Jump to content

400 day clock


Salman

Recommended Posts

I'm a newbie learning to fix a 400 day clock that I just bought from a friend. I have a problem with a broken suspension spring. Can someone help me with thickness and length of suspension springs for kern & sohne clocks? I can't fix, because I don't have the manual I need This is my 400 day clock body shape, seen from behind Thank you in advance

IMG-20220605-WA0011.jpg

IMG-20220605-WA0008.jpg

Link to comment
Share on other sites

Hi  What you have got is a kern and sohne clock .  Can you post apicture of the backplate face on as I am trying to locate the plate in the 400 day guide.and the position of the pallet bearing and escapement inspection holes  coupled with the logo position amd the winding s quare dont seem to fit any images. also what is the measure ment of the back plate.    It could be units 12A   12B   12c   or  unit 118       Kern standard uses .0036 so to be sure a square on picture would help a great deal.

Link to comment
Share on other sites

I'm afraid this is the best picture I can give at this point. But I can't wait to fix it soon. Because this is a new experience for me.

Maybe next time, I'll post a better picture, of course after confirming the size of the backplate

Besides that, I also can't find a picture of a clock that is exactly the same as it, on the internet. To ensure its originality so that I can restore it to how it was

Link to comment
Share on other sites

Don't worry too much about finding the exact match in the book. I checked the 10th edition and I can't find an exact match. I fixed my first anniversary clock before I got the book. I think the images of the specific suspension wires have become a little blurry after so many revisions and reprints of the book.

You can measure the old spring with a micrometer to determine the thickness. The length can be determined by attaching the pendulum and checking that it is able to rotate freely without rubbing against anything. Then getting the correct position of the crutch might be a little tricky. It will take a bit of trial and error to get it right. But even if you follow the pictures in the book, some tweaking of the position of the crutch is necessary to get good amplitude.

I know @oldhippy will be probably be frowning when he reads this.

  • Like 2
Link to comment
Share on other sites

1 hour ago, HectorLooi said:

Don't worry too much about finding the exact match in the book. I checked the 10th edition and I can't find an exact match. I fixed my first anniversary clock before I got the book. I think the images of the specific suspension wires have become a little blurry after so many revisions and reprints of the book.

You can measure the old spring with a micrometer to determine the thickness. The length can be determined by attaching the pendulum and checking that it is able to rotate freely without rubbing against anything. Then getting the correct position of the crutch might be a little tricky. It will take a bit of trial and error to get it right. But even if you follow the pictures in the book, some tweaking of the position of the crutch is necessary to get good amplitude.

I know @oldhippy will be probably be frowning when he reads this.

Actually I really want to do that. By doing a little experiment on the clock. It's just that when I think about replacing the suspension spring, a lot of questions come to my mind.

How long is the spring required?

How flexible is the spring?

Spring material that does not break easily when moved to rotate the pendulum?

And some adjustments to the position of the crutches as you stated above😔

Link to comment
Share on other sites

2 hours ago, Salman said:

Actually I really want to do that. By doing a little experiment on the clock. It's just that when I think about replacing the suspension spring, a lot of questions come to my mind.

How long is the spring required?

How flexible is the spring?

Spring material that does not break easily when moved to rotate the pendulum?

And some adjustments to the position of the crutches as you stated above😔

The new spring will longer than required, you will have to cut it to length. Although the spring is elastic, it does get deformed and kinked quite easily, especially when the pendulum is relatively heavy. Even the weight of the upper suspension block and the crutch alone is enough to deform the spring. The spring has to be handled with utmost care.

Actually, from your photos, I can see that the old spring still has the crutch attached. You can mark the position of the crutch and use that as the reference for the position.

Good luck and don't be afraid to ask if you have any problems.

Link to comment
Share on other sites

I’ve just finished one here, be very careful of the torsion spring ok, ( suspension spring )they are very apt to being bent or twisted.
Once bent or twisted they are useless and you’ll need to order another. If you order a horolover one then they do come with blocks and forks attached at the correct height. 
If you intend to work on these then the horolover book is essential, so well worth buying it now as it has a Q&A section and so much info in it.

1190642D-4E85-46DB-9E4F-24098AFE7F35.jpeg

7D87C831-5979-4482-B7EF-A885E3A0B385.jpeg

86B9CD6C-973A-43B9-8A81-38FAF0B2414D.jpeg

  • Like 1
Link to comment
Share on other sites

2 minutes ago, transporter said:

If you intend to work on these then the horolover book is essential, so well worth buying it now as it has a Q&A section and so much info in it.

 correct. for the price the information is brilliant. well worth the money as is the adjuster tool for the block as it allows fine adjustment of the upper block.

beat adjuster tool.jpg

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • that band is old as stated, there is a kit that pops up from time to time on selling sites for the repair of these type bands, some of this type are adjustable on a few links, one adjustable type allows you to align the round opening in the expansion slit [like yours] with the rivet to separate, but if yours won't come out then the rivet head is too big and will have to be done with some rivet removal and replacement, I suppose if you could make/optain the correct rivets that one could alter the said band, the tops/caps do lift off after raising the tabs....  
    • This is a watch from a friend who sent it to a neighborhood watchmaker for a battery change. It came back with the watch stem in a ziplock bag and the dial skewed 20°. The watchmaker told him that the stem was faulty and the watch cannot be repaired. I opened up the watch and found that one dial foot was broken off and still stuck in the movement, while the other was bent until it was flat against the dial. The stem could be inserted but it couldn't be pulled out to quickset and time adjusting positions. I did a full disassemble, cleaned and oiled the movement. But when it put in the battery, the second hand runs super fast. Like it gains 30 mins every hour. Any advice on fixing this problem? TIA.
    • I determined that the balance staff is rotating, not the roller table, so my second attempt at riveting was unsuccessful. I have ordered a new balance staff and will take measurements when it arrives. The balance staff i originally ordered (and now reordered) was specified as: Replacement balance staff: (A. Schild Caliber 984 1002 1021 1124 Original Balance Staff Part 723) so it should be correct. Measurements: (see pic below for terminology) xxxyy is a place holder until the new balance staff arrives. Lower pivot: Old - .08 mm New - xxxyy Lower pivot to balance seat: Old - 1.53 mm New - xxxyy Roller shoulder: Old - .42 mm New - xxxyy Hub: Old - xxxyy New - xxxyy Balance shoulder: Old - .86 mm New - xxxyy Collet shoulder: Old - .56 mm New - xxxyy Upper pivot: Old - broken New - xxxyy
    • Hello and welcome from Leeds.  We're here to help. 
    • I was just about to adk that, probably they have unnecessary waiting lists to make their watches appear more exclusive than they actually are.
×
×
  • Create New...