Kundo - anniversary clock; suspension spring

[Gabriel025]

Hello dear friends,

I just bought old Kundo watch... but it is super fast. I need to change suspension spring. Does somebody knows which dimensions I need? Watch is tall almost 30cm (11.8"). 

Dimensions of the spring mounted on the watch are - 126mm (4.96") x 14mm (0.055") x 0,08mm (0.0032").  Since the spring is bent, I'm not sure if these are the correct dimensions. It was measured with a ruler. On the Internet I find several different dimensions of springs for Kundo watches. Can you please help me and say which of these springs would be suitable for my watch? Pictures are from German watchparts seller. He said that they are original for Kundo anniversary clocks. They have marks 1, 3A, 3B, and 3C. I'm planning to buy just a longer spring and try to make the whole thing by myself, but I need correct measures.

Is the fork on the existing spring properly mounted? Isn't she facing the wrong way - upside down?

Thank you very much!

[Gabriel025]

I just realized that my question is in wrong section... Can I ask the moderator to transfer it to right section? I'm searching option to delete it or transfer, but I can't find it.

Sorry.

BR

[tomh207]

Moved to all things clocks as requested 

 

Tom

[clockboy]

The suspension spring is wrong it should be dead straight with no twists or turns.. The strength of the spring is critical to strong or too weak and you will run out of adjustment. If can supply with the measurements of the movements back plate I can refer to my 

“Horolovar 400 day clock repair guide” book to give the exact spring you need..

[nevenbekriev]

Hi Gabriel,

First of all, You need to undrestand if the existing spring is correct or not. To do it, You will need to untwist it. In such twisted condition, the pendulim will oscillate much faster. Untwisting is possible, but it will be hard to bring the shape back to ideal. No mater, the pendulum will oscillate normally as if the spring is not twisted. You need to turn the pendulum in untwisting direction several turns thus twisting the spring in the other direction, then check what has hapenned and if more turning the pendulum is needed to improve the spring.  As the spring will not untwist evenly, concentrate on it's upper part to untwist correctly. When it is done, grasp with tweezers under the rectified part and continue till all the lenght is done.

Then You need to understand what is the needed period of the pendulum oscillations. I have seen 20, 15, 12 and 10 sec. Observe the minute hand while moving the fork left-right manually, see how many moves atre needed for the hand to shift 5 or 10 min ahead, then divide this to the moves counted. After knowing the period needed, You can use timer to measure the real period when the clock is working and thus You will know fast if the period can be regulated to the needed value or not, and if the spring needs to be replaced. Thinning the spring is possible to slow the clock down instead of replacing it.

 

[clockboy]

See pics

 

[oldhippy]

Looks like you all have beaten me to this one. I'll just sit this one out. 

[watchweasol]

Me too , plenty of good men on the case.

[Gabriel025]

On 5/23/2024 at 11:02 AM, nevenbekriev said:

Hi Gabriel,

First of all, You need to undrestand if the existing spring is correct or not. To do it, You will need to untwist it. In such twisted condition, the pendulim will oscillate much faster. Untwisting is possible, but it will be hard to bring the shape back to ideal. No mater, the pendulum will oscillate normally as if the spring is not twisted. You need to turn the pendulum in untwisting direction several turns thus twisting the spring in the other direction, then check what has hapenned and if more turning the pendulum is needed to improve the spring.  As the spring will not untwist evenly, concentrate on it's upper part to untwist correctly. When it is done, grasp with tweezers under the rectified part and continue till all the lenght is done.

Then You need to understand what is the needed period of the pendulum oscillations. I have seen 20, 15, 12 and 10 sec. Observe the minute hand while moving the fork left-right manually, see how many moves atre needed for the hand to shift 5 or 10 min ahead, then divide this to the moves counted. After knowing the period needed, You can use timer to measure the real period when the clock is working and thus You will know fast if the period can be regulated to the needed value or not, and if the spring needs to be replaced. Thinning the spring is possible to slow the clock down instead of replacing it.

Hi! Thank you! That's great advice! I didn't know that this is possible. I will try it today after work and see if everything will be OK. 

[Gabriel025]

On 5/23/2024 at 9:38 AM, clockboy said:

The suspension spring is wrong it should be dead straight with no twists or turns.. The strength of the spring is critical to strong or too weak and you will run out of adjustment. If can supply with the measurements of the movements back plate I can refer to my 

“Horolovar 400 day clock repair guide” book to give the exact spring you need..

Thank you for help. From the pictures that you have posted, it seems that Plate 1407B have the same holes... Brand logo is on the different place... But holes seems to be in the right places. So, needed spring are 3A, 3B and 3C. From german seller, those models are the same lenght (126mm) but different fork height (14, 14.6, 14.8). Which one would be better? Iz such a small dimension important?   

[Dell]

On 5/24/2024 at 10:44 AM, Gabriel025 said:

Thank you for help. From the pictures that you have posted, it seems that Plate 1407B have the same holes... Brand logo is on the different place... But holes seems to be in the right places. So, needed spring are 3A, 3B and 3C. From german seller, those models are the same lenght (126mm) but different fork height (14, 14.6, 14.8). Which one would be better? Iz such a small dimension important?   

I restore torsion clocks and quite a few of the early ones there is nothing in the book so I lower the fork until it flutters ( drops more than one tooth at a time ) then raise the fork by 1mm, the book is only a starting position sometimes it’s ok other times not , every clock seems to be different.

everything is important with regards to torsion clocks .

Dell

[Gabriel025]

Guys, thanks for your help!

According to the advice of a colleague @nevenbekriev, I managed to straighten the spring. Surprisingly, it turned out completely flat. Like new. And the watch after that, for the first time since it was with me, started running late. That's great news!!! The rotation of the weights is about 190/200 degrees. In the past 12 hours, it was 4 minutes late. I still have enough room to speed it up. Looks like everything will be OK. 

Thank you very much for your help!