M4a1 Walker Bulldog Progress, Part 3

I've been working on my Walker Bulldog and I have made a few more progressive changes to the model. Later today I am going to finish painting the wheels once and for all so that the job is done. I installed the antannae bases and I was not satisfied with the plastic antannae. To fix that problem, I cut off the plastic antannae and drilled a hole with my pin vice. I then inserted some steel rod I had laying around that was already black in color. The result is that the tank looks much more realistic to me.



I also went ahead and installed the 50 calibre machine gun. I wanted to iron out how I wanted it to be positioned and I went ahead and did that. I also pin viced (very carefully) the exhaust holes near the barrel of the browning. All that's left to do is repaint the top of the browning because I used a sharp x-acto knife blade to get rid of a protruding seam left from the injection molding process.

I called up an old buddy (a fellow engineer) to confirm I had the right circuit set up for a lighting system. I said "what the heck" and decided to include the lighting system, so I did go out to Trains and Lanes as I had claimed before and sure enough they had fiber optic. The system runs from a 9 volt battery. I chose a 9volt because I already had a couple of pieces that would fit on top of 9 volt batteries, and figured it would be less of a hassle. By the stats on the LED package, the LED will take a maximum of 4.0 volts with the current at 20mA. I used this data to find out the internal resistance of the LED and then proceeded to find what value resistor I would need to wire in series so that it could eat the other 5 volts. I came up with 250ohms. I searched my resistor stash and found a 256.7ohm resistor. Perfect!

All that's left is to carefully play with the fiber optic and paint the portion outside of the hull. I have a switch wired in series so you can turn the lights on and off, but unfortunately to my dismay I found out that it was a push-in button one. That means that I can press the button to light the tank, but I have to hold the button in. Until I decide on a replacement it will do- the 9volt battery should last virtually forever (if left on continuously, it would work in upwards of 30+ hours). The tank will be neat with LEDs, maybe I should have purchased two red LEDs and did the rear lights? Nah, I am satisfied with what I have.