Mended Mainspring: Use or Replace

Discussion in 'Clock Repair' started by Bates, Jul 29, 2017.

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  1. Bates

    Bates Registered User

    Feb 6, 2013
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    Hi,

    I'm currently overhauling a Pickard & Punant 8 day T/S movement and have discovered that the strike ms has been mended in two places (see attached photos). Given that the strike was working before I disassembled the movement, would it be advisable to just inspect and clean the spring and reinstall it or get a new one assuming that the rest of the spring is in good shape? I've never run into this situation before.

    Thanks,

    Bates 311924.jpg 311925.jpg
     
  2. R&A

    R&A Registered User

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    All depends on if the spring for the strike will last longer than the the time spring. Plus you may want to get the spring to lay flat when laying on a table. The inside should not be sticking out like that. If the spring is in good shape and has no cracks and pitting. You'll have to inspect the spring.
     
  3. wow

    wow Registered User
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    Bates, I would not reuse that spring. As R&A says, it is coned from pulling it out with pliers, and those repairs are gonna break at some point. Buy a new one and do it right.
     
  4. Bates

    Bates Registered User

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    The question has been answered. As I was trying to measure the spring's length, after having pretty much decided to get a new one after reading r&a and wow's replies, the spring broke at the inner repair.

    Thanks for for your input

    Bates
     
  5. R. Croswell

    R. Croswell Registered User

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    You are lucky. It broke before you had it back in the clock!
     
  6. roughbarked

    roughbarked Registered User

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    Hear hear.
     
  7. kinsler33

    kinsler33 Registered User

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    Yep. I have an ancient Ingraham mantel clock that keeps coming back here with one weird problem after another (it originally came in with the movement distributed in several containers.) So finally it seemed okay, and I just wanted to make sure the countwheel strike was synchronized. Bong, bong, bong, spronnnnnng: the strike mainspring broke, not far from the center, and now the wretched thing is wedged into its case. I've been keeping a few Timesavers bargain American time-and-strike mainsprings on hand (#18790) for just such eventualities, but still.

    I had another Ingraham mainspring break recently, at the outermost coil, which I thought was unusual.

    M Kinsler
     
  8. Bruce Alexander

    Bruce Alexander Registered User
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    I think it's pretty amazing that someone would even try to salvage that broken spring in the first place. After the first break it was time for that steel to get melted down and turned into something else! :chuckling:
     
  9. shutterbug

    shutterbug Moderator
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    #9 shutterbug, Aug 2, 2017
    Last edited: Aug 2, 2017
    I've seen several springs that were dove tailed together after a break. It must have been standard procedure when springs were harder to get, or too expensive. Or perhaps it was a common work-around that did not require splitting the plates. At any rate, they seemed to do the job and lasted a long time.
    I would actually attempt the same repair if I were working with an old original brass spring (dove tail, not rivet).
     
  10. Jeremy Woodoff

    Jeremy Woodoff Registered User
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    How do you dove tail a mainspring?
     
  11. Bruce Alexander

    Bruce Alexander Registered User
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    I disagree SB.

    I've seen them too...or at least photos of them. We don't know how long ago any of those repairs were done or how many winding cycles they went through. Catalog reprints in Tran Duy Ly show that replacement/repair parts were made available to the public so I just can't buy that replacements weren't available. They may have cost more than the repairer or owner was willing to spend so by that definition they were too expensive. If a spring breaks like that once, I'm going to assume that the remaining coils are probably not much better. Sure, a chain is only as strong as it's weakest link but that doesn't mean that the surviving links are much stronger than the one which broke.

    As for a Brass Spring, that's a different situation with a relatively rare, historically significant part.

    No way am I going to cobble together a broken steel spring like this one regardless of whether we're talking rivets or a dovetail (which by definition would be a "weak link").

    Just my opinion.
     
  12. shutterbug

    shutterbug Moderator
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    #12 shutterbug, Aug 2, 2017
    Last edited: Aug 2, 2017
    Well, you said you disagree, T after T .... but I think you agree. I wouldn't do it either, with the exception of brass.

    Here's an old thread that includes a dove tailed mainspring. You can't see it well, but the dovetail has a triangle cut into the first part (broad side away from the break) and a corresponding "male" triangle cut into the other end, broad side toward the break. The two fit together and provide a pretty secure bond.
     
  13. Bruce Alexander

    Bruce Alexander Registered User
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    We usually agree more than we disagree, SB. I simply state that we don't know how long or how many cycles these kind of repairs have stood up to. I think the parts, certainly springs, have always been available. If not from the manufacturer, then from suppliers. Folks may be too frugal to spring for new spring, but I think that's more of a personal choice. So be it. I'm not judging. I would choose to replace the broken spring. If a clock came across my bench with a mended spring like this one, in my view it is not worth the risk to the rest of the movement, so it's gone.

