First of all, I know very little about plastic coverings, although I bought an iron and sock and a heat gun in anticipation of future needs.

A while back, I bought a Brodak P40 ARF and have had it up a couple of times.  Last time out, I ran out of fuel in the clover and ended up slack lines into the ground , hitting on the outer wingtip.  It was obvious that internal damage occurred because the covering was wrinkled.  I went home and opened it up.  There was a broken rib and a cracked wingtip.  I had previously obtained a few feet of Brodak covering in gray, camo green and black in anticipation of repairs.

I got the tip rebuilt and made my first attempt at plastic covering.  I cut a piece of the gray to fit, but it wouldn't stick.  All it did was shrink.  At this point, I thought I got bad covering or I was missing something.  I looked at the roll of camo green and the roll of black and discovered a transparent backing that could easily be separated from the face sheet.  Both the camo green and the black had one edge that showed the transparent backing.  However, the gray roll didn't have that edge leader that made it possible to pull apart.

So, my question is how to separate the backing from the color side when there isn't anything to grip?  I spent quite a while trying to find a way to remove the backing and finally achieved results with the help of an Exacto knife.   There must be a better way!  At any rate, I recovered the repaired wingtip with success.  At this point, I have a better understanding of the process of covering, but still need to know how to separate the backing sheet.

Dick, try putting two pieces of scotch tape, one on each side and rubbing it in and then pull the pieces apart.

Well, once I got the covering free of the carrier sheet, I repaired the wingtip with satisfactory results.  The patches were about 4X6 and extended from the last wing rib to the tip.  The broken rib was the tip rib.  I used the iron to seal the edges and then shrunk the center areas.  I was satisfied with the results, since I had never used plastic covering before.  After it was all sealed and shrunk taut, I painted on a layer of epoxy around all the edges, to prevent exhaust leakage and to be sure it wouldn't come loose.  I am intrigued enough to try to cover a plane.  I have a Walter Umland Coyote almost finished and am toying with the idea of orange Ultracote with black trim.  I scratch built the Coyote in 1968 when it first was published and painted it orange and black.  I think I need to get this out of my system to decide if I like it or want to go back to silkspan and dope, which I haven't done since 1975.

Dick, I hope that tape method worked for ya. John that plane looks awesome. I really like designs that are not the norm.