Robotix Toy from the 80s - Motor Repair


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Old 07-05-20, 01:39 PM
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Robotix Toy from the 80s - Motor Repair

This is probably a weird one. There was a toy made back in the 80's by Milton Bradley called Robotix. It was essentially a builder set, but it came with these small electric motors so you could design stuff to move! It was pretty rad for the time. My Mom pulled my old sets out of the attic a few weeks ago with the thought that my boys would love to play with them. Everything in the sets look to be working except for the motors. I've tried all of them. I loaded brand-new batteries into the battery box. Connected that to the switch panel, and several leads from the switch panel to the motor. I'm measuring 3+ volts at the solder joints right at the armature. So I think everything if fine downstream from there. I saw a Youtube video showing someone opening up the motor and giving it a spin before it came to life, but that did not work for any of my motors. I've opened all of them, checked the gears, the armature and they all spin freely. But no life. Not even a sound. That's as far as my knowledge goes with electric motors this size. Just wondering if anyone out there had any ideas for me to try before I pack it up.


 
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Old 07-05-20, 03:26 PM
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You've got four batteries in the pack. That should be 1.5v x 4 = 6vDC.
It looks like the battery contacts have corrosion on them.
That would be an indication that the batteries were left in and leaked.

Try cleaning up the battery contacts first.
 
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Old 07-06-20, 06:07 AM
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PJmax
The contacts definitely had some corrosion on them. I cleaned them up with a wire brush before I put the batteries in. The rocker switches show +3v in one direction and -3v in the other direction. I was thinking that perhaps each side of rocker gave you half the total load. But you might be right. That would explain why all 5 motors aren't working. I'll take another look at the contacts and see if I can clean them better. Thanks for the help.
 
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Old 07-06-20, 06:30 AM
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I see three wires in the battery pack. Two at the bottom and one at the top. The way it is wired makes me think it is supposed to be 3 volts, not 6 volts.

With such a small voltage and little corrosion will prevent the motor from running. I would clean everything up as PJ suggested. It's hard to believe all the motors would crap out.
 
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Old 07-06-20, 06:50 AM
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Your first picture shows the connection points to the motor.
Measure across them.
 
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Old 07-06-20, 08:50 AM
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Are the batteries in right? They might all point in same direction, not usual but have seen it.
 
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Old 07-06-20, 12:33 PM
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pugsl good suggestion. I did check that the batteries were in correctly.
 
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Old 07-06-20, 12:39 PM
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manden those were the solder joints I referenced. I'm seeing 3+ volts across them. So I guess it really comes down to "what is the expected voltage?" As Tolyn Ironhand mentioned, I figured with the 3 wires coming out, I should see half voltage on each side of the toggle switch, with one side sending pos and other neg. That is what I'm seeing at solder joints and in the end of the yellow wire as well.

I'm going to try to clean things up again and see if that makes a difference. Will let everyone know how I get along tonight. Thanks for the help so far!
 
 

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