“Motor.” Refer to Figure 5. It was not a wimpy plastic DC
motor powered by two AA cells, but an all-metal, multispeed, reversible, 110 VAC power mover. Just add a pulley
and you had a winch that could do some real work.
The motor that came with the set I bought had some
chipped paint, was a little grimy, and needed a new power
cord, so I took the opportunity to completely refurbish it
to its former glory. Listening to the sound of its newly
oiled gears going round and round was music to my ears.
Plus, it was reversible with the movement of a small
handle that engaged a sequence of gears. I remembered
back to when I first learned how to set up gear ratios in
order to slowly raise a lift bridge or rotate a Ferris wheel.
As some of you might recall, the 8-32 nuts that came
with the sets were square instead of hexagonal and
sometimes were painful to hold and tighten on the bolts.
The square edges would jab into your fingertips (Figure 6).
Therefore, my first step was to set aside the original nuts
and buy several gross of modern small pattern hex nuts.
No more sore fingers!
It took me a couple of days to build the basic Ferris
wheel structure and get it spinning freely on the axle. The
manual showed a pulley mounted on the motor and
another larger one on the wheel axle, connected together
by a long loop of string that was supposed to act as a belt.
No joy! The string slipped on the pulleys no matter how
much tension was applied. Then, I recalled a toothed belt
and pulley arrangement that I had used during my
FIGURE 7. The manual showed a drive belt made of string but
it slipped, so I substituted a cogged belt. Sweet!
FIGURE 5. The Erector all-metal 110 VAC type A49 motor has
extra holes for various gear ratios and reversible operation.
FIGURE 6. The set’s 8-32 square nuts fit nicely into tiny
spaces, but are painful to tighten with your fingers compared
to hex nuts.
▼▼▼▼ ▼ ▼▼ ▼ ▼▼▼▼ ▼▼ ▼
A handy reference book is
Greenberg’s Guide to Gilbert
Erector Sets shown in Figure A. It
has full color pictures of every set
and even has a listing of each and
every part in all the different sets.
For example, in 1950, a No. 10 1/2
set contained ( 52) 10” girders, ( 26)
5” curved girders, ( 4) 7” axles, ( 4)
3” disc wheels, (271) 8-32 square
nuts, and hundreds of other parts.
If you’re interested, Wikipedia has
a brief history of Erector Sets on
DESIG COMPONENT SUPPLIER
BELT Cog Drive Belt, 33" PIC Design, FA-336
BOX1 Chassis, 3x4x5, Aluminum Digi-Key, L104
BRD1 MP3 Player Shield SparkFun, DEV-12660
C1 Capacitor, 100 mfd 25V Digi-Key, P10269
CHAR1-9 Characters, Cartoon Toys-R-Us
D1 Diode, 1N4001 Digi-Key,
PS1 Power Supply, 12V 1A RadioShack, Vintage
PULLEY1, 2 No-Slip Pulley, 40 teeth PIC Design, MGP2-40
Q1 NPN transistor, 2N3904 Digi-Key, 2N3904FS
R1 Resistor, 10K Dig-Key, 10KQBK
RLY1 Relay, 12V, DPDT RadioShack, 2750043
S1 Rotary Switch, Four-position Junk Box
S2 Toggle Switch, SPDT Digi-Key, CKN1023
S3, 4 Microswitch, Roller, SPDT RadioShack, 2750017
S5 Pushbutton, N.O. RadioShack, 2751556
SET1 Erector Set, #8 1/2, c1950 eBay
SPKR Powered Speaker/Amp RadioShack, Vintage
SR1 Slip Ring, Six-conductor eBay, China
U1 Arduino Micro w/Headers Adafruit
April 2017 37