sealing the edges. If you watch me, you will see me sort of tap tapping down the covering as I pull the iron away and off the edge of the covering. Not too hard of a tap or you will dent the balsa.

Now that we have it completely sealed around the edges, we can begin to shrink.

Shrinking:
Monokote is Mylar. It shrinks very well. Once properly shrunk, it basically stays shrunk. One of the basics for shrinking is to make sure that all of the covering is shrunk. I mean, every single square inch. To do this, we have to sort of mow the lawn to be sure that we have hit every part.

So, I use the gun (never ever use the iron) to start to make slow passes on the covering to start the shrinking process. A good strong light above to allow you to look at the covering reflection is most important to know if you are shrinking the covering. When the covering is shrinking, it will get wrinkly and then go smooth. That is how you know you are doing it right. Learn the right speed at which to pass the heat gun across the covering so that it you see it wrinkle and then shrink.

The reason for the mowing the lawn is that the covering will shrink enough to make it look like the covering is fully shrunk. This will happen before you have passed the heat gun over every part of the covering. And what ever part you failed to shrink, that is not contributing to the full shrink tension.

Assuming now that you have hit every square inch of covering, stop! We are not done. Go take a break and have a coffee or coke(in my case). The covering is going to relax some after the first shrinking. We are going to go back over the whole area again using the mow the lawn technique. But I want to wait for 15 minutes or so to give it a chance to relax. After waiting, do the whole shrink again. I also usually go at right angles to the first passes. You will likely see areas that wrinkle again and then go smooth. That is either a place you missed the first time or the covering re-shrinking some.

What I find is after this second shrinking, the covering more retains the tension and takes a good set. Very important step, do not skip this. And while doing all of this shrinking, do not stick the covering to any part of the structure. We need the covering to float over top of the surface as best as possible so that all of the shrinking is spread out evenly.

Turtle Decks: If the surface is greatly curved like a turtle deck, I will shrink the sides first as I go towards the top. Since if you shrink the top first, it will be pulled down and stuck somewhat to the wood because of the tension. So work up the two sides towards the top and finish the top last.

Sticking down:
Ok, all of the covering is tight and shrunk nicely. You may be tempted to stop here since it will look really smooth. Don’t! we must stick the covering down to every square inch that it touches.

I do this with the heat gun and the sock. This takes a little practice but the technique is to heat a small section of the covering and then push it down to the wood with the sock. You can only work in small sections at a time to keep enough heat in the covering for the glue to be active. When you are successful in sticking it to the wood, you will see the grain in the light reflection. If you don’t see the grain, heat again and push down again. I get a pattern going where I move the gun and swipe with the sock in a fluid motion.

Tip, the wing or whatever you are working on is going to move and wiggle all over the place during this step. I often work in my lap or put the wing on the bench on a towel and use the elbow of the arm holding the gun to hold the wing steady. If you have a helper, that is best. They will simply hold the part steady while you go to work on it. You have to push down relatively hard for this to be perfect and that is where the parts want to move all around.

As you work towards a corner, you may find the covering trying to bubble up. Don’t worry, just push that covering right down into the wood, shoving the gas bubble into the porous balsa wood. Yes, balsa wood is extremely porous and this gas bubble can be eliminated just by chasing it around a little and pushing it into the wood while you stick down the covering. Eventually, there will be no bubble left. Remember no balsarite, that is because this seals the wood and will make it impossible to get rid of the gas bubbles.

So, stick down the covering every where. Don’t miss a spot or it will get you later. When you are seeing every detail in your wood surface, you have got it stuck down. That is why surface prep is important. I don’t bother with really fine sand paper since you can never get rid of the balsa grain. I use coarser paper because I can use it to be sure that you don’t have any seams or mismatched edges. That is what shows up the most. Edge sheeting that is not flush with each other shows up terrible. And it is easiest to get rid of this with slightly coarser paper like 150 grit or 100 grit. A few swipes is better than a hundred swipes.

There you have it, shrink it real good and stick it down real good and Monokote will not wrinkle in the sun and will stay tight for years.

I have to go put up a 100 studs in the basement to get my work shop started. I will check back now and again for any additional questions.

Take care and have fun.
John Battershell.

