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Click Photo For Enlargement (101 Kb)
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The track is assembled by sandwiching a 4 inch wide slice from a treadmill belt
between the inner and outer treads, which are secured using four 1/8" aluminium
rivets per tread. A scarf joint is used to connect the ends of the belt without
overlapping it, since that would prevent the belt from bending easily.
Six treads span that joint, each of which are glued using polyurethane glue
to help reinforce the joint.
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October 26, 2003:
The Tiger-1 has the "coolest camo scheme" according to Shain Tyng
(age 14). The new track system went through the entire weekend of
battling without any problems. All of the molded interior treads
were fully intact and all of the exterior oak treads showed little
wear from the hard dirt battlefield. Most battlers agreed that the
Tiger's mobility was significantly improved since the last battle
because of the new motors and tracks.
See Battle In The Badlands for details.
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Click Photo For Enlargement (167 Kb)
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January, 2004:
A new rotate system was installed to increase reliability. The
previous friction-based drive mechanism mounted in the turret
was much smaller, but it
could be rendered ineffective by slimy paintball juice. The new
system uses a strong geared motor and a roller chain mounted under the
top deck of the hull.
Any wires that need to come down from the turret into the hull of the
tank can be fed through the center of the turret sprocket. Currently,
that only includes two small sets of servo wires to control the
elevate and trigger servos.
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The rotate motor consists of a strong gearhead motor and a pair of
right-angle sprockets that allow the motor to be mounted horizontally.
A 10-tooth #35 roller chain sprocket is used to drive the 30-tooth
turret sprocket, providing a slower and more accurate turret rotation.
A 20-tooth turret sprocket can be substituted if additional speed is
necessary.
Evidence of a new welding career can be seen in the homemade mounting
bracket. It certainly isn't the prettiest weld ever made, but it's
strong enough for the purpose.
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Click Photo For Enlargement (120 Kb)
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Click Photo For Enlargement (332 Kb)
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February, 2004:
A new drive system is installed that includes a pair of EV Warrior
drive motors operated at 12 volts and a 9-to-1, dual-stage, #35 roller chain
transmission to provide optimum power and speed. Since the Tiger-1 uses
a friction-drive track system, no "slippage" is needed in the drive system,
allowing chain to be used for the transmission. This reduces the load on
the motor axle bearings (because to heavy tensioning is needed) and increases
the efficiency of the drive system. Two pairs of 10-tooth and 30-tooth
sprockets provide the reduction needed for each motor. Sprockets are mounted
to the motors using spring pins and to the other axles using keys and set
screws.
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The EV Warriors were purchased along with the mounting brackets that
were originally used to install them on a bicycle. The large steel
straps are perfect for holding the motors without blocking the cooling
holes. A metal plate was welded to the strap so that it
could be securely bolted to the bottom of the drive system assembly.
Simply position the motors so that the chain tension is just right and
drill two holes.
Here are the EV Warrior specifications:
| | 12v | 24v |
| No load RPM | 2210 rpm | 4480 rpm |
| Peak Horsepower | .378 hp | 1.55 hp |
| No load current | 2.6 amps | 2.6 amps |
| Stall current | 99.2 amps | 198 amps |
| Stall torque | 691 oz-in | 1,400 oz-in |
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Click Photo For Enlargement (123 Kb)
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Two 2x2" inch muffin fans (from a surplus
catalog, of course) are mounted between two pieces of plexiglass to
circulate air around the motors. Although not absolutely necessary,
it never hurts to keep the motors cooler to increase reliability. Muffin
fans draw very little current, so they are always on whenever the main
power switch is on. The low hum also serves as a nice reminder that
the power is active in the tank.
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April 25, 2004:
The only way to truly determine if a winter's worth of modifications were
beneficial is to take the beast out onto the test field again. As can
been seen in this field test video
the new drive system (3rd generation) and improved track system
(4th generation) worked great. The Tiger has plenty of speed and power, and
is more durable than ever before.
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Click Photo For Enlargement (160 Kb)
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June 2004:
During the Maryland Massacre,
the Tiger gets into the desired firing position, using a small pine
tree for additional protection.
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June 2004:
It doesn't get any better than this ... two tanks battling it out
in close quarters in the thick underbrush.
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Click Photo For Enlargement (188 Kb)
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