Here's a shot of a drive assembly mounted in place. It's made up of
stacked laminations of 3/4" ply. The motor swings on it's mounting
piece to tension the drive belt. The belts and pulleys are 3L series
(3/8" wide belt) components. The PowerTwist belt can be easily changed
to different lengths while I test different pulley size configurations.
In the background can be seen the two Dentronics MD03 motor controllers.
In actual practice these controllers have not worked as I had hoped.
They are self limiting to 20amps and this appears to be limiting T005's
mobility on the first couple of test runs. I'll be upgrading to a relay
based system in the near future. The controllers are mounted on a hinged
piece that holds the batteries securely in place. Tiger Killer
can mount two 12volt 17 amp batteries or two smaller batteries.
A shot of a drive assembly on the bench.
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Click Photo For Enlargement (68 Kb)
In this shot you can see the 9 tooth drive sprocket which protrudes outside
the hull when mounted in place. The bearings used are non-precision press
fit roller bearings that are used in wheelbarrow wheels and such. You can
get them at mower repair places and well stocked hardware and farm supply
stores for a couple of bucks apiece. You won't find them at Home Depot.
A word on my motors. They are Minertia brand servo motors that I scavenged
out of some old printers several years ago. Their rated at 22.5 volts and
have good torque when connected directly to a battery. Not so good when
running on those MD03 controllers.
Here's a close-up of the turret base plate.
Click Photo For Enlargement (63 Kb)
Click Photo For Enlargement (54 Kb)
The turret mounts to the hull with three custom grooved rollers mounted on
the underside of the turret. The grooves wrap around the edge of the
circular cutout on the top of Tiger Killers hull.
They were cut out of some
2" nylon stock by the Frank Lathe Master Pittelli. My daughter donated
some old roller blades (with their bearings) for the cause.
The turret is rotated with a friction drive. The rear roller has rubber
tape wrapped around it and is driven by this 24volt gear motor. So far in
tests it works pretty well.
Click Photo For Enlargement (63 Kb)
Click Photo For Enlargement (61 Kb)
The turret drive roller is spring tensioned by this setup. As a side note,
this turret mounting system I came up with gives you the ability to easily
remove the turret from the tank. I can foresee using this feature to use
the turret in a fixed bunker emplacement or even in another hull.
The T-34 is prepared for its initial field trial at the Tri-Pact Proving
Grounds with a fully operational drive and track system.
Click Photo For Enlargement (135 Kb)
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At Home!!! The T-34 moves through the snow just like it's full-scale
cousin. The treadmill belt track system has no problem getting traction
in the snow, although the drive system is under-powered for the first
trial. Once that problem is resolved, it's time for a winter battle.
