Gents First foray into electric with a ST Mantel clock...Questions for sure

Clockinit

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Nov 4, 2019
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Hello peoples..this is my first visit to this forum as i didn't think I'd run across an electric clock...But I have..It's a clock that belongs to my cousin, who brought it along with her 'so i could look at it while I'm looking at Mom's (my Aunt) cuckoo clock' I must say, I am intrigued..It's a SETH THOMAS MEDBURY mode...l looks like maybe from 1935, looking at the writing (in pencil) on the case back. It is a #1702 movement, with a SANGAMO motor.With a little bit of wire repair where the wiring comes through the clock case, I was able to get it to run. It seems to chug along just well, However the strikes and chimes are very slow...The pivots seem very dry and in need of cleaning...That being said...my question concerns the motor. The motor came apart easily when taken out of the movement. It appears that the top 'cap' and the motor are just joined by the shaft on the cap that seems to ride on the shoulder of that shaft that spins freely in a 'well' on the center of the motor. The motor housing is screwed to the back of the plate and the cap's outer pivot sits in some type of well/reservoir on the front plate. The cap and motor housing and are held together by the compression of the front and rear movement plates....Does this sound right? My biggest questions are cleaning this motor and especially lubrication...It seems like there was grease on the pivot shoulder and in the well where the cap meets the motor...What is the 'gear' looking pattern at the top of the motor? Is that residue build up" does that get cleaned up/off? ...and lastly, is that a reservoir for lubricant for the pivot at the front plate?? Was that last one a stupid question?... to re-itterate, this is my first foray into this type of repair...so i claim ignorance,,,
Any help would be greatly appreciated!!!
Oh, and I will do a better repair on the temporary wire repair I did to get the clock to run...someone rigged it prior to me getting my grubby little hands on it:=

Bob

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Clockinit

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...Sorry..Typo...That reservoir sits on the outside of the back plate...the arbor with the drive gear end goes thru the plate to that 'reservoir'..I'm just making that word up...What is it called??

Bob
 

Toughtool

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What is the 'gear' looking pattern at the top of the motor?
If you are talking about the first photo, it looks to me like a crimping operation to crimp the brass boss to the plate. The twelve impressions are not related to the hours on a clock. If you are talking about the second photo, not a clue. The rotor is the "U" shaped piece with the shaft through it on the unit on the left in photo 2, The pole pieces of the motor are the tabs on the unit on the right in photo 2. The gear image could be just that, an image denoting the poles of the motor.

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Clockinit

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Thanks ToughTool...that starts me out and arms me with a little bit'o'knowledge...Does that motor get cleaned and or lubed where the shaft goes thru it? And does that shoulder at the center of the coil where the shaft goes thru.... does that get lubed.? It appears as if there was grease on that area....

Bob
 

Toughtool

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Bob, You don't have a photo with the motor installed but, if I understand your text, there is a gear on the motor shaft that meshed with the large black gear, and the shaft extends down below into the chime striker area. I would say the bearings should be lubricated but with what I don't know. I would probably clean the bearings with a solvent and oil with #2 clock oil. But other members here with more knowledge about clock lubricates would have better advice. The motor is probably a synchronous motor and will have a fixed RPM. I noticed it is requiring 60 Hz AC. If the strikers are slow then dirty and caked bearings can slow the motor and cause the motor to run hot. If you assemble it and put a drop of #2 clock oil on the bearings, then see the striker run faster then you need to clean the bearings and shafts thoroughly. The fresh oil will free up the movement but will only be temporary, because the fresh oil will flush the old dirty oil out of the bearings and they will get gummy again.
 

Clockinit

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ToughTool...Thanks for getting back...Cleaning of the pivots and fresh oil sped up the chimes and strike immensely!! As for the motor. That rotor and shaft don't seem as they were staked to the motor. The rotor and shaft seem to just 'float' or hover as it spins around the top of the motor....I put a dab of grease where the two meet, as that's what appeared to be there before. I also topically cleaned the 'gear looking grid on the top of the motor'. It seems 50% - 75% quieter..(not that it's noisy by any means). However, the rotor does seem to have a little wobble in it. That's why I was wondering if that rotor and shaft get staked or not...I tried it, but not too roughly, as not to not damage anything..Are you saying I can clean the hole in the motor with maybe 'ONE DIP' Then put some clock oil in the hole? Seems like it should have add'l lubrication....somewhere for the motor? The motor is chugging along and the clock seems to be keeping good time and chiming and striking very well...

Bob.
 

davefr

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ToughTool...Thanks for getting back...Cleaning of the pivots and fresh oil sped up the chimes and strike immensely!! As for the motor. That rotor and shaft don't seem as they were staked to the motor. The rotor and shaft seem to just 'float' or hover as it spins around the top of the motor....I put a dab of grease where the two meet, as that's what appeared to be there before. I also topically cleaned the 'gear looking grid on the top of the motor'. It seems 50% - 75% quieter..(not that it's noisy by any means). However, the rotor does seem to have a little wobble in it. That's why I was wondering if that rotor and shaft get staked or not...I tried it, but not too roughly, as not to not damage anything..Are you saying I can clean the hole in the motor with maybe 'ONE DIP' Then put some clock oil in the hole? Seems like it should have add'l lubrication....somewhere for the motor? The motor is chugging along and the clock seems to be keeping good time and chiming and striking very well...

Bob.
Most of those motors have two bushings (front and back) with a small reservoir between them. (sometimes lined with oil absorbing felt). If you feel any lateral wobble, you'll need to rebush. If there's no wobble then try a thorough cleaning and then add a lightweight oil in the center reservoir. Don't use grease or heavy weight clock oil. The reasons you see what looks like grease is because the old oil has experienced decades of oxidation. Grease has too much viscosity for these low torque/high RPM clock motors.

You might be able to push out both bushings with a small pin punch from the opposite direction..
 

Clockinit

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Thanks for that Davefr....I'll poke around a bit and see what happens..Dave...I know the pivot on the shaft with the drive gear, that goes thru the rotor rides in that brass reservoir seen in photos 4 and 5. It goes thru the hole/crimped bushing on the inside of the plate, and outside there is a brass cup What is that 'cup'?? On the motor. is that brass center where the rotor shaft goes thru,. is that one of the bushings you're referring to? at the opposite end of the motor is a clear red covering of some sort.Is there another bushing there? Meanwhile, one of the wires coming off the motor broke off where it is soldered to the side of the motor. I'm gonna try getting the existing solder at the point of attachment and meld the wire back on to it...I AM NOT a good solderer-er (huh?) I don't know why I can't get it...sometimes it works...most times it doesn't..I've watched plenty of tutorials...but Alas! I Suck at it!! So I'm going to attempt this repair before I go any further, with getting inside the motor..
Again, Thanks for jumpin'.in and I will let you know what happens..

Bob
 
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