seth thomas mvmt no. 120

[Carroll Hardin]

A Seth Thomas NO. 120 is giving me trouble--
It would run great for about 2 days and just stop. I noticed the time spring,( enclosed in it's box)was appearing to be rubbing against the wheel. After removing the spring from the barrel
it was obvious that the spring was badly coned and catching on the brad heads which hold the click assembly onto the wheel.The spring had been
previously installed and cut to fit this clock.
A new spring of the correct size was installed and now the clock won't stay running like before.
Any suggestions appreciated.Thanks, Carroll

[Carroll Hardin]

A Seth Thomas NO. 120 is giving me trouble--
It would run great for about 2 days and just stop. I noticed the time spring,( enclosed in it's box)was appearing to be rubbing against the wheel. After removing the spring from the barrel
it was obvious that the spring was badly coned and catching on the brad heads which hold the click assembly onto the wheel.The spring had been
previously installed and cut to fit this clock.
A new spring of the correct size was installed and now the clock won't stay running like before.
Any suggestions appreciated.Thanks, Carroll

[jacks61fd]

Carroll on these movements the bottom halh of the plate that you remove to get the springs and barrels out--the top of this plate screws to the upper half of the front movement plate --the bottom of this lower plate is secured to-I believe to three posts,their are 3 spacers that go on the post before the plate is installed-the spacers are the same thickness as the upper front plate,many times these spacers are not observed when putting the movement in to where ever you clean your movements - check the bottom of where you cleaned the movement- they may also have been missing due to a previous repair. Without these spacers the lower front plate will be cocked over enough to stop the clock after a day or two as the spring winds down- if the spacers are lost I have used clock bushing of the same thickness as the upper plate. JACK

[Bob Vasquez]

Carroll, at the clock shop that I work at, we have stopped taking in this clock for repair. Most of the ones we restored have been comebacks. There comes a time that you just have to make a business decision and move on. Bob V.

[Carroll Hardin]

Jack and Bob,
Thank you for your replys about the Seth Thomas 120 movement. The bottom part of the plate is indeed sitting on three posts. As that part of the plate rests on top of the top half, there is a gap created on the middle post, which has the spacer on it. Guess I will completely dissasemble it and start over. Am determined to fix it, even though there have been previous repairs. They are mean buggers. Thanks.

Carroll /infopop/emoticons/icon_mad.gif /infopop/emoticons/icon_confused.gif

[jacks61fd]

Carroll
All three post require that same spacer that is on the center post. The way it is now you are pulling the ends of that lower plate down and this will cause the loss of power you are getting after a couple of days. JACK

[gre406]

Hello Carroll...Good luck with that ST-120..This might be of interest to you..

http://userweb.nni.com/gre406/Lyons5.jpg

I should have seen that first off but..Oh well!!
Sometimes fixing other "peoples" fixes take longer then a major overhaul..

Geo
NAWCC#78594

[Carroll Hardin]

Geo.

Thanks for the 120 Pic, but I didn't get your comments. The spacer is on the bottom center post but spacers on the other two would be detremental would they not?
Thanks,

Carroll

[gre406]

Carroll..Jack said there should be three washers..Take a look and make sure the "sub-plate" is flat when together...Probably not with only one washer...I forget..

I was saying to look at the "snail" hitting the "rack" at the three o'clock position..This stopped the clock everyday..Check and make sure yours is not touching at that position..

Geo
NAWCC#78594

[Carroll Hardin]

George,

Thanks again for your reply about the 120. The shadow on the pic kinda hid the snail so I didn't realize your thoughts on this. I hate to beat this to death, but I have a spacer on the center post, which raises the bottom of the plate even with the top part of the bottm plate. The top and bottom of the lower half of the plate now measure the same in between, so I don't see how any binding happens there. My opinion is that a spacer on all three posts would just re-create the problem of binding.
Thanks to all for your comments and help.

Carroll

[jacks61fd]

Carroll
Unless someone replaced the outside post with longer ones spacers are required on the outside post as well JACK

[jacks61fd]

Carroll
Here's a test you can try - with the movement assembled the way you have it with a spacer just on the center post and all the springs let down check the end play of each winding arbor I think you will find end play(shake forward and backward between the plates) on the center arbor and much less or none on the outer arbors,then loosen the two nuts on the outer post and see if you now pickup end play if you do you need those spacers JACK

[gre406]

Phil...A combination of the close clearance, the wearing of the minute staff bearing and it looks like it was flattened during a re-staking process..The pin was square to the plate..

http://userweb.nni.com/gre406/st120.jpg

The good news is its been returned to the owner and is running fine now for 3 months...

Geo
NAWCC#78594

[gre406]

Carroll...CORRECTION TO PREVIOUS POSTS..

I am sorry for mixing up the ST 124 movement and and the 120 movement...Maybe Jack did the same...

This is the 120 movement..Correct???

http://userweb.nni.com/gre406/Seth120.jpg

It looks to me as there should only be one (1) washer on the post..

You may want to remove the verge (easy on this movement) and wind only one or two clicks of the time train to check motion...

