Month's Goal: $300, Received: $90.00 - (30%) Contribute Now
Donate whatever you can or Join the 15,000 other NAWCC members for only $72 (plus $10 for hard copy publications). Check it out here.


NOTICE Notice: This is an old thread. The last post was 817 days ago. If your post is not directly related to this discussion please consider making a new thread.
Results 1 to 5 of 5
  1. #1
    Registered User
    Join Date
    Sep 2011
    Location
    Fitzwilliam,NH
    Posts
    18

    Default Seth Thomas Sangamo Motor

    I have 2 Seth Thomas Electric clocks with Sangamo Motors that do not work. I've checked the wiring when I test them there is some resistance- they try to start but they just don't run.
    The question is can the A300-100 motor available on Timesavers be used as a replacement. I would have to somehow get the gear off the Sangamo and put it on the replacement.
    Other than that are there any other options?

  2. #2

    Default Re: Seth Thomas Sangamo Motor (RE: paulo)

    A picture of your two Seth Thomas electric clocks that refuse to operate and especially a close-up picture of the Sangamo motors would help identify which of the many Sangamo clock motors are installed on the clocks.

    Actually, Paulo, the motors may not be the cause of the clock not running. The mechanical load of the clock may be too much for the tiny Sangamo electric motor to handle. You might try giving the gear that the motor pinion drives a little "push" with your finger to see if a little help gets the motor going.

    Photos please.
    H.J. (Les) Lesovsky, Alhambra California

  3. #3
    Registered User
    Join Date
    Sep 2011
    Location
    Fitzwilliam,NH
    Posts
    18

    Default Re: Seth Thomas Sangamo Motor (RE: Eckmill)

    Thanks for the reply- Both motors are identical to this pictures in this thread:

    http://mb.nawcc.org/showthread.php?3...o-motor-repair

    I bought the second clock to use as parts. I've tried giving the motors a push and they sometimes seem to want to go but then do nothing. I took them both out of the movements and inspected and cleaned where I could still nothing. I can feel some resistance but not enough to move them. I may try the suggestion in the thread of remagnetizing the rotor but if a replacement where available then I try that.

  4. #4

    Default Re: Seth Thomas Sangamo Motor (RE: paulo)

    As far as I am aware, there is no replacement motor for the type shown in the reference. I read that the Seth Thomas location where parts for that movement were located was destroyed by a flood years ago. Rebuilding the bushings in the motor and especially the bushing in the clock plate is the obvious solution. Re-magnetizing the synchronous rotor as described is important as well if the motor fails to run after the bearings are re-worked.
    H.J. (Les) Lesovsky, Alhambra California

  5. #5

    Default Re: Seth Thomas Sangamo Motor (RE: paulo)

    Paulo - This is the best motor ST used for this job. Retrofit to any other type will be a downgrade in durabilty, performance, quality, and a increase in noise in use. Be certain you have removed the tiny ball bearing in motor end oil cup, very often even with thorough cleaning it will remain stuck in place with congealed motor lubricant of any type. I use a controlled shot of a very strong solvent such as automotive brake parts cleaner or 'Gun Scrubber', its small application tube is ideal to concentrate the shot in to the bearing area rather then flooding the entire assembly which might damage the electric coil potting materials. Once applied, use a straightened paper clip stuck to a very strong magnet, such as a screw holding screwdriver magnet, and fish around in the sink until the ball bearing sticks and you can pull it out. Then clean all, use strong light and a high power loupe to examine and make certain the sink is absolutely clean. Peg out carefully but make sure you do not break off a toothpick or any pegwood down that hole, hard to cleanly extract (how well I know). If you can see or feel any wear whatsoever on the tip-ends of the rotor arbor, dress it off but do not remove a lot as a lot of installed endshake is undesirable. Use a light lubricant not sensitive to heat, such as automotive transmission fluid, but just a few drops. I do not know what your mains voltage is where you live, but if you are using a transformer to reduce to 110v, be sure the voltage available to run this motor is nearly 110v or better. I have experimented with some of these using a variac which is a variable auto-transformer, the Sangamo motor even in perfect shape will not start reliably below about 90v measured, which is not indicative of malfunction. That aside, these motors start easily, never start backwards, and run very quietly if you lubricate as discussed, and then after being sure of the result in your motor service only then sparingly apply light grease such as yellow Moebius to the brown micarda first wheel teeth. Will provide many years of good use. CW

    Last edited by coldwar; 05-29-2012 at 11:19 AM. Reason: spelling

Similar Threads

  1. Seth Thomas / Sangamo motor repair
    By bmp84414 in forum Electric Horology
    Replies: 8
    Last Post: 03-10-2014, 11:32 AM
  2. seth thomas electric motor needed
    By pete@Treasury of Time in forum Clock Repair
    Replies: 4
    Last Post: 09-01-2006, 11:37 AM
  3. Seth Thomas Electric motor??????
    By DML Clocks in forum Electric Horology
    Replies: 16
    Last Post: 04-27-2006, 05:56 AM
  4. Seth Thomas Electric motor??????
    By DML Clocks in forum Clock Repair
    Replies: 7
    Last Post: 06-08-2003, 11:37 AM
  5. Seth Thomas Electric motor??????
    By DML Clocks in forum Electric Horology
    Replies: 1
    Last Post: 06-04-2003, 11:53 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •