The motor this platform uses can be control by any means. I use an cheap RC car to control the motors.The gear box and motor combo can deliver different gear ratio settings to suite your application. The gear ratio I use is 114.7:1 @ 4.5V. This ratio work well with the remote control that I use. I have try other ratios but this over heat the transistors on the RC board.
The this Tank platform use two motor so it use skid steering to turn. So you need least need a two channel RC car to make this project but most RC car have at least two channels anyway.
I will show both the new and old design. The old design will be known as Mk1 and the new design Mk2.
Step 1: Tools and Parts
1. Double Motor Independent 4 Speed Gearbox / Axle Assembly Tamiya ITEM 70097
Jaycar Cat no. YG2741 $22.95
2. Tamiya Track & Wheel Set (You need two if you want to build Mk2)
Jaycar Cat no. YG2867 $16.95
3. 2 X Tamiya Universal Plate Set
Jaycar Cat no. YG2865 $8.95
4. M3 stand off posts 25mm
Jaycar Cat no. HP0907 $5.95
5. M3 bolts
Jaycar Cat no. HP0400 $2.50
6. M3 nuts
Jaycar Cat no. HP0425 $2.95
7. Cable ties
Jaycar Cat no. HP1200 $1.85
8. 3 by 1 AA battery holders
Jaycar Cat no. PH9203 $0.95
9. RC car any will do mine cost me $20
10. Switch on/off
Jaycar Cat no. ST0300 $2.95
All prices in AUS$
1. Philips Screw Driver
4. Soldering Iron
Step 2: Control Board
The control board has two wire that go from the steering motor and to the drive motor. These get solder onto the new motor in our gearbox. I put left and right signals onto the right motor; forward and reverse onto the left motor.
When you turn on the board, you may found that the motor is going the wrong way just swap around the two wires going to the motor.
There are other ways to power and drive these two motor but this a simple and fun way of doing it.
Step 3: Details in Wiring Board
Step 4: Fabrication of Gear Box
Step 5: Fabrication of Base
Step 6: Road Wheels and Idle Wheel Assembled for Mk2
Mk2 is a little more complex. You need four right angle flanges. The two these are cut down so we can fit an extra pair of road wheels. Then I screw them to the base, then the idle wheel flange get screw to the base as well.
I use the extra wheels in the second kit to make enough wheels for this new design. I use four pair of road wheels. The idle wheel is the same size as the rear sprocket and road wheels. Now that does both plat form.
Then you insert four rods into the right angle flange. Then you install three of the larger road wheels. Then repeat for the idle wheel, which use the same size wheel as the road wheels. The sprocket is then place on the motor output shaft.
Step 7: Road Wheels and Idle Wheel Assembled for Mk1
Step 8: Tank Tracks
All you do is place the tabs inside the the hole of the next tracks. Then you repeat until done the full length of track. Then you place track over the idle wheel and sprocket. Then you pull track around the road wheels. Then you check to make sure that the track has enough play in them.
Installing them is easy. I place the tracks over the drive sprocket and idle wheel. Then grabs the bottom of the track and drag under the road wheels.
After I install both set of tracks. I just check the tension of the tracks. As shown below this track has pass. You can move the motor and gearbox forward or back to increase or decrease tension on the tracks.
Step 9: Installing Battery Pack
The you wire the three AA battery packs together in series and install a on/off on the positive side that going to the control board. Then check with some fresh battery that you have 4.5volt coming out of the battery pack using a voltmeter.
I had to put a stand off because the new control board was larger than I thought. So these battery are on the roof of tank platform. Then the whole roof section get screw onto this stand off.