Whats the DEAL with Covering.

[SleepyC]

I have a question that has been bothering me for about 15+ years...

Who is the sadistic screwball who invented covering.
And why is it that some people never have a wrinkle and some do.

I have seen guys with planes that are 300 flights old, and the covering is perfect flawless..

I'll get a brand new plane, and with in 10 minutes it's covering looks like B Arther's face! More wrinkles that one of those dogs with the floppy face.

What gives? I'll tighten it up, and 2 days later it looks like poo.

I'll heat it and message the covering into the balsa with a Hot glove,
2 days later its wrinkled.. Summer , winter, spring, sun clouds, inside outside...
it doesn't matter....

ARRRGGHHHHH...

(This whole post was spurred by the fact that I was taking wrinkles out of my NEW yak that is just sitting in a 68 - 70 deg room. ARRGGHHH... )

[bodywerks]

Covering quality, I imagine.

[jack01]

Violence on TV did it. It's the root of all evil.

Seriously though, covering shrinks at one temp, but to get it to shrink again, you have to get it a little hotter. Eventually, it should quit wrinkling all the time... What kind of covering is it? I had a Hangar 9 Cub that was covered in Ultrakote, and I had to reshrink five or six times before I even got it finished. After that last reshrink though, it never did it again.

[Biff]

Hate to say it, but if you're working with an ARF or have a plane already covered it's usually too late. Sand paper, the LEAST amount of filler possible and heat are the keys to success. Also dark colors are simply going to screw up. Take a temp of light and dark colors on your plane in the sun,,,,it's amazing! Everyone who flies will have one black airplane. Most will have ONLY one. Dark colors absorb heat. Heat sucks!! I never leave a plane uncovered in the sun. After a flight I take it directly under a pop up.

You can over heat covering in a New York minute. Don't think using higher heat will do you any good. Ultra likes temps no higher than around 220-230. Mono can take a bit more. Most ARF's are floated. This means the covering is ironed around the perimeter then using a heat gun, the covering is tightened. If you don't go over the covering with an iron, it will bubble or worse.

The iron should never touch a surface without a sock. I use a sock wire tied to the iron. Around corners you can apply a bit of pressure. On flat balsa surfaces use only the weight of the iron,,never ever push!! Using any pressure at all will ding your work. Hate seeing that!

With Ultra, NEVER get a heat gun near a joint! It will mess up every time. I use a wood yard stick to lay over the joint. Keeping it cool won't allow the seam to pull. Key here is to go slow. REALLY REALLY slow. Allow the heat and weight of the iron to do the work,,not pressure.


If you are covering a new plane don't scrimp on Xacto blades. If you cut everything on glass the blades will last a bit longer. You will also get nice clean cuts. On a new 40% plane I will use over 100 blades. Usually no more than two cuts then change the blade. I keep 5 Xacto knives with different colored tape on the bench. Two "point" cuts then use that blade for a couple of "knife" cuts. Then throw it in the wood cutting pile. The more new blades you use the better the finish will be.



Lay your work out with the least amount of seams possible. I HATE seeing seams! It takes some time to do it this way, but it truly separates the nice airplane from the run of the mill. Fewer seams mean fewer problems. Putting trim over covering is problematic. If you have a solid red wing and want stripes over it you will pull your hair out! Go slow and use low heat if you cant's cut the red and leave 1/4 inch over laps. I try my best to cut all patterns so I don't have to put covering over covering.


Covering is something I truly enjoy. If you are in a rush, don't even break out the iron. It takes time to do correctly. There is no substitute for OJT. You will learn every time you do it. I'm no Dave Jones, but it's just something I love to do. I wish I had more projects to cover! Heck, if I could sand, do prep work and cover airplanes full time I'd be one happy dude! Will post a couple planes I've done.

[JeeUm]

I've gone to using the simple "box cutter" type of blades that can be bought at lowes. I think they actually work better for film and I feel like I have more finesse with them. I'm the same way, I'll go through almost a whole box of 100 on an airplane. Sharp blades are the only way your gonna end up with a clean looking covering job. I actually use higher heat with ultracote, I use the 220 for when I have to put covering down over covering, but will sometimes go as high as 300. Ultracote seems to take a much wider range of heat then monokote will before anything severe starts to happen.

The two points that most important are like Biff said, sharp blades and patience.

[notorious_benny]

Use profilm!! You can heat it all to hell and it just keeps shrinking.

I had a profile covered in profilm that was crashed and bashed and broken many times but the covering always looked good. I am no expert at applying it but with profilm you dont need to be.

[bodywerks]

I'll second that! I did some for-profit building back in my day and got it down. Now, however, I would rather buy one already done...I don't like flying what I build - too much pain if you lose it!

[JPrc]

I got to agree with JeeUmm here. Once you start using the box blades it is almost impossible to go back to using just Xacto blades for covering. I usually buy a new box of 100 blades from Lowe's and use up the whole box on a 40%...Jonas

[SleepyC]

BIFF, JeeUm.. good info...

I never knew the "tacked at the edges" thing about ARF's...
MAN... that changes everything.. I'm going to "properly heat" my entire plane tonight!

See... thats why this site rules... i post a relatively dumb post with 2% of actual content,
and you get back answers that you can't even pay for in books....

THANKS GUYS!!!

[Chris Puckett]

Also when covering an aircraft when you tack down one side pull as hard as you can to put some stretch in the covering. This will not allow the covering to sag. I agree that buy blades by the hundreds and change them out frequently. Around $20 for 100 #11 blades. Might sound expensive but its the same as a roll of covering. Tack down all edges and do not use the iron in the middle unless you are putting down trim. Let your heat gun work for you.

[xtremeRCpilot]

Man I would love to get more into covering as Biff has !!! This is definately an art form. Its always nice to have a pro nearby when your spending this kind of time on a project. I had the maroon Yak 54 AM and it would wrinkle immediatly when left in the sun. I used 320deg to get it smooth again, hope my blue one doesnt do this...Great info, Thanks!!!!

[WOODisGOOD]

[/quote]I wish I had more projects to cover! Heck, if I could sand, do prep work and cover airplanes full time I'd be one happy dude! Will post a couple planes I've done.[/quote]

What are you doing next week? Bring your heat gun and iron.

[DGrant]

It's hard to say why most ARF's look terrible and wrinkley after a few days... I don't want to say it's in the covering, as it supposed to be the same stuff we buy in our LHS, I don't know I believe that though... but the kit-built planes I have don't seem to have that problem. I've got 4 planes that I've built over the last several years, and haven't had to touch them with anything.. no sag whatsoever.... using TopFlight Monokote. I've been covering planes for a looong time, and although it's not my favorite thing... it stays put when done correctly.... I really don't know why ARF's have that tendency to sag though... hmm.... good question.

[JeeUm]

I believe it's a combination of the fact that the planes are built in a humid enviroment and dry out over time as they make their way here, they don't do a great job of getting all the dust off the airframe and they don't pre-stretch the covering enough.

[Flatlandman]

those blades for your Hobby/excacto knifes are soft and lose there edge fast. When i cut a 36" seem it was too dull before i got the whole cut.

I used a 1 dollar utility knifes that has lines scored so you can break a peice off and have mnore use out of the knife. Each on of those lasted way longer than those blades. Give one a try and see what ya think. I use them for every covering job i do

Also i use some double sided razors for doing curves and trimming excess and any thing else that they work for. If you have trouble with the back side cutting you put a layer of masking tape on the back blade.

heres a pick of these tools i use