wizardsrun

"Wizard's Run" is my latest rolling ball sculpture. It is 77
inches tall, and uses 5/8" steel balls. The balls are constantly
being lifted to the top, where they wind their way down
twisting, spiralling tracks, occasionally leaping into the air
off of the tracks and performing some tricks on the way
down. Switches at the top direct the balls to 5 different
paths going down, but in two places the balls go back up,
and then continue down on other tracks. The magic carpet
carries one ball up, and the wobble lift brings up two more.

The tracks are made of stainless steel wire 0.102" diameter,
and TIG welded. There are insects and spiders made of
brass and copper, and mechanical devices made of brass.
Four microcontrollers (computer chips) orchestrate the
movement of all of the electrical components.

There is a small stage where a ball rolls in from the back, and the stage lights
up with color changing lights. The track drops down, leaving the ball
suspended under a magnetic field. It then flies out to the right and goes onto
another track. There, it lands on a train car to get carried away to dump the ball
off elsewhere.

The train car is powered by a Stanton Drive, which is a small HO train motor
that has electrical pickup and power on all 4 wheels. One wheel has a
connecting shaft mounted off center to move the pumping arm and the little
bugs that pump it.

The wobble lift brings two balls up, by picking each one up with a claw. The
claw is on a small arm that pivots up and drops the ball into the next claw. Three
claws bring the two balls up to another track. The way this works is hard to
describe, but in the video a picture is worth a thousand words.

click to enlarge

A magic carpet carries the ball up at one point, to put the ball into a series of
4 chutes that launch the ball through the air to the next chute. It is controlled
by a stepper motor, cranking a trolley up a track using fishing line and
counterweights. There are ball bearings almost everywhere, for minimum
friction, and maximum smoothness of the motion.

As the carpet goes up, it rocks back and forth, and when it gets to the top it
rocks forward even farther to tip the ball onto another track. The stepper
motor that drives the movement trolley also causes the rocking, through a
series of gears driving a pulley that changes the distance of pull on the
rocking control line. Without the gears, it rocks back and forth too fast, with
the gears it has a slower movement similar to a "real" magic carpet. Magic
carpets are real, aren't they? ;-)

One track at the top waits until there are 4 balls, and then sends all four down a track, into the air, to
bounce off a pad, back into the air to then land in a funnel. My other rolling ball sculptures have had
a bounce in them, which is very popular with the viewing public, and I enjoy this part too. The
bounce pad is made from a slice of a Superball®.

Two tracks each wait for two balls, so that the balls can chase each other on the way down. There is
a tunnel of 95 red LEDs, that follow one pair of balls with a tail of lights as they go through the
tunnel.

TheWobble Lift

View of lower right.

Comments?
Questions?

The Wizard on his
levitation stage.

The train, with its trailer
holding a ball.

Each "claw" is like a very small section of track, very curved, and a with a very tiny third rail of track
for the exit direction. The claws are on a shaft driven by a bearing set at an angle to the shaft.
Opposite the claw on a shaft is a tiny ball bearing riding in a guide made of pieces of brass. As the
shaft moves, the guidance keeps the claw moving in the right plane to transfer the balls. The guides
are adjustable in their slanted alignment, to adjust the exact position of each claw for receiving and
dumping the ball that it carries.

To make the wobble bearings, I soldered a piece of 1/4" tube to a brass ball. Then I turned the
outside of the ball into a flat ring that matches the inside of the bearing. Remove the tube, and
resolder it to the ball at an angle to the plane of the bearing ring, and then bore a hole through the ball
for the drive shaft. Then remove the tube from the ball. The ring surrounding the bearing is brazed to
the wobble shafts, and is made of a piece of steel pipe. I couldn't find pipe the exact diameter that I
needed, so I brazed some blobs of brass into the inside of the rings, and then turned the blobs to the
correct inside diameter to fit around the outside of the bearing.

This was a major challenge to get it to work, but in my opinion it was worth it.

Would I ever make a RBS with this as the primary lift mechanism? No. Too much trouble for a long
lift. Three wobble arms was enough of a challenge, and it makes a nice highlight among other rolling
ball tricks.

The Sling

The Magic Carpet's
movement trolley

In the center of it all is a glowing ball of light. The light is constantly swirling
colors, and the colors are constantly changing through all colors of the rainbow.
Inside are 3 Luxeon high-intensity LEDs: red, green and blue. Each LED is getting
brighter and then dimmer, and each one does this at a different rate, so that the
colors are always different. The pattern repeats itself once every 214 years. :-)
The LEDs change intensity by blinking about 100 times a second, and the length
of the blinks determines the apparent brightness of the light. The camera can't
capture this effect adequately, and the Detail Video at the end does a mediocre
job of catching the effect.

Here a spider hangs onto a ball which is floating underneath a wood ball, and
held in place by a spider web (fishing line called "Spider Wire") below it. The
ball is actually a very strong neodymium ball magnet, and embedded inside of
the wood ball is another cylindrical neodymium magnet. There is about an inch
between the two, and the spider is always in a wiggling motion due to the
vibration of the whole sculpture.

Wizard's Run will be on display at the California State Fair in Sacramento, July 14 to August 1, 2010,
in the Fine Art Building (in the Expo Center, building 7 at the bottom of the ring of buildings).

The Magic Carpet

The sling catches a ball in a claw, causing the claw to spin around two+ turns,
then spin back and put the ball onto another track. This requires a long run of
steep, straight track to give the ball some good force to get it all spinning.

A piece of fishing line is wound around the sling's axle, which goes over a
pulley to a counterweight. The counterweight gives the force that returns the
sling. The "stop" on the sling pivots down as the sling starts turning, to allow
multiple turns of the sling. Friction must be kept to a minimum for the
maximum amount of turns possible in the sling, so there are ball bearings in the
sling axle, the pulley, and in the "stop".