I get Chuck Norris to persuade my covering to get on my plane.
It goes on and stays on.

All good tips, but the point here is that even after doing the monokote dance and asking Chuck Norris to lend a hand, the monokote still wrinkled up and pulled away as easy as scotch tape...

Originally Posted by CSpaced

All good tips, but the point here is that even after doing the monokote dance....

that's pretty good... the monokote dance...


Does that make the color match from one roll to the next too?

Originally Posted by MattyMatt

that's pretty good... the monokote dance...


Does that make the color match from one roll to the next too?

Matt, Missle Red will never match True Red...

I just got done removing the red from the bottom of one wing. It didn't even stick to the other Monokote on the overlap! Usually you can get Monokote to stick to Monokote without ANY heat. Maybe my trim iron, regular iron and my heat gun are defective.

Originally Posted by MattyMatt

that's pretty good... the monokote dance...


Does that make the color match from one roll to the next too?

Only if you drink some hairspray and add a few drops of 50/50 mix balsarite/acetone in your eyes before picking a roll...

Ultracote has it's shortcomings also. If Ultracote were perfect, we'd all just forget about Monokote and it would cease to exist. Right now, it is the lessor of two evils in my opinion.

I had a roll of Monokote that was 10+ years old. Just for grins I used it on a stab of profile. Although the color was way off, the covering went on even easier than Ultracote, looked great and was stuck permanently.

I'm sorry but those who say Monokote is the same as it was years ago are wrong. I know guys can still work with it (using their bag of tricks like hairspray, balsarite mixed 60/40 with cat urine, stand on your head while stretching it, etc). The fact is, the planes I covered years ago as a beginner look better than the ones I can do now.

Originally Posted by Unbalanced

Matt, Missle Red will never match True Red...

I just got done removing the red from the bottom of one wing. It didn't even stick to the other Monokote on the overlap! Usually you can get Monokote to stick to Monokote without ANY heat. Maybe my trim iron, regular iron and my heat gun are defective.

man... that's not good. The stuff I just used would stick to itself perminatly with just finger heat. Yikes.

Did you contact Tower or Hobbieco? Just curious to see what they said.

Originally Posted by MattyMatt

man... that's not good. The stuff I just used would stick to itself perminatly with just finger heat. Yikes.

Did you contact Tower or Hobbieco? Just curious to see what they said.

Tower sent me a pre-paid UPS lable to ship back what I had left. I have no doubt that Tower will do their best to try and make it right (at least in their eyes). I'm sure they'll send me replacement rolls. Tower has great customer service.
I don't think Hobbico/Tower/TopFlite will even question the quality of their product based on my complaint.

I've got 2 projects going at the moment and had the same problem on one.Hell,I couldnt get monokote to stick to monokote,which is normaly as strong as two pieces of welded steel.Also,when I shrunk it,it pulled loose in all the inside corners.The 2nd project I used coverite balsarite balsa conditioner and so far no problems.I don't know if this was the solution or like you I got a bad batch.Project #1 will also be stripped and recovered.
Siko_flyer
Jeff Sikes.

Originally Posted by Siko_Flyer

I've got 2 projects going at the moment and had the same problem on one.Hell,I couldnt get monokote to stick to monokote,which is normaly as strong as two pieces of welded steel.Also,when I shrunk it,it pulled loose in all the inside corners.The 2nd project I used coverite balsarite balsa conditioner and so far no problems.I don't know if this was the solution or like you I got a bad batch.Project #1 will also be stripped and recovered.
Siko_flyer
Jeff Sikes.

Call up Tower and complain. If everyone that's had a bad roll sends it back to them, maybe they'll admit there is something wrong and fix it. If we just accept it, they're just going to keep selling us junk.

its very possible(obvious) something went wrong during the application of stickum at the factory...Tower or anybody else wouldnt have a clue until this problem presented its self, and im sure they will make it right. And I also think that the issue will be addressed at the factory level, could be just a bad lot, happens occasionally in all industries. I know it sucks to have to RE cover your masterepiece though.

The original or older Monokote adhesive formula was changed not because of them but because of the EPA. Thats why the older stuff still works.
The last time I used it was two years ago, and although it wasn't like the original stuff it worked really good for me.

I have no doubt Hobbico, Great planes are watching this.