    The one the OP brought up for question broke before he could get anyone to weigh in on whether or not to replace it.

    I remember parts of a thread on salvaging a brass mainspring with dove-tailing. My take away from it was that, for most, the risk of failure in the area of the dovetail was worth keeping the brass spring. I understand that. I may never lay my hands on such a rare bird. If I do, I'll probably be here asking for advice and help. :cool:

    Regards
     
  14. gocush

    gocush Registered User

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    Here's what happens when someone is too cheap to replace a broken mainspring.
    307071.jpg

    An without a barrel the clock likely would have been destroyed with pieces flying around.
    Get a new one and save yourself a huge headache. IMHO
     

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  15. shutterbug

    shutterbug Moderator
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    The damage shown in your picture gocush is the result of a spring breaking while under nearly full tension. The resultant multiple breaks are from the natural domino effect as the different parts of the spring are stressed beyond their strength as the spring explodes inside the barrel. I have seen such breaks often, and have never attributed them to a repairman re-using a broken spring or trying to repair one. However, if you were to make a point that a person might be too cheap to pay for regular maintenance that might prevent such a disaster from occurring, I would be in full agreement :)
     
  16. Bruce Alexander

    Bruce Alexander Registered User
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    I agree. The only thing we really know for sure is that sucker needs to be replaced now! ;)
    There appears to be some rust going on. That's usually an indication to replace a mainspring for me but some folks will just sand rust off if it's not too deep.
    Be very careful getting it out of the barrel and good luck determining the proper dimensions for the replacement. Let us know if you have any trouble. Members here can help you with that.
     
  17. kinsler33

    kinsler33 Registered User

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    I just encountered an anniversary clock with a shattered mainspring, and it also happened in a horrible wind-up phonograph in which the springs cost something like forty bucks each and I needed two.

    Repair parts can be a problem if you have a factory wishing to profit from them, as is the case nowadays with LeCoultre, maker of the Atmos clock.

    Now, I don't know about the practices of clock factories in past centuries, but early radio manufacturers had a rich history of disguising their replacement parts so they couldn't be purchased from anyone else. In fact, it seems that this is where resistor color codes originated. Until the EIA standardized the system, a resistor with a stripe sequence of brown-black-red could have been anything (now it means 1000 ohms, and I'm pleased that I remembered that.) It is possible that mainsprings may have been similarly burdened in some cases.

    There is also the ethos of the old fix-it shop at work here. Rural blacksmiths and their descendants who repaired locks, home appliances, clocks, bicycles, and everything else that a thrifty community might present took a great deal of pride in repairing rather than replacing existing parts. While it is true that many such repairs fill the NAWCC Hall of Shame, the context was that of a not-very-prosperous rural community, a fairly desperate customer, and a repair guy like me who wanted to be a hero.

    These guys were not museum curators, so they made things work as well as they could with minimal resources. (There are websites devoted to more recent examples of mechanical cleverness: do a Google search on the term "There I Fixed It." )

    Times are different, at least at present, but mainspring repair seems to be discussed in several old clock books.

    Mark Kinsler
     
  18. Bruce Alexander

    Bruce Alexander Registered User
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    Hello Mark. I don't want to take you out of context but it struck me that any business has to make a profit or it can't be in business very long. Do you mean folks who try to make obscene profits through price gouging? If so, I agree. I'm reminded of certain smug little owners in the Pharmaceutical Business now....

    Fortunately, mainsprings can be measured. Tran Duy Ly has catalog reprints which specify original spring dimensions (Seth Thomas for one), and helpful folks who keep/kept publicly accessible records of what they've found during their years in the trade. https://mb.nawcc.org/showwiki.php?title=Clock_Mainspring can be very helpful.

    With more experience, I'm less judgmental than I used to be. Without provenance or service history we often don't know the circumstances which lead up to the state of a clock on our bench. I still think that that the best repairs/maintenance are almost always invisible ones, but we can marvel at creativity and craftsmanship, even if it is misguided.
    I still do get upset by butchery though. Don't care how quick the kill nor sharp the knife. Yoda
     
  19. R. Croswell

    R. Croswell Registered User

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    For sure I would not attempt to 'repair' the OP's broken spring but I believe it is significant to note that the previous two repairs did not fail! It was the spring that fractured again so one would have to assume that the conditions that caused the first two fractures are still present and attempting to "mend it" again would amount to doing the same thing over and over and expecting a different result, and we know what that defines. It isn't the 'innovative repair' that's the problem. As for justifying the first repair attempt, since many of the clocks we are now seeing have survived two world wars and a great depression, and perhaps local and personal 'ups and downs', that may have been the only option except trashing the whole clock. Now 'repairing' the second fracture is less justifiable and a third attempt would be well, rather foolish. Like tying another knot in a rotten rope.

    RC
     
  20. kinsler33

    kinsler33 Registered User

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    Yes, I meant a non-larcenous profit. The problem with LeCoultre is that they're selling their Atmos replacement parts to (supposedly) one guy, who can presumably charge others whatever he wishes for them. If Timesavers and other catalogs are any indication the strategy hasn't worked so well, for they sell some Atmos parts, and so there are now a number of shops who do Atmos clocks, mine included.

    M Kinsler
     
  21. Bruce Alexander

    Bruce Alexander Registered User
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    RC Good analogy with the "rotten rope". That's the point I was trying to make with the "weakest link" but I like your analogy better. I must confess that I only focused on the OP's second photo and missed the fact that there was a repair in one of the outer coils. Maybe they were done at different times, perhaps they were done by the same person at the same time. Who knows? I try to just focus on results but it's fun to speculate on the history of an antique and try to put it into context.

    M Kinsler I think a problem of affordability may also be compounded by a shop wanting to make a profit on the parts too.

    Everyone has to eat.

    The cost of a spring should be relatively insignificant when compared to the cost of doing an overhaul. Regardless of the circumstances, I think it's an example of false economy to repair springs broken in this manner. I really like mechanical clocks so in my view efforts such as these are misguided, but clock owners don't necessarily have any attachment to these machines, especially if the darn thing don't work! Nothing to lose and everything to gain by getting it up and running as cheaply as possible, right?

    Atmos clocks are amazing btw.
     
  22. gocush

    gocush Registered User

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    In days gone by, there may have been a place for the Prairie Home Companion repair, but I would never send a clock out of my shop today with a "mended" spring, knowing that it could come back like the one in the photo I posted above. If a customer, or repairman, wants to save 15 bucks for that and spend $50+ on repair time, plus the knowledge that it WILL break again and blame me for the failure; I'd rather send them elsewhere up front.

    Shutter, the multiple breaks in that barrel spring are not the result of ONE event. That happened AFTER someone tried to "mend" it by riveting together broken pieces of a spring which should have been replaced in the first place. See photo after I got it out of the barrel. 312724.jpg

    I guess to each, his own. To me, this flies in the face of doing quality work. Risk/reward does not add up here, at least for me.
     

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  23. Bruce Alexander

    Bruce Alexander Registered User
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    #23 Bruce Alexander, Aug 6, 2017
    Last edited: Aug 6, 2017
    :chuckling:

    Maybe someone was teaching this method in the past?

    Time will separate good ideas from the bad.

    Leaving these in? Bad idea.

    I wouldn't even want to stretch them out for servicing.
     
  24. shutterbug

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    I agree with you in the big picture, gocush. But I do have to say that the repaired spring didn't break at the repair. It broke in a different place, and that's what caused the damage in your other photo. The argument that if it broke once, it will likely break again is reasonable, and it's good practice to replace a spring that has broken in the middle, regardless. I have often repaired a spring that broke at the outside hook though, and feel that this type of repair is both common and reliable. Whether to replace a spring that hasn't broke is a learned decision. With the poor quality of springs that are creeping into the supply houses now, it's always a crap shoot on whether the replacement will be better or worse than the original :)
     
  25. kologha

    kologha Registered User

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    If you lived in South Africa 20 years ago you would have had to revise your opinion. I have repaired springs in the past purely because they just were not available here. The internet has made life so much easier!
     
  26. Willie X

    Willie X Registered User

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    kolo,
    Internet or no internet, many springs simply aren't out there anymore, and this is an increasing problem for repairers.
    OP,
    That spring might be an old wrought iron spring. If it is, the replacement needs to be about 70% as thick as the old spring. Anything between 2/3 and
    3/4 the thickness of the older wrough springs usually works well. Wrought iron springs are very rough and usually about .022" to .024" thick.
    I don't know of a sure way to identify a wrought iron spring except they are brittle, thicker than usuall, and tend to stay rather small when free. Most come from the pre 1880s era. Once you see a few, they are easy to identify by sight alone.
    Willie X
     
  27. Bruce Alexander

    Bruce Alexander Registered User
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    #27 Bruce Alexander, Aug 7, 2017
    Last edited: Aug 7, 2017
    The quote you are responding to is mine so I'll respond to your statement too. I don't and didn't live in South African so perhaps you're right. I don't and never have lived in Europe either, but I've ordered mainsprings from European and Canadian Suppliers for Junghans Movements before. I definitely agree that the Internet has made things faster, but hard copy catalogs has been with us for a very long time and are still used today. For example, I find it much easier to locate a spring in Timesavers' catalog than I do on their website unless I know the part number. Maybe I'm just getting old and prefer the printed page to a keyboard and screen. I can not say with any certainty that I would not have repaired a spring 20 years ago. Twenty years ago I was not involved in clock repair. I can say with certainty that I will not do it today. If I can not find a suitable replacement spring, I'll have to look into having one fabricated. Evidently, they are not that expensive and they are certainly less expensive than re-doing an overhaul with catastrophic damage...one which will still require the replacement of a broken spring.

    Regards

    P.S. As per S.B.'s comments, I have "repaired" torn out hole-ends or have removed the broken outer end of a mainspring before. I have acquired a punch for placing new holes in the ends of springs which can still be used with some repair so I don't believe I'm being dogmatic here. I'm just trying to do what I think will give the best results over time. That usually involves the benefit of hindsight be it my own, or experiences shared by others.
     
  28. R. Croswell

    R. Croswell Registered User

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    Usually one can usually safely repair an outer end torn out end hole which likely began as a small stress crack where the hole was originally punched. One might also consider "repair" when the fracture occurred at the interface between the annealed end and the tempered 'working body' of the spring. Under these circumstances the cause of the fracture is rather obvious. When the fracture occurs someplace in the tempered 'working body' of the spring for no obvious reason (as in the example of this thread) one has to suspect that the defect that caused the original failure is likely distributed through out the spring creating a high probability that another failure will happen if that spring continues to be used. One cannot usually repair broken inner coils without significantly shortening and/or overstressing the remaining spring. That being said, My first clock had a main spring broken at the inner coil and I did clip off the broken part and form a new inner coil and the clock ran for 30 years before I replaced that spring, not because it broke again but because the spring was a little shorter and caused the strike to run down before the time (I didn't know of any source for new springs back in 1967.) With the possible exception of a torn out outer end hole, I prefer to replace broken springs as the first choice.

    RC
     
  29. roughbarked

    roughbarked Registered User

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    I've attempted a lot of things and been successful most of the time. Sometimes the assessment is wrong. The mainspring has already been repaired and was otherwise unnoticeable or one of many possibilities. Sometimes the repair goes wrong. It is unwise for example to make any filing marks transverse to the grain. They must always be along it. I've told the customer. If you want a new mainspring for your two hundred year old clock then you will need to buy 100,000 units. Would you prefer to wind it up every seven days, or eight?
     
  30. Bruce Alexander

    Bruce Alexander Registered User
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    Thus far I have always been able to find a suitable replacement spring when I thought it was called for (a broken spring riveted back together for example).

    However:
    This option was discussed in a recent thread. Harold Bain pointed it out and shared the fact that this resource has been listed on the MB for many years.

    • Timewise (formerly Tani Engineering)
      i330-947-0047 email: twclock08@att.net
      Larry Wise
      Custom Made Mainsprings
    https://mb.nawcc.org/showthread.php?41993-Clock-Suppliers-General-Supply-Tools-Repair-Service-Etc

    I don't think they require a customer to order huge runs, although I bet they would be all to happy to oblige.

    I will concede the point that information is much easier to come by in the Information Age.
     
  31. roughbarked

    roughbarked Registered User

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    I will also concede that I'm talking about thirty years ago in Australia. Where I had to call an overseas manufacturer and he did say, "I can make it but I need to do a run of 100,000".
     
  32. Bruce Alexander

    Bruce Alexander Registered User
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    Fair enough Mate. I am not here to judge the work of anyone. I'm here to improve my skills, share experiences if it will help others and get a good chuckle from time to time. This is not Facebook or Twitter (Thank goodness) but there is a social media aspect to it. How else can experiences and information be shared in almost real time as well as in future archive searches?

    It would gnaw at my conscience, however, if I tried to "make do" with a movement/spring in the condition which was the purpose of this thread in the first place. We do live in the Information Age, but one usually still has to search for what one is looking for...although the geniuses behind "targeted" ads and their lapdogs in the U.S. Congress would beg to differ. Even so, they look at your browsing history to "help" you find "stuff" ...but I digress into restricted areas here so...:whistle: One doesn't have to go to the Library to make an informed decision anymore. Wouldn't hurt though. ;)
     
  33. roughbarked

    roughbarked Registered User

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    Some mainsprings can be repaired. Most cannot. A new mainspring is always to be preferred unless there is no other apparent course of acrion. I'd never re-use an already repaired mainspring.
     
  34. bangster

    bangster Moderator
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    I'm imagining a garage mechanic who never heard of Timesavers.
     

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