Construction Tips
Material: The basic building material is 1/8" B flute corrugated
cardboard (CB) with a white paper finish on one side and a brown unfinished paper on the other side. The white paper
finish side, which becomes the outside surface of the model, results in a smooth surface for final finishing.
CB with brown facing paper on both sides can be used, but the finish will not be as smooth and it may take extra coats to
give good coverage with light colored paint. 200 lb test board (a measure of its strength) is the most readily
available material as it is commonly used for CB boxes. 150 lb test board is perfect as it is lighter
in weight than the 200 lb test board, but with adequate strength for model building. But it is harder to find as
this board usually requires a special order.
My main motivation for using CB was to reduce building time and cost,
with the emphasis on cost. Its my hope that you can obtain CB for free. So check local merchants and their
dumpsters to see if you can find some free CB. But a word of caution here! The biggest mistake first time CB model
builders make is to use two plys of 1/8" CB or 1/4" CB which they think is required for added strength. DON'T
DO IT! These designs have been tested and are plenty strong. The added CB is not needed and will only result
in an overweight model with poor flying characteristics.
If you can't find what you want for free, then look to buy some
good quality CB in your area because it is inexpensive if obtained locally. The best way to do this is with
a computer search on "Boxes Corrugated and Fiber". Hopefully, among the results will be a few companies in your
area that manufacture corrugated boxes. A phone call will tell you if they have the 1/8" B flute with the white
paper finish on one side.
However, I still receive email from modelers who say they want to build
a CB plane but can't find acceptable CB building material, either free or from a local box manufacturing source. Several
have asked me about the possibility of having CB shipped to them directly from a local supplier. This is not
feasible as manufacturers would require a minimum order running in the hundreds of sheets. Therefore, I have decided
to stock and sell the same CB material that I use for
all my model building. Go to the "Order Cardboard" page for details.
Glue: Water based glue,
such as Elmers or Titebond, is recommended. Contact cement is not recommended since parts cannot be shifted when gluing
surfaces.
Folding: The scoring of the fold lines is done with a screening tool available at
hardware stores. It consists of a handle with a 1-1/2" radius wheel at one end, which is run along the metal straight
edge on the fold line.
Waterproofing: Waterproofing, if desired, can be applied to the raw CB material
before you cut out the parts. Mix 25% clear polyurathane with 75% paint thinner and brush on the white outside of the
CB sheets and allow 48 hours to dry. I don't waterproof my models as I don't fly in rainy weather.
Finishing: One advantage of CB is that it gives a solid surface with no open areas
to cover (See the completed Moth Minor model below). My finish method is to give 2 coats of clear dope, sanding lightly
between coats with #400 sandpaper, followed by 2 coats of color dope. Coverings, such as Solarfilm or Monokote, can
be used. But with these, it is recommended that the surface not be doped, which will result in a better bond.
Paper Tape: All seams, joints and exposed edges of he model are covered with strips of gummed
paper tape. Cut a thin strip to length, dip in water and smooth it over the seam. Use paper towels to blot
up the excess water on the tape.
Construction Photos
