Turning a balance staff--check my numbers

[Neverenoughwatches]

22 hours ago, nickelsilver said:

I haven't seen a balance complete that was intended to have the overcoil formed by the watchmaker, but it could exist. One thing to check- pretty much all Breguet springs have a collet with the hole for the spring significantly lower than a normal collet (normal would be hole right in the middle of the collet height). If your spring is in the middle, it was to be a flat spring.

I noticed that on the collet of a movado i have. At first i though the spring had been damaged. It runs amazingly well for what was a battered old watch.

14 hours ago, LittleWatchShop said:

Here is what I purchased.  I have myself to blame, as clearly there is no overcoil in the pictures

I have my eye on a couple of donors as a backup.  One is in the UK and the seller will not ship to US, but another has already made the trip.  As earlier stated, I will attempt the over coil...but I need a backup plan.

I have been in contact with the seller.  This is my mistake due to my inexperience.  The seller offered to refund the sale, but I did not accept it since I clearly could see what I was buying.  Lesson learned.

The 571 can come with and w/o the over coil as seen in this document image.

New question.  Is the only difference between the planar and over coil implementations the regulator pin length?

Although the package shows a breguet.  Whatever

 

Changed at some point in its life ? NOS or not. Robbed of it original hs replaced with a flat spring ?

23 hours ago, LittleWatchShop said:

I just don’t know. What you say is plausible, however.

regardless, I am going to have to learn to bens a Breguet.

I watched a good video of how to bend a brequet while i was trying to work out what i had. I'll  see if i can find it and post a link. The music did my head in a bit though. Fortunately you can turn it down as there was no commentary. 

23 hours ago, LittleWatchShop said:

I just don’t know. What you say is plausible, however.

regardless, I am going to have to learn to bens a Breguet.

https://m.youtube.com/watch?v=ID2Ndl6igwM&t=101s

35 minutes ago, Neverenoughwatches said:

I noticed that on the collet of a movado i have. At first i though the spring had been damaged. It runs amazingly well for what was a battered old watch.

Changed at some point in its life ? NOS or not. Robbed of it original hs replaced with a flat spring ?

I watched a good video of how to bend a brequet while i was trying to work out what i had. I'll  see if i can find it and post a link. The music did my head in a bit though. Fortunately you can turn it down as there was no commentary. 

https://m.youtube.com/watch?v=ID2Ndl6igwM&t=101s

The forming tweezers are ridiculously expensive. An old pair of standard are going to require some shaping and dressing.

[Klassiker]

Hats off to you for attempting to form the overcoil yourself. You've nothing to lose If your conscience compels you to not return the incorrect part. Trying to find the correct part at the same time is obviously a good strategy. Apart from donors, I would keep up the search for the NOS part. Watchguy UK for example has a useful list of available parts and links to potential sellers. Good luck!

[LittleWatchShop]

This is iteration number six or seven...it is hard to keep count.  Methodology for this turn was aided by a number of phone calls with a forum member...coaching me...

I made a carbide file to do the finish work on the roller side.  It polishes extremely well.

Full disclosure...I started with a large pocket watch staff because I have had some issues with my other starting material.  However, I made every cut except for the hub.

I am posting this now while I am happy before disaster strikes.  Today, I will install the balance, check the fitting in the watch...then install the rest.

No matter what happens, I can say for sure that my skills (minimal as they are) are improving.

I think the pivot on the left is a little short, but hoping it will work fine.

 

[Nucejoe]

Congrat Littlewatchshop.  Your steady improvement eversince you started, is examplary.  

 

 

[LittleWatchShop]

Update. The roller and hairspring fit fine except when I installed the balance, the roller jewel rides over the pallet horns, so the roller is sitting too high. I am going to have to nudge it down a bit.

I use Rex Roller Remover whenever messing with rollers, so I think I will set it up and just tap the balance down a hair.

My respect for you guys who do this stuff daily has gone up an order of magnitude!

[nickelsilver]

Well it looks like an excellent go there! As you've noticed, most sources on staff dimensions give a lot but not all the info. If you had had the length from bottom pivot to hub you would have been fine- and the hub length dimension can vary quite a lot.

 

If anything, I think the pivot on the left (top pivot) looks just right, the lower one is a bit long. Great work though.

[LittleWatchShop]

On 8/21/2022 at 10:46 AM, nickelsilver said:

If anything, I think the pivot on the left (top pivot) looks just right, the lower one is a bit long.

Confirmed.  It was too long.  I cut it back 10 to 20 microns for a good fit.

Here is a complete update.

I assembled the balance with the roller only.  Removed the pallet fork from the watch.  Then assembled the balance in the movement with balance cock in place and tightened.  Using a puffer, I could make the balance spin very fast and seemed to have a nice gradual spin down.  All looked well.

I reinstalled the pallet fork, and then I added the hairspring and assembled the full balance.  Installed in the watch, it ran...but with low amplitude.  I checked the HS to see that it was not rubbing.  I adjusted the beat (as observed on my oscilloscope).  The balance was not rubbing either.  Just low amplitude.

A little exasperated, so I decided to try something that I had avoided.  Some time back, I had purchased a NOS balance complete but it was not the breguet version, so it has set to the side.  I had never attempted to try this with the breguet HS because the collet had a larger diameter than the staff.  While chatting with my phone buddy, he told me to collapse the collet using a concave punch (taking not of doing this on the end of the collet.  So, I did this with success.  This is a great idea BTW and is now in my bag of tricks.

With the NOS balance and original HS, the watch performed the same.  This, oddly, was comforting because it seemed to imply that my staff was not the problem.

I have observed this thing under high power microscope and I cannot find any HS rubbing on the balance.  The HS appears planar in in a plane parallel to the balance wheel plane.  I do not see the balance rubbing against anything either.

I don't have a good feel for end shake and side shake, but I did tested it.  Seems a little much but I don't know.  The behavior of the watch is pretty much the same regardless of position.

One other thing I did...I landed a Cyma 573 on ebay (mine is a 571) and I took the MS barrel (with MS) and put it in the 571 in case the MS was just week.  This did not seem to make a difference.  I also disassembled the train wheels and looked for issues...nothing found.

Here is a slo mo just for grins.  Not enough magnification to tell anything...but this forum loves pictures.

Edited August 24, 2022 by LittleWatchShop

[Nucejoe]

Are you sure the hairprings match balances?  

Escapement might need adujutment.

[LittleWatchShop]

3 hours ago, Nucejoe said:

Are you sure the hairprings match balances?  

Escapement might need adujutment.

Lol...this journey started in April. I checked my ebay purchases today to address this very question. I think it is the HS for this watch. I love this path I am on in spite of the pain!

[LittleWatchShop]

Running on the bench...keeping good time.

BTW, it is sitting on a movement holder I printed specifically for this watch.

[LittleWatchShop]

This watch continues to prove that I am a rank amateur.

It has been acting up, so I dove back in to figure this out.  Lots of details I will not go into, suffice it to say, (as noted above) I made a new staff, and retrofit a hairspring and roller table.

It was going crazy slow and I started investigating the pallet fork horns perhaps hitting the roller table which led me to the pallet fork itself and the pallet fork plate. 

I noticed a lot of side shake on the pivot, so I measured the hole and compared it with a donor watch and found about 40um difference I think (measured it but didnt write it down).

I show the two plates here.  Wondering if I should close it a bit by staking.

This picture