bluestratos

I have covered planes for years and have no problem doing a nice job.. but without fail, slack and wrinkles form after the plane has sat for a while. What I think I need to do is to stretch the covering more and rely on shrinking less.. now this is easy for small parts but what about a wing? Suggestions on how to pre load with stretch so wrinkles are less likely to form later?

Regards,
Randy

rkrider

I think you may have figured out your'e problem. The instructions that come with monokote describe covering open bay wings pretty well. Spend some time and get the covering as tight as you can buy pulling and sealing the perimeter with LOW heat. Don't seal ribs so the monokote can shrink evenly. Do both sides and then use your'e heat gun to evenly shrink (keep it moving) the surface. Crank up the heat on your'e iron and seal ribs and go over edges again. The tighter you can get the covering before hitting it with the gun, the better it will hold

MinnFlyer

My Feedback: (4)

It seems to me that no matter what you do, time and temperature changes will alway show up as wrinkles.

I just plan on periodically breaking out the heat gun and giving trouble spots a quick touch-up.

ecmiller

The expansion and contraction of the air sealed up inside the wing rib bays is what causes the covering to stretch and wrinkle. Once the covering operation is completed, take a straight pin and poke a single hole in each rib bay under the wing next to the structure so the air can escape as it expands. Works great for me.

piper_chuck

My Feedback: (12)

I always put holes in each rib before covering so the air can work it's way to the servo cutout(s).

piper_chuck

My Feedback: (12)

Tack one inside corner, perhaps the center near the leading edge. Pull the covering tight toward the next corner, and tack this down. Do the same with the other two corners. At this point, the covering should be snug, and there should be no wrinkles. If there are, pull up the appropriate corner and retack it. Once you're happy, tack down the edges between the corners. Note, do not slide the iron back and forth while tacking beween corners. Place the iron in one spot, lift it, and place in another spot. It also helps to keep dividing the untacked sections in half so you don't end up with a buldge. When you've completely tacked down one panel (you start with the bottom of the wing), do the opposite (top of the wing) before you begin shrinking. When you do start shrinking the covering, do some on the bottom, some on the top, and keep going back and forth till both are tight. If you try to shrink one side before the other is done, you risk a warp.

Stick Jammer

Not really. It's usually lack of humidity that causes most of the wrinkles to appear after the plane has been sitting for awhile, typically over the winter. That's the biggest reason most ARF's have a lot of wrinkles. They're built in highly humid environments and then shipped to where the humidity is much less. The wood shrinks because of the lower humidity and the covering is no longer tight. If a few slight wrinkles appear from winter storage, wait until the summer humidity returns before trying to shrink the covering more. A lot of them will fix themselves.

bluestratos

I have always stretched the covering as I tack but I think some how there must be a way to do more... stretch under heat would pretension the covering but its hard to get enought heat on a wing to even stretch. This was what I was wondering about... just imagine if you could heat the film in an oven and pull over the parts...shame that after all these years this remains a problem.