Sorry for the mix-up..

Geo
NAWCC#78594

[Dick Feldman]

Carroll,
I do not want to confuse the issue, but I have found a problem common to both the ST120 and ST124. It seems that the original pendulum leaders do not stand up very well and they get replaced. When this is done, the replacement leader has a wire that is thinner than the original. This makes the slot in the crutch very loose on the new wire. The pendulum leader will then kind of "rattle" in the crutch with each swing. This seems to rob the verge assembly of energy and stop the clock after a period of time. Sometimes the movemenet will run a few days, sometimes an hour.
To solve the problem, I have narrowed the slot in the crutch to fit the pendulum leader or have built a new pendulum leader with a thicker wire. The difference in thickness in the original wire and the replacements is not really that much (like .015") but it seems to be enough to cause poor service. With the movement running on a test stand, it is fairly easy to see the problem.
I have a 124 on a stand now that is a bit different than any I have ever seen. The spring "barrels" are riveted to the bottom plate rather than being attached with screws. In addition, the winding arbor hole in the time train barrel is off center. So, go figure. http://nawcc-mb.infopop.cc/groupee_common/emoticons/icon_wink.gif
Best of luck
Dick Feldman

[Len Lataille]

Apparently, Geo is not the only person that is confused. Carroll is having problems with a ST 120 movement. The 120 is a time and strike, only. The ST 124 movement, which others keep referring to, is a completely differnt movement. That movement (the 124) is a time, strike and chime.

Len
THE CLOCK CUCKOO

[Dick Feldman]

The ST120 and ST124 are two different movements but share some of the same quirks and problems. One is the two train version and one is the three. Both of these movements have similar construction. It is too bad there is confusion with this as both movements can be headaches for the repairman. http://nawcc-mb.infopop.cc/groupee_common/emoticons/icon_frown.gif

[Carroll Hardin]

Many thanks to all of you who have tried to help with my s.t.120 movement problem. This is very perplexing, as when I first got this clock in, I adjusted and oiled and everything worked fine. After sending it home, it began to run spasmodically from 2 to 4 days. I detected a coned mainspring on the time side, which seemed to hang up on the internal brads in the box. I installed a new spring and now it won't run as well. I am going to completely dis assemble and start over. Will advise if I am successful.
Thanks again.
Carroll

[Jeffrey R. Wood]

This whole family of ST movements has a reputation for being extremely tempermental even after being expertly cleaned, oiled and properly rebushed where necessary. The problem is that even the slightest amount of wear and rounding of the impulse faces of the verge will not allow the pendulum enough kick to keep the clock running any length of time. Probably 9 out of 10 clock repair people will do the verge more harm than good in trying to correct this problem. The impulse faces of the verge MUST be perfectly flat, at the right angle and highly polished in order for the clock to run any length of time. Probably no one is skilled enough to do this by hand. You must have an accurately made jig, and if the verge has been previously worked on, you might as well forget it.

Jeffrey R. Wood

[jacks61fd]

Carroll have you managed to get this movement running yet, if not I just recently was working on one and had a problem with erratic stopping and not much power getting to the pendulum--small swing -- a friend made a very strange suggestion - something I have never encounted or read about--he said that on these movements if the suspension sping is raised up high for timing so that the bottom block on the spring and the pendulum hook are near the fork of the adjustment piece it tends to rob power - he said lower the suspension spring which of course lowers the pendulum and would cause the clock to run slow but then raise the pendulum on its rod to bring it back in time keeping-- I don't know why but it worked the clock is running with a much better pendulum swing. JACK

[Jeffrey R. Wood]

The method described by Jack really does work! Several years ago I purchased for my own collection a gorgeous walnut-cased 120 in near-mint condition, but gummed-up. I thoroughly cleaned and oiled it, set the regulating device in the median position, but could not get it to run more than a few minutes. So I put it aside figuring someday I'd polish the pivots and verge and try again. The years went by, and then I saw Jack's posting above. Well, I got the clock out, still fully-wound, and lowered the pendulum all the way-- and the clock really came to life with a healthy pendulum swing! So I raised the pendulum a bit and found the clock losing 20 minutes a day. Thought maybe it would still keep time below the median setting, but no. It started stopping just as it was beginning to keep good time. What could I do, as the bob is non-adjustable? I knew if I cut the hook off and made a new one, the clock would run too fast. So I cut about 1/8" off the tip of the hook, and re-formed it. Didn't like the crutch engaging the rod so near where the suspension spring is attached, so was able to "stretch" it by altering the bends somewhat. Now the clock runs 8 days and keeps excellent time! Then I tried lowering the pendulum on 2 124's, which extended the running time slightly on one, and had no significant effect on the other, which has some slightly worn pivot holes.

But didn't all these clocks run OK when they were new? Of course they did. But just barely, so it didn't take much wear to make them quit. Here's my analysis of design flaws in the 120-124 movements, the first 2 of which are found in the 89's and certain others as well:

1. Pivots too soft

2. Oil sinks too deep

3. Suspension spring too springy

4. Pendulum bob too heavy

Jeffrey R. Wood