Here is the complete set of RC electronics I am going to use in the model. The blur thing is the Servo, the little white gear on top it made to spin continuously left or right. perfect for the turret. The grey-white thing with the prongs is actually the entire radio reciever! 3 channels, even! And the yellow/green thing is obviously the battery. Except for the battery, these things are tiny. How tiny? well, lets compare it to a QUARTER.
Thats tiny. I'm sure I could find a way to fit these inside a model tank, no?? The blue servo was an extra part, and the reciever is one I went and bought just for this... dont be alarmed! Guess how much it cost; $20.00! This stuff has gotten seriously cheaper over the years (I remember a reciever was over $80), yet the radio transmitter is still pretty pricey. Now, as some may know, servos for these things dont normally spin continuously... they only move about 45 degrees in each direction. After doing some research online (yay google!) I found out how to modify them to do what I wanted.
Heres a closeup (same image from the one before.. yay 4.1 megapixels!). now, if you look carefully, on the right youll see a metal can: thats the motor itself. The top half is the gearing, the bottom left is the potentiometer that controls everything.... the thing in the middle- under the bottom left line of the X. is something that doesnt belong there: a resistor. Its not too difficult of a modification: you open it up, disconnect the 3 wires of the potentiometer from the mini circuitboard, find 2 closely matched ohm value resistors (I used 1k.. matched means you get a meter and find 2 that are close.. resistors are never perfect: +/- 10% or 5% of its value is what it actualy is so you have to test them).. and hook those resistors to the potentiometers' connection points in a V shape. pretty much as simple as that.
So, with the parts all ready, the mounting of it all was pretty simple and Zen... I just jammed the drive gear into the botom of the turret disk, and glued styrene bars on either side of the servo to keep it from spinning. Simple as that: the gear-turret connection was the only attachment. I did it this way after several experiments, and found that the servo had to be 'rockable' and loose in order to keep the turrets motion smooth. It needed to be sloppy, and bolting anything down would only result in things binding up and simply not working. The reicever was mounted directly to the side of the servo box with sevotape, meaning that the entire thing was a tight little bundle with only battery wires coming off of it... all tucked up nice and neat under the roof plate. So, just make room for the battery, keep the area under the roof plate clear, and that part of the job is DONE already!
Next comes the lighting and the radar spinner. So, some details: the quarter sized thing wrapped in tape is a 3v watch battery, which tucks into the sidewall gap out of the way. The red block is a disconnect plug so I could remove the top from the bottom wires. Lets see... on the roof section to the left you can see the leds, both white and red, which will also be tucked into the sidewalls. The white rectangle plastic thing on the roof is the radar spinner, story and closeup on that later. Inside the open side door cavity (by the battery) is a slider on/off switch connected to this little side circuit.. I needed an on/off switch that could be easilly accessed without tearing the whole thing apart... what kind of model would that be?!? Lastly, there is a wavy-square hole cut into the right side wall of the interior. This was to make room for the battery to fit in crossways... this was pretty much the only place to fit it, as it turned out to be larger than first figured (the problem with dealing with things so small, so small in fact that the entire tank can fit in the palm of my hand, remember). You will see the battery in place in further pics as well, so lets move on.
OK, here is a bit that I am a little proud of and creeped out by: The radar spinner. One day One of my neighbors was throwing away a broken CD-ROM drive, and I offered to take it so I could tear it apart (some fevered dream of putting its laser to use.. no way). As I tore it apart out of simple tinker curiosity... I found the mechanism that powered the tray in and out of the drive... it was a teeeny little motor with a built-in wormgear, and a track on the tray. In between was a normal gear that meshed them both together... Interesting. I know from building PCs that they ran on both 5v and 3v DC, and that that teeny little motor was one of the two. Eagerly ripping it out, and connecting it to a 3v battery, it spun! eureka! 3v motor it is! PERFECT! This was all in a mad energetic frenzy that took place in about 10 minutes' time. And thats where I got the creepy from... I was a mad professor- that guy from robot chicken... or a seriously tweaked out individual. WHEW! anyways, it was a simple matter to glue the gear onto the radar base, then test fit and glue the wormgear motor in just the right angle... an axle was required, because this sort of setup does NOT need slop (the radar would often get flung off, and rattle all over the place). Add it to the wiring for the lights, and done! Most of the effort after this was cleaning up the wiring and making it all fit together seamlessly.
Thats the advantage of this particular model... once you glue the gears and side panes in, you really dont have to glue anymore, and let it just fit together like some chinese puzzle.
This shows the final arrangement of everything. All that is needed is to plug the batery in, and put the roof on. all the work making it seamless really pays of, and it just sorta clicks in place! You can see the battery installed, and the servo electronics all tucked up under the roof plate, the watch battery tucked out of sight. Just flip the roof over and..
A tank! packed full of electric (not sure if its electronic) gizmos and goodies, yet none the wiser. I can play this in a game on the tabletop. then at one point, take out my Futaba radio, and suddenly:*Sigh*.. that makes it all worth it!!
Here we have a frontal view, showing the headlights that were painstakingly hollowed out, and yes the LEDs are direclty behind them.... but unfortunately, I am unable to power this side circuit up... its battery is dead. In time I'll have it running and have another video edited in here.
Thats it for this old project. Sad to say, that this model was also abandoned and left to collect dust as soon as it was finished.. shame on me!! And now... yep now I can say Im caught up in the history speech, and can now get to what I'm currently working on: The new servoed Hammerhead!
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