Darcy | Rubber Band Airplane!

Here is a cool alternate version of the Squirrel. It uses copy paper instead of tissue paper. It was prepared by Brett Herrick from the First Flights program.

The Copy Paper Squirrel is a low cost, rubber powered airplane that flies well and is easier to build than the Delta Dart. The Copy Paper Squirrel is easier to build than the Delta Dart because all of the balsa sticks are cut at a ninety degree angle and can be pre-cut to specified lengths so that no fitting of the balsa sticks is required. The Copy Paper Squirrel also has the advantage that the position of the wing on the fuselage can be adjusted (i.e. the wing is held to fuselage with a rubber band) making it easier to adjust it to fly well. I use the Copy Paper Squirrel project as the project that follows mastering making the balsa glider projects but to be built prior to making the Delta Dart project.

The Copy Paper Squirrel was developed for use with the First Flights classes. The biggest difference between the Copy Paper Squirrel and the Squirrel is that it is built on plans rather than on top of tissue paper (i.e. this makes it easier for younger kids to build it). The Squirrel was designed by Darcy Whyte and he has graciously given his permission to use the material that he has developed for the Squirrel. His website describing the Squirrel is http://www.rubber-power.com/

Copy Paper Squirrel Bill Of Materials

Copy Paper Squirrel plans

To build the Copy Paper Squirrel one needs to purchase the materials listed on the Bill of Materials and print out the plans (i.e. the plans need to printed full size on 11” x 17” paper. If the plans are printed out other than full size the precut balsa strips will not fit properly). For the materials that may be difficult to purchase locally, I have listed the sources that I have used below:

The balsa can be purchased from a local hobby store or ordered from Balsa USA (i.e. WWW.BALSAUSA.COM ). You can either make the balsa strips by cutting them from a balsa sheet or buying them precut. A razor saw and mitre box work well for cutting the strips to the desired lengths.

Balsa Strip Description Quantity Needed
——————————- ———————-

1/8” x 3/8” x 12” 1

1/8” x 1/8” x 4” 1

1/16” x 3/16” x 2” 7

1/16” x 3/16” x 6” 1

1/16” x 3/16” x 12” 2

1/16” x 1/8” x 12” 1

If the # 8 rubber bands can not be purchased locally, they can be ordered from Keener Rubber by contacting them at sales@keenerrubber.com . Their AMP crepe rubber bands can be purchased in several different colors.
The propellers used for this project can be purchased from the AC Supply Company (i.e. www.acsupplyco.com, # MID382, 5 1/2” replacement propeller assemblies, 35 pieces).
The 3/32 inch wide rubber used for this project can be purchased from AC Supply Company (i.e. www.acsupplyco.com, # AC1701, 3/32” Tan Super Sport Rubber, ½ pound). A 21 inch long strip will be needed for each model. For flying outside you may prefer to use 1/8 inch wide rubber strip.

Regarding materials that can be purchased locally:

The piece for holding the rubber band to the rear of the Motor Stick can be made by cutting a toothpick in half. Toothpicks that have a square center section work particularly well for this.

To build the Squirrel I recommend the following supplies and tools:

Razor saw and mitre box simplifies cutting the balsa sticks at a ninety degree angle. Further, setting up a “stop” simplifies cutting many pieces to the same length.
14 ¾ x 11 ¾ inches Hardboard sheet (i.e. similar to peg board but without the holes) to have a flat surface make the model on. Six pieces can be made by ¼ inch thick 2 x 4 foot sheet. This is the same as used by the Delta Dart project.
Masking tape – to hold the wing pattern to “build board” described above
Gel pen – these pens are better for marking on balsa
Glue stick – washable “lipstick tube” type
White glue, Aleene’s Quick Dry Tacky Glue is preferred because it dries quickly
Wax paper or similar – for putting a puddle of glue on it
Toothpick – for applying the glue from the puddle of glue
Sanding block with fine sandpaper
Flexible ruler
Scissors
Modeling knife – with the younger kids it is recommended to use a scissors instead of a modeling knife for cutting out the patterns
Magic Markers, optional for decorating the model. Permanent markers bleed less on the balsa and paper than washable markers.

Building the Fuselage

On the Motor Stick, locate the wing position marks and mark them on the Motor Stick with a gel pen.

Glue the Wing Seat to the Motor Stick by applying the stick glue to both pieces and then positioning the Wing Seat between the wing position marks on the Motor Stick. In positioning the Wing Seat on the Motor Stick, the Wing Seat needs to be flush with the top of the Motor Stick. Placing the Motor Stick upside down on a table top can assist in helping to get the Wing Support flush with the top of the Motor Stick. Once the Wing Support has been located, lightly press on the Wing Support to get it to adhere to the Motor Stick.
Cut the paper Vertical Fin and Horizontal Stabilizer patterns from the plans. In cutting out these patterns try to keep them as flat as possible (i.e. no wrinkles).
To make the Vertical Fin, apply the glue stick glue to one side of a of 1/16 “ x 3/16” x 2” piece of balsa, locate the piece of balsa on Vertical Fin and press down on the balsa to get it to adhere to the paper. Note: as shown on the plans, the balsa is to extend beyond the bottom edge of the Vertical Fin.
To make the Horizontal Stabilizer, apply the glue stick glue to one side of a of 1/16 “ x 3/16” x 6” piece of balsa, locate the piece of balsa on Horizontal Stabilizer and press down on the balsa to get it to adhere to the paper.
Cut a toothpick in half and then round off the sharp end using sandpaper.

Copy Paper Squirrel – Fuselage parts

The Vertical Fin is to be located to the Motor Stick as shown on the plans. Namely, the back of the Vertical Fin is to be flush with back edge of the Motor Stick and the bottom of the Vertical Fin is to be flush or above the bottom of the Motor Stick. To attach the Vertical Fin to the Motor Stick, glue stick glue is to applied to rear 1 – 2” of the Motor Stick, tacky glue is to be applied with a toothpick to the front of the Vertical Fin (i.e. balsa stick) where it will touch the Motor Stick and then press in place.

The modified toothpick is to be glue to the front of the Vertical Fin with tacky glue. The rounded end of the modified toothpick is to point downward and the top of it is to be flush with the top of the Motor Stick. This modified toothpick is to be coated with tacky glue where it will be in contact with the Vertical Fin or Motor Stick and then press in place.
The Horizontal Stabilizer is to be located to the Motor Stick as shown on the plans (i.e. the balsa stick is to be underneath the paper). Namely, the front of the Horizontal Stabilizer is to be against the back edge of the Vertical Fin and the top of the Horizontal Stabilizer is to be flush with the bottom of the Motor Stick. To attach the Horizontal Stabilizer to the Motor Stick, glue stick glue is to applied to rear 1 – 2” of the Motor Stick and tacky glue is to be applied with a toothpick to the front of the Horizontal Stabilizer (i.e. balsa stick) where it will touch the Motor Stick and Vertical Stabilizer. Then press in place with the dashed lines aligned to the Motor Stick.

Copy Paper Squirrel – Fuselage completed

Copy Paper Squirrel – Fuselage upside down 2

Set the fuselage off to the side and let it dry. One way to do this is to allow the tail to hang over the edge of table.

Building the Wing

Cut the paper Wing pattern from the plans by cutting on the dark line at its perimeter.

Transfer the 3 wing centerline markings to the other side of the Wing pattern.
Fold the wing tips on the bend line onto the top of the wing bottom and then crease it at the bend line. Fold the wing top on the bend line onto the top of the wing bottom and then crease it at the bend line. Be careful that these creases are on the bend lines and are straight. Lining up a ruler on these fold lines will make it easier to accurately located these folds. Then, bend these back so that they stick straight up.

Copy Paper Squirrel – Folded wing pattern

Attach the Wing pattern to the building board with a strip of masking tape at the rear portion of the Wing pattern. The masking tape is not to cover the wing pattern where the balsa sticks will be glued to it.
The 1/16” x 3/16” balsa strips are to be glued to the Wing as shown on the Wing pattern. The glue stick glue is to be applied to the balsa wherever it touches the paper. When gluing the balsa sticks to the vertical paper surfaces using a ruler or similar to support the paper can be of assistance. Where balsa touches balsa, tacky white glue is to be applied to one of the surfaces with a toothpick. The balsa sticks are to be glued to Wing Pattern in the following order:

1.) The 1/16” x 3/16” x 12” balsa stick on the leading edge

2.) The three 1/16” x 3/16” x 2” balsa sticks in the middle of the wing

3.) The 1/16” x 3/16” x 12” balsa stick on the trailing edge of the wing

4.) The two 1/16” x 3/16” x 2” balsa sticks in the wing tips

5.) The 1/16” x 1/8” x 12” balsa stick that forms the top of the wing

Copy Paper Squirrel – Wing with balsa sticks

To cover the top of the wing, crease the top of the Wing over the leading edge of the wing, apply stick glue to the top of the trailing edge of the wing and then pull the wing top over the top of the wing. The paper is to be pulled tight with the edge of the paper parallel with the rear edge of the trailing edge balsa stick (i.e. the more even the wing top covering lines up with the trailing edge of the wing the less twist the wing will have and the better this model will fly). Then press down on the paper to make it adhere to the balsa stick.

Remove the wing from the building board and trim the excess paper on the trailing edge of the wing.
The a 2” long piece of 1/16” x 3/16” balsa is to be glued to the center of the bottom of the leading edge of the wing with a glue stick. Forgetting to install this Wing Shim will cause the completed model to dive down rather than fly level or climb.

Assembly of the Copy Paper Squirrel

Assemble the wing on to the Motor Stick. Slip a # 10 rubber band over the nose of the Motor Stick. Place the wing with the leading edge facing forward on the top of the Motor Stick near the front of the Motor Stick. Pull the rubber band over the top of the wing and around the nose of the Motor Stick. Position the wing so that wing is in the middle of the marks on the top of Motor Stick and the marks of the top of the wing are centered on Motor Stick.

Push the propeller assembly onto the front of the Motor Stick. It may be necessary to slightly compress the front corners of the Motor Stick to allow the propeller assembly to be installed. Also, the eyelet is to hang beneath the Motor Stick.
To form a rubber band motor tie a knot on the ends of the 21 inch long rubber strip. Install the knotted end on the half of toothpick and the other end on the eyelet of the propeller assembly. 3/32 inch rubber strip is recommended for indoor flying and 1/8 inch rubber strip for outdoor flying.

Copy Paper Squirrel – Finished project with tan background

Flying of the Copy Paper Squirrel

1) Adjust the position of the wing on the Motor Stick so that when on puts a finger under the middle of each wing tip that it balances.

2) Hand wind the propeller 50 turns for the first flight.

3) To launch the Copy Paper Squirrel hold the model between your thumb and index finger at the middle of the Motor Stick. Let the propeller go and gently toss the model horizontally.

4) If it dives to the ground, then move the wing forward. If it goes high and stalls, slide the wing back. The reference marks on the top of the Motor Stick are so that one can tell how far forward or rearward the wing is.

5) To keep it from turning, slide the wing out horizontally in the direction that it turns. The reference mark on the middle of the wing is so that one can tell how far the wing is shifted.

6) When it lands, the wing may move. If so, it will be necessary to reposition the wings relative to the reference marks again.

7) As the Copy Paper Squirrel gets adjusted, increase the number of winds on the propeller by 50.

8) It is better to let the model land itself than try to catch it out of the air (i.e. you are likely to damage it if you try to catch it).