R/C Tank Combat

Tank #T036


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Type: Valentine Mk IV Armament: 40mm
Built: October 2004 Armor: 65mm
Builder: Jon Kowitz Rating: 30/3
Status: Under Construction Battles: 0
Owner: Jon Kowitz Points Earned: 0
Call Sign: Be Mine Points Given: 0
  • 1/4" plywood body on a 3/4" box steel frame
  • Replicated Vickers "Slow-motion" suspension system
  • FWW motor system (aka: Ford windshield wiper motors)
  • Lightweight TTS with plywood drive sprocket
  • Two-speed Tri-Pact speed control
  • September 2005 or bust!!!

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    When I started this guy I was stuck with almost no money to do it with and a pretty limited selection of motors to do it with. This steel frame will carry all of the vehicle's weight and motor torque so I can hopefully lighten up the rest of the hull considerably to save weight. We'll see how it turns out.

    The Valentine's suspension system was called a "Slow Motion" type when patented by the Vickers corporation. I figured that this is probably as good a replica as any and should be solid enough to withstand any kind of forces that this machine can generate, yet still allow the roadwheels to articulate to accomodate any terrain it's rolling over to maintain traction.

    A good example of loss of traction is in the video archives where the Hetzer gets one corner up on a rock which leaves very little of the track in contact with the ground. We'll see how well it works.


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    Here's the jig I made to cut out the roadwheels and belt pulleys for the project. Keeps my fingers well away from that saw blade which suits me just fine.

    Coming along, we now have all of the roadwheels installed and the motor/transmission box partially assembled. It was at this point that all of my friends started taking the project seriously. The track tensioners are spring loaded which should (in theory) maintain proper track tension regardless of what the suspension is doing.

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    Another shot of the "Slow-motion" suspension with the roadwheels installed. The Val uses two rows of track guideteeth to hold the track under the suspension so only one wheel is installed on each axle instead of the usual two.

    One good look at my motors and you should realize why I'm weight paranoid with this project. These are late model Ford windshield wiper motors, selected because they are cheap, are readily available, and can be found in a wide variety of Ford automobiles and trucks. One of the biggest drawbacks so far will be speed. Motor shaft RPMs are a paltry 120 RPM which will make this a slow beast no matter what I do. Over-volting may be my only option eventually but we'll stick with a safe, 12v system for now.

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    The difference three weeks can make. Tracks are on, electronics wired in, and the rest of the drivetrain assembled. As you can see by the battered trackpads I've already had a bit of fun with the beastie. Top speed is a modest 3-4 mph (about the speed of a brisk walk), which gives it a scaled speed of 18 - 24 MPH, which beats the full size version's 15 MPH pace anyway (lol). My track tensioning system isn't working out, allowing the track to jump on the sprocket when under duress (aka: trying to turn in grass) so I'm thinking about replacing the springs with a turnbuckle which will hold the tension a bit better (I hope anyway).

    As a bad housekeeper says, pardon my mess (lol). Most of the electronics are going up in the turret (which obviously isn't assembled yet) so it kinda got piled on the bellypan somewhat haphazardly. The single 12v, 15 AH motorcycle battery sits up front and is secured by the cargostrap located there. Although it sounds small (and it is) my tiny motors actually pay off somewhat. That tiny battery powers the beastie for about 90 minutes of brush-thumping, stump-climbing fun.

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    I personally never thought that I'd be able to cut a workable sproket out of a sheet of plywood, by hand, and have it work at all, let alone as well as these work. The second one I made does work a bit better than the first, but both hold onto the track quite solidly. Only times it jumps is when the tensioner gets pulled back, slackening the top part of the track. That'll be worked out soon enough. Unfortunately I don't have any pics of the track being assembled but it's made from two, 1" nylon straps like is used for a dog leash and 3/4" wide strips of 1/4" poplar wood. All glued (shoo goo of all things) and braded together into a fairly resiliant track. I've lost a few guideteeth from thrown tracks but those don't seem to be effecting performance any.

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