Removing a mainspring?

Sammyt97

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Aug 18, 2006
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Hi everyone,

I need a little bit of help. I just purchased a Daniel Pratt and Son mantle clock with a Ingraham movement. When I opened up the back of the clock I found the mainspring to be unwound. It didn't not respond to my winding and when I took the movement off, I could see that the mainspring is either broken or not catching. I would like to remove the mainspring, do I have to take apart the entire movement? It's a loop end mainspring. If I do have to take it apart, I won't be able to wind it, but the hourly chime is wound pretty tightly. Will I have to clamp that? Can someone tell me how to do that?
Thanks,
Chris
 

eskmill

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Because you have the movement out of the case and are able to examine it closely, you should be able to determine why the time train mainspring can't be wound.

While observing the coils of the mainspring, insert the winding key and twist. If you see the inner coils moving with the winding arbor but the outer layers of coil don't follow, then the spring is broken.

If, on the other hand, you can see the arbor turning with the key, but the spring doesn't wrap around the arbor, then possibly the hole in the innermost coil is broken off leaving nothing but an open slot to catch on the winding arbor hook.

There is a possibility that the innermost coil has become "un-hooked" from the winding arbor.

If that's the case, then try putting some lateral pressure on the spring while turning the key. You may be able, using an ice cream or popsickle stick, to force the inner coil to catch on the arbor hook, then wind it up tight to "reform" the inner coil so that it will not become unhooked from the arbor again.

Most clock movements using loop end mainsprings must be dismantled to replace the mainsprings.

BEFORE disassembling the clock, tie the spring or springs tightly with bailing wire so that the spring has no force, else when the movement plates are separated, parts will fly all over your workspace and damage is likely.
 
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Steven Thornberry

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Sammy:

I'll throw in a couple of words until the real experts come along. Yes, you will have to take the movement apart to remove the broken spring. Yes, you will need to clamp the strike spring. The movement probably needs a cleaning, bushing, overhaul, oiling etc. before using it again.

You might also want to find a proper movement for the clock eventually. The Ingraham is wrong for a Daniel Pratt case.
 

Scottie-TX

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I may be wrong but to be on the safe side, in addition to tieing off the partially or fully wound spring, I would "let it down" into the tie as there may be further potential in the spring even tho tied.
Not such a risk on the unwound side as it is pretty well spent at this point. Tieing it off should be sufficient.
 

shutterbug

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Well, yes you can replace the spring without taking it apart. It may not be the wisest thing to do, but it can be done :) You'd have to remove the broken spring (if it is broken) and cut off the loop. You can order a new spring from Timesavers (#18790). After you get it, you have to release the tension and clean it, then oil it with mainspring oil or Slick 50. If you are brave, you can release the tension this way:
Hold the spring tightly in your gloved dominant hand. A good grip now, then cut the wire with some wire cutters. Slowly open you hand and the spring will unwind. It sounds more scary than it is :) Now you'll have to drill out the rivet in the loop and find a way to get the inner coils open enough to get them around the arbor (be sure you're going the right way. You won't want to do it twice :)). Now you can wind it a bit and position the loop around the post. Secure it with a rivet, or be inventive. Not a huge amount of pressure there. Wind it up, and you're ready to go.
Note: This won't fix any other existing problems, so there's no guarantee it will run. It would be best to have it serviced by a pro.
 

harold bain

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Hi everyone,

I need a little bit of help. I just purchased a Daniel Pratt and Son mantle clock with a Ingraham movement. When I opened up the back of the clock I found the mainspring to be unwound. It didn't not respond to my winding and when I took the movement off, I could see that the mainspring is either broken or not catching. I would like to remove the mainspring, do I have to take apart the entire movement? It's a loop end mainspring. If I do have to take it apart, I won't be able to wind it, but the hourly chime is wound pretty tightly. Will I have to clamp that? Can someone tell me how to do that?
Thanks,
Chris
Chris, if you intend to get this deep into clock repair, I would suggest you start off with a few good basic clock repair books. Taking a movement apart without proper preparation is sure to end in disaster for the movement. Is this an eight day or 30 hour clock?
 

Sammyt97

Registered User
Aug 18, 2006
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Massachusetts
Chris, if you intend to get this deep into clock repair, I would suggest you start off with a few good basic clock repair books. Taking a movement apart without proper preparation is sure to end in disaster for the movement. Is this an eight day or 30 hour clock?
Hi,
Thanks for your reply. It is an eight day clock. I do have a couple of books for basic repair, but unless there are really good visuals, the reading piece doesn't help me a lot. If you have any recommendations about a good book, I'd love to know what will help. Thanks so much.
Chris
 

harold bain

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Chris, I would recommend Philip Balcomb's two books, The Clock Repair Primer, and The Clock Repair First Reader. They are both very basic, with discussion on what tools you need, and diagrams of clock parts. What books do you have?
 

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