Motor Brushes Stuck - Singer 201-2
We got another 201-2 in pretty nice shape. It needed a bit of cleanup and oil, but the machine turns nicely. Since the cord and controller were still installed in the cabinet outside, we just turned it by hand in checking it out.
(Second 201-2)
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When it was time for a sewing test and we went to hook it up, we found that the motor wouldn't run. A quick look at the wiring didn't reveal any problems. I got a meter to check continuity between the power connector and the brush tubes. When I went to remove the brush caps to measure, only springs came out. No brushes.
(Cap & Spring)
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The brushes are supposed to slide inside of square brass tubes, picking up current from the brass tubes. The brushes are pushed against the motor contacts under slight pressure from the springs.
Its difficult to see, but we finally determined that the brushes were still in there. For the photo below, a lot of light was used. I was holding a small flashlight in one hand and the camera in the other. The photo makes it look like the brushes are close to the top. They're not. They are probably 1/2 inch or so down.
(Stuck Brushes)
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With the brush caps off, I measured with the meter. The good news is that there is continuity between the power connector and both brush tubes, so the wiring is OK. We started thinking of ways to get the brushes out.
What we read on the internet suggested that you need to take the motor apart to get stuck brushes out, something I'd like to avoid. Maybe I took it as a challenge, but soon we were talking about sticky tape. We had a roll of it, so I thought I'd give it a try.
This is the setup. A 1/8 x 1/8 inch piece of the tape was placed on the end of the stick. I sanded the end of the stick smooth for best possible grip.
(Stick & Tape)
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I've shown the product that we tried. The printing isn't that clear, so I'll repeat it here in case it's hard to see. The product name is Double Sided Foam Mounting ROLL - Extra Strong Double Stick Tape. In the upper left it says Super Glue Corporation, the manufacturer.
The first attempt failed. The tape used up all its stickiness on graphite dust. Learning this, I cleaned the exposed surface of the brushes with a Q-tip and alcohol before trying the extraction again.
This tape seems to start to set after a few minutes, so I allowed time for the tape to adhere to the stick. After 15 minutes I carefully pulled the paper off the other side and placed it into the brush tube, in contact with the brush surface. I left it in place for a few minutes. I positioned each hole upward for this waiting time, then turned it upside down for the attempted removal.
(Removing Brush)
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With each side, I gently pushed and pulled, trying to loosen the brush. Going by feel, it seemed as if the square part of the brush had to align with the square tube. At a certain point on both sides, the brush pulled easily from the tube. The two brushes are shown below.
(Brushes Out)
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Maybe this can work for others as well, if they ever encounter this unfortunate situation. Now, we'll get some brushes in there and get it going. These machines certainly have a nice feel to them. Even turning them by hand.
John