visitor Kenneth E. wrote to say that he is working to build a complete collection
of the Tenderfoot models that were published in American Aircraft modeler.
The Tenderfoot series was an attempt to provide motivation to young newcomers
to the hobby. They were a mix of freeflight rubber, gliders, and 1/4A &
1/2A control line designs that built simply and cheaply.
requested reprints of the following three models:
Saucerer, Ray Malmström:
C/L 1/2A, January 1970
Bonanza and Mustang,
David Thornburg: FF HLG, January 1971
Denson: FF Rubber February 1973
A simple-to-build and fly model that IS different.
By Ray Malstrom
FLYING fun comes in all shapes and sizes, and it certainly will be yours,
if you circulate with this circular-shaped space-age flavored flying saucer.
Saucerer is lively sport ship for learning to fly upside down, loops,
and wingovers. Being almost unbreakable, it is a fine confidence builder.
It uses 049 engine.
Full-size plans on next two pages include many helpful building sketches.
Plane is mostly 1/4" sheet balsa. No airfoil, as such, is carved, but
bevel wing edges.
Before painting, sand model all over with fine sandpaper. Blow off dust
and brush on several coats clear dope. Use extra fine sandpaper between
coats, then trim with color.
Construction: Cement together 1/4" balsa sheet
cut to the dimensions in Fig. 1. Draw a center line across the sheets, and
with a pair of compasses draw an 11" diameter circle. From the plan, trace
and transfer to the circle the angled cutout for the motor mount, the elevator
line and the small square that will accommodate the bell crank mount D.
Using a fretsaw, cut out the disc (Fig. 2). Bevel the edges with fine sandpaper.
Cut the elevator apart and rejoin using nylon or silk hinges. Cut a small
slot in the elevator where shown for the control horn. Cut the body from
1/4" sheet. Note that it is tapered (use sandpaper on a block for this)
towards the rear. The rear of the fin is cut away and re-cemented back at
an angle (Fig. 3).
Now cement body piece along top centerline of
disc. Cut hose blocks A, Band C from block balsa. Shape with knife and sandpaper
and cement in position. Gouge out recesses for bolt heads (Fig. 4). Cut
engine mount from 1/4" plywood, and drill holes to suit the engine you intend
to use. Insert mounting bolts from the back, and solder pieces of wire across
the heads to prevent them from turning (Fig. 5). Firmly cement the engine
mount into the cutout on the disc and against the face of blocks A, Band
C. Make a really firm job of this, and see the engine mount points the correct
amount to the right.
Cut a bellcrank from 1/16" ply (or use a metal
or plastic commercial bellcrank of similar size), and bellcrank mount D
from 1/4" ply. Drill D to accept to bolt, and make sure it is a tight fit.
This is important. Cut control rod, and leadout wires over-length at this
stage and assemble to bellcrank, bending as shown (Fig. 6). Pass the bolt
through the central hole in the bell crank, slip on a washer or two (Fig.
7), and screw firmly into part D. The bellcrank mount (complete with bellcrank
and wires) is firmly cemented into the square recess already cut in the
disc (Fig. 8). Make the line guide, drill holes, and slip it onto the leadout
wires and cement to the undersurface of the disc in the position shown.
Do not yet form the hooks on the leadout wires.
Cement the 1/16
ply horn into the elevator slot firmly. Use plenty of cement. Connect rod
by bending the end and slipping through the hole in the control horn and
locking with a soldered washer (Fig. 9). Be sure the bellcrank is in the
position shown on the plan and the elevator is neutral (flat) when you connect
up. Now cut off the excess from the leadout wires and bend the hooks. The
hooks should be level (as shown on the plan) when the elevator is in the
neutral (flat) position. Take care over this connecting up, as accurately
lined-up controls make for really sweet and easy flying. Add a small weight
to the starboard edge of the disc as shown. Hold in place with several layers
of tissue doped on. Finally dope and finish your Saucerer as detailed on
the plan, and bolt the engine in position.
Before that eagerly anticipated first flight, balance your flying saucer
carefully. Tie a length of thread to a pin, and push the pin into the body
at the balance point shown on the plan. Your model must balance level. Slight
nose-heaviness does not matter, but tail heaviness must be avoided. It is
unlikely that you will need any weight at the rear, but with varying engine
weights you will most likely need a little additional weight in the nose.
This can be achieved in two ways: Simply by adding some sheet lead (only
a little will be needed) under the engine mount and block C, or by cutting
a false firewall from plywood (around 1/4" to 1/2" thick) and positioning
it between the engine and its mount. This way you move the engine further
forward and achieve correct balance without the necessity of adding extra
weight. Fig. 8 explains this simple and very neat method of balancing. Take
your choice, but either way, do make sure your Saucerer balances on the
balance point. You'll be glad when you take off on that test-flight!
Wing-overs and loops are possible with Saucerer after you are acquainted,
so good luck and happy circulating. And choose soft grass to fly over.
Three 1/4 x 3 x 36 balsa,
one 1/4 x 3 x 20, one 1 x 6 x 1, one 2 x 2-1/4 X 3/4, one 1/4 x 2 x 2 plywood,
one 1/16 x 2-1/2 x 1-1/2, one 1/32 x 2-1/2 x 1/2, one 9" length 1/16 music
wire, one 14" length 1/32 music wire.
<click for larger version>
The AMA Plans Service offers a full-size
version of many of the plans show here at a very reasonable cost. They will scale the plans any size for you. It is always
best to buy printed plans because my scanner versions often have distortions that can cause parts to fit poorly. Purchasing
plans also help to support the operation of the Academy of Model
Aeronautics - the #1 advocate for model aviation throughout the world. If the AMA no longer has this plan on file, I
will be glad to send you my higher resolution version.
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June 26, 2011