sethcollins
Jul 26, 2008, 03:20 AM
i have always wanted to make a bomb drop for my rc planes. waaaay back when, i was using cassette tape holders glued in to the bottom of my e stick. i probably used the mili vanilli tape of my older sister. i never flew well/long enough to test out that idea, so fast forward 15 +years.
i wanted to make a simple electronic bomb drop that weighs next to nothing, fits on to my profile foamie. not wanting to delve too much into electronics designing circuits and all, i went at it from a hacker pint of view. the solution is amazingly simple!
i used one of my old cheapie 9 gram servos that came with an rtf plane. the first crash stripped the gears on these. no fear since they were so horribly cheap they didn't even have screws holding the housing together.
i opened the servo up and plugged it in to an rx. with everything up and running i turned the potentiometer until the motor stopped spinning.
i cut the wires to the motor.
not having any small gauge coated wire i opened up the motor housing and unwound one of the coils.
also i pulled out the motor shaft since i needed a small metal rod. i could have used a machine screw, cut off portion of motor shaft, or whatever was available, but this was already in my hand.
i left about 1" extra and wound the wire around the motor shaft. 3-400 turns later i had my super mini electro magnet! i put a small piece of shrink wrap around it to hold it all together. i soldered it to the wires that used to connect to the motor.
not having any magnets on hand i used a piece out of the motor. probably not powerful enough to hold the "bomb" on in any wind, but sufficient for a test. i had the servo plugged in to ch 4 on my tx one move left did nothing, but to the right....... bombs away!!!! the magnet shot off the motor pole! sweet!
you can use this to release two bombs just set both bombs with north up and wind the coils the same way, move stick left = drop left bomb. move right = drop right bomb.
i wan;t sure of the draw on my bec some one more ambitious may want to check it out.
i wanted to make a simple electronic bomb drop that weighs next to nothing, fits on to my profile foamie. not wanting to delve too much into electronics designing circuits and all, i went at it from a hacker pint of view. the solution is amazingly simple!
i used one of my old cheapie 9 gram servos that came with an rtf plane. the first crash stripped the gears on these. no fear since they were so horribly cheap they didn't even have screws holding the housing together.
i opened the servo up and plugged it in to an rx. with everything up and running i turned the potentiometer until the motor stopped spinning.
i cut the wires to the motor.
not having any small gauge coated wire i opened up the motor housing and unwound one of the coils.
also i pulled out the motor shaft since i needed a small metal rod. i could have used a machine screw, cut off portion of motor shaft, or whatever was available, but this was already in my hand.
i left about 1" extra and wound the wire around the motor shaft. 3-400 turns later i had my super mini electro magnet! i put a small piece of shrink wrap around it to hold it all together. i soldered it to the wires that used to connect to the motor.
not having any magnets on hand i used a piece out of the motor. probably not powerful enough to hold the "bomb" on in any wind, but sufficient for a test. i had the servo plugged in to ch 4 on my tx one move left did nothing, but to the right....... bombs away!!!! the magnet shot off the motor pole! sweet!
you can use this to release two bombs just set both bombs with north up and wind the coils the same way, move stick left = drop left bomb. move right = drop right bomb.
i wan;t sure of the draw on my bec some one more ambitious may want to check it out.