Moving machine gun

[Dennis Jones]

For those builders like me who have only got a 6 channel Futaba TX and are left with channel 5 as a spare, this channel is just an on/off channel and reverses the polarity of the outputs on the aux module. I have devised a way of moving the m/c gun side to side using an old servo and some bits out of the scrap bin (not pretty I will admit). First of all I took the electronics out of the servo including the pot, which just leaves the motor and gears. Cut off the stop that prevents the output arm going 360 degs. Mount the servo roughly as shown so that when the output arm is rotated 360 degs the barrel swings from left to right and back again continuously. To control the motor I inserted a 7805 5volt regulator chip to supply the motor with 5volts, I put 34 ohm (2 - 68 ohm resistors in parallel) in series with the 5volt supply to the motor to slow the movement down a bit. The input to the chip comes from the 24 volt output from ch 5 on the aux module. I put a diode 1N4001 in series with the 24 volt supply to the chip so that when the polarity is reversed by channel 5 the supply to the chip is stopped and the motor stops. It may seem a bit complicated but it used a spare channel if it is not being used by anything else, it would be easier if it was a prop channel.
I also have put a hi bright led in the end of the barrel for firing.

Dennis.

[phil fitzpatrick]

Hi Dennis
Welldone with your MG movement.
You have inspired me to have a go,I've got some servo's saved from
some hard landings when learning to fly my Helicopters.
You have further inspired me to continue to save more scrap and rubbish
for future use.
I am using the scrap Brass from the Panzer 111L kit to make detail parts
for my Comet,as I did with the Panzer.
Have just recently made a part for the front drivers Port Latch out of a steel
support to some filing trays at work, and used some thin scrap galv
sheet from behind a guilotine at work for fiiting out the rear panier.
Cheers
Phil

[Nick Farrugia]

hello dennis
nice job on the gun movement,and all from bits of scrap most satisfying
good job
all the best
nick