Editor’s note: This great how-to from John Philbrick shows how easy it is to change your aircraft’s appearince with just a few stencils. In this case, he transformed a civilian Cub into a Navy trainer.
My two favorite RC events are Warbirds over Delaware and the Rhinebeck Jamboree. Many interesting models are brought by very skilled builders and pilots, and open flying is offered. So, as long as you are willing to embarrass yourself in front of some of the nation’s top fliers, these are wonderful events to attend.
As my flying skills are at the lower end of the range, I wanted an easy plane to use at both events. My Great Planes Cub ARF has already flown at Rhinebeck, but as a civilian plane, and obviously wouldn’t do at a warbirds event. A phone call to Bob Banka and a little time with his catalog showed a Cub that had been taken over by the Navy for a trainer. It was Cub yellow, but had the insignia and markings that showed it as a military craft.
Meeting the challenges
There were several challenges in making the conversion: removal of the civilian Cub numbers and lightning bolt, selection of paint and acquisition, and application of stencils. Each step sent me up a learning curve, and I hope this article will help some others climb it more easily. The process was assisted greatly by helpful articles and emails from Roy Vaillancourt and by instructions and comments from Gary Siebert, who produced the stencils.
It was tedious but not particularly challenging to remove the Great Planes stickers that constituted the numbers and the lightning bolt. Careful use of a heat gun softened the adhesive so the individual items could be peeled off. Mineral spirits and steel wool removed the remaining glue. There was some residual color change due to the protection the numbers had given the original Coverite. Probably a quick spray of Cub yellow might have improved things, but I felt that time and more sun would take care of that difference.
Color choice was the next challenge. Based on Roy Vaillancourt’s experience, I used latex paint. Getting black for the alpha numerics and white for the stars was easy. The blue should be insignia blue, to be matched to Frank Tiano’s color book. The red was a challenge. I blew up a closeup of the rear of the fuselage, and asked my local hardware store to match that color, and, while they were at it, to match the insignia blue. They came through with perfect matches.
Gary Siebert worked from a copy of the picture plus the measurements I took from my model, and provided me with the required stencils in short order. He also provided a good set of instructions on how to handle the stencils themselves, but I discovered that positioning them was an interesting challenge.
Measuring and placing
Let’s consider the simpler set of stencils first‑a set of numbers. My first step was to draw lines that extend to the top and bottom and the left and right edges of the letters themselves and to the top, bottom and both sides of the stencil. Then, I used a centering ruler to find the centers of each edge and the center of the whole set of numbers. Careful measurements on the original plane’s photos told me that the letters on the tail were centered two letter heights down from the top of the fin, and were centered from left to right on the fin. The centering ruler came in very handy to position the stencil.
The stars were a little more challenging. Gary has done an excellent job of setting them up so that the star will be centered on the circle. He does this by having the modeler tape a thumbtack in the desired center of the insignia. The circle is then impaled on this thumbtack via a tiny hole that Gary has placed on the backing for precisely this purpose. The tack remains in place while the fir
st color is painted, then the second (star) stencil is impaled on the same tack, and the second color is painted. This does a beautiful job of registering the two elements. There are a couple of challenges, though, including where the insignia is to be placed and how the star should be oriented.
Again, examination of the original plane’s photos showed that the insignia was just in front of the aileron hinge. The outside edge of the circle was tangent to the extension of the aileron edge. The centering ruler came in handy again.
Gary supplies his stencils in three layers: a backing, which protects the adhesive on the stencil itself, the stencil and a top layer that holds the parts of the stencil together until it is adhered to the plane. He recommends that the whole stencil be carefully held in position with a piece of tape after it has been impaled on the pin, and the backing be cut away carefully to allow the stencil itself to stick down to the plane. I found that it worked best to cut the backing over center and leave a small piece of the backing that can be easily removed once the top layer of the stencil is lifted off.
But the interesting part is the orientation of the star. Clearly the stars need to be lined up so that they appear to be square with the airplane. I drew lines, extending the top of the arms of the stars to the edge of the stencil, and then carefully measured to ensure that each arm was the same distance from the aileron hinge.
Spraying was done using the techniques Roy Valliancourt has documented in the past. In an email, he suggested that the stencils should get a couple of light coats at the edges, dried with a heat gun, before gently building up the color in several additional lightly sprayed coats. I found removing the stencils a challenge, particularly with the small size of the alpha numerics. Gary helped by suggesting that I use the heat gun to soften the stencil’s adhesive. In some cases, I found it useful to carefully cut along the edges of the letters and numbers, and then, while removing the stencil, to help it separate from the paint with the sharp edge of an X-Acto knife. In a couple of spots, I needed to touch up the numbers and letters with a brush, or scrape away small pieces of unwanted black. The stars and circles, being of larger scale, caused much less of a problem. The only trick that I wish I’d used was to not paint the thumbtack and its supporting tape when doing the initial blue. Gary suggested that I should have feathered the blue as it approached the thumbtack, so that there wouldn’t be sharp lines to clean up when the white went on. But a little brush work and a little steel wool minimized the problem in my case.
All of this wound up with results that pleased me, particularly for a first-time user of these techniques. You can see that the insignia looks quite good on the wing, and the plane came out quite well, too. Now, if I can just keep it going straight on the takeoff, and get it to land somewhere near the runway…
Many thanks to Roy Vaillancourt for his helpful articles and email, to Gary Siebert for his skillful stencils and helpful comments and to my son, Whitney, for convincing me to stretch my skills this way.
Here’s the author showing his Cub as originally built.
The circle and star insignia is centered between the wing leading edge and the aileron gap by taping down the registration tack in that location.
The arms of the stars are oriented parallel to the aileron gap by equalizing the distance between the point and the gap on each side.
The stencil backing is cut away so that a remaining piece is easily removed once the stencil itself is revealed.
This shows the results of cutting away the stencil backing.
Here’s the wing after the stars have been sprayed on and the stencils removed.
This is a side view of the completed NE-1.
The stencil with the numbers is positioned horizontally by measuring distances between the fin leading edge and the numbers themselves, with the assistance of lines drawn on the stencil at extending the edges of the leading and trailing figures.
This is the prototype being modeled, as obtained from Bob Banka’s Aircraft Documentation.
The stencil is positioned vertically by measuring against lines drawn on the stencil in comparison with the top of the fixed fin.