Shivershot

I started covering my LT-40. First time useing plastic coverings. At the corners I keep getting wrinkles and at the rib areas. I pull it as tight as I can to get the wrinkles out before shrinking but I keep getting them. Trashed a whole role of coating. Need some tips before I waste another one. Please HELP!

danny03

check out this How-To http://www.rcuniverse.com/magazine/a...?article_id=67

pmw

My Feedback: (1)

It sounds like the covering is pulling loose when you shrink it. I have never been able to get any covering to stick to any surface without using an adhesive such as BalsaRite or SigMent. I brush it only on the areas I want to stick, NOT over the entire surface. Just brush it on the edges about 1/2 inch. Make sure the covering is ironed down to the adhesive very well before you shrink it and it should not pull loose.

ho2zoo

My Feedback: (5)

I found the best techniques in a book called "There are No Secrets". Paperback book just about iron-on coverings. One of the best suggestions in it was what I call 'Divide and Conquer'. Say you have a rectangular area, like a wing panel. First tack down corner number 1, then the opposite corner number 3, then corner number 2, then corner number 4. Then tack down in the centers between the corners, doing the opposite sides again; side 1, side 3, side 2, and side 4. Then you tack down in between the previous spots again, going to opposite sides again. When most of the outside edge is stuck down in multiple spots, run the iron around the entire edge to seal it all down. Then work from the edges inward to the center, again alternating opposite sides.

It takes some practice, but it can be done.

Also, be sure to have your iron at the correct temperature. Not hot enough and it won't stick well, too hot and the covering will burn or melt.

SPLIT S

Are you using an iron or a heat gun to do the final shrink? Using a gun to shrink open span areas works much better for me.

Dan

Charlie P.

Cut darts in the excess and pull HARD! It really takes a strong tug to work Monokote around curves and angles. Monokote has a video that's not bad but MinnFlyer's cover the same for free! "Tom's Techniques" and "There Are No Secrets" published by Harry Higley have some good tips, too.

Jester241

Sounds to me that you tacking the corners first(as you should) and then ironing from the rest on moving toward your corners,then you end up having excess covering your trying to get to shrink out near where you first tacked the corners. If so,I had a hard time figuring this out on my first cover job. The only thing that usually shrinks the covering enough for this type of thing is a heat gun. My heat gun is my best friend and I couldnt see how anyone could cover nicely without one(im sure its possible though).

It just takes practice and proper use of a heat gun. I suggest not trying to "iron" out significant wrinkles,but to heat gun them. An iron will simply crease the covering and compact the wrinkles. Get your covering on half decent as your were,then make sure your edges are ironed on,then pretty much heat gun out any wrinkles over the entire surface. And it also took me awhile to realize just how much heat covering could take to shrink out wrinkles. I was always afraid to heat it up enough. You can burn through it though,so be careful. Make sure to leave enough excess covering to trim off around the edges after you get it all tacked down.

If I or we totally understood what you were talking about,please explain again [8D]

And yes Minnflyer video is AWESOME,but he makes it look too easy! And its not.

Mode One

Use an iron, work on the underside of one wing half. Tack down one corner, go to the opposite corner, pull tight and tack. Go to the third corner, pull tight and tack, then go to the opposite pull tight again and tack. Go to the middle pull out wrinkles and tack, Opposite, stretch tack. Middle of the ends, etc... (Is a picture starting to develope here?) Keep dividing in half, until all is tacked down. Then go to the corners again and start working the material around the corners. Work small areas and eventually you will get it smoothly around the corners. Don't iron any wrinkles. Once you have it down where you want, cut away the excess. Flip over and do the top, or the bottom of the other wing half. Once all four panels are ironed down, then take a heat gun and tighten the open areas. Stay away from where the material is ironed down to the framework as you will loosen up all your hard work.

Watch Minnflyers film on the process. Much easier then trying to understand what I've just said!

somegeek

My Feedback: (2)

You can do the work without a heat gun by hovering your iron (on it's highest temp) over the areas you are working to shrink.

I've used ultracote on a few different planes with good results. Minus sanding, no prep of the surface was required with balsarite or the like. The covering has the adhesive you need. Take your time, work from the outside in. Using the shrink to your advantage you shouldn't have to pull hard when tacking the pieces in place. Practice on scrap to heat and pull around corners. Did I mention to take your time? Plan out how you will cover a piece to know where to make cuts an such so you don't paint... er cover yourself into a corner.













Another LT-40 build thread here if interested.

somegeek

Mode One

Pulling tight when applying in the beginning does much towards avoiding sags and wrinkles later on, while the airplane has sat in the sun. So, in my opinion, the covering should be pulled tight enough that few if any wrinkles are left, when applying.

Yes, a heat gun is not necessary and all the heat you need, can be applied with the iron. Embarrassingly enough, I held to this belief way to long until I bought a heat gun and found out how much better/easier this works!