Robotix Toy from the 80s - Motor Repair


  #1  
Old 07-05-20, 01:39 PM
M
Member
Thread Starter
Join Date: Jun 2008
Posts: 12
Upvotes: 0
Received 0 Upvotes on 0 Posts
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.


 
  #2  
Old 07-05-20, 03:26 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,634
Received 4,088 Upvotes on 3,671 Posts
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.
 
  #3  
Old 07-06-20, 06:07 AM
M
Member
Thread Starter
Join Date: Jun 2008
Posts: 12
Upvotes: 0
Received 0 Upvotes on 0 Posts
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.
 
  #4  
Old 07-06-20, 06:30 AM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 14,425
Received 899 Upvotes on 760 Posts
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.
 
  #5  
Old 07-06-20, 06:50 AM
M
Member
Join Date: Sep 2019
Location: Canada
Posts: 1,966
Received 297 Upvotes on 267 Posts
Your first picture shows the connection points to the motor.
Measure across them.
 
  #6  
Old 07-06-20, 08:50 AM
pugsl's Avatar
Forum Topic Moderator
Join Date: Mar 2008
Location: United States
Posts: 8,161
Received 77 Upvotes on 70 Posts
Are the batteries in right? They might all point in same direction, not usual but have seen it.
 
  #7  
Old 07-06-20, 12:33 PM
M
Member
Thread Starter
Join Date: Jun 2008
Posts: 12
Upvotes: 0
Received 0 Upvotes on 0 Posts
pugsl good suggestion. I did check that the batteries were in correctly.
 
  #8  
Old 07-06-20, 12:39 PM
M
Member
Thread Starter
Join Date: Jun 2008
Posts: 12
Upvotes: 0
Received 0 Upvotes on 0 Posts
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!
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: