Originally Posted by
jester_s1
I've covered a few planes and can get a nice tight look that will last. My only problem is when cutting the seams around a wingtip or other curved surface, I always get this jagged line. I shrink the covering around the tip, which of course causes it to be wavy on the other side, and I just haven't figured out how to cut it so I get a smooth line to iron down on the bottom. What do you guys do?
Suspect the problem you describe stems from cutting away the excess material during the covering process after it has been stretched and pulled for areas that have compound curves and relying on the natural contour as a guide for the cutting tool. This technique results in a wavy or jagged line especially visible with contrasting colors.
Plan for your overlap. The material needs to be pulled and stretched past the point where it will be trimmed for both the underlying section and the overlapping section. Once the material is down against the structure where you want it, you can mark it. In both cases (underlying/overlapping), I use a Sharpie pen and a flexible, plastic straight-edge (a piece of 1/16" balsa sheeting works here too) to mark the line to follow for the cut which will be as straight as you make it. After cutting, seal down the edge (to prevent ink bleeding), then use alcohol or acetone to remove the Sharpie line. For dark colors where a Sharpie pen line won't be visible, use one edge of masking tape to demark the line to follow. Remember to pull the tape back on itself so you don't lift or tear the covering.
Always use a virgin, single edge razor blade for trimming excess covering from the wingtips, place the razor on the Sharpie line and pull the covering against the blade so it doesn't cut into the underlying structure/covering. IOW, place razor blade, pull to shear, move razor blade, pull to shear, move razor, pull to shear... Oh, and make sure the blade is always in contact with the supported covering surface. Its tedious going one inch or less at a time but results in a very straight line.
Passing on a technique learned from expert modelers; hope this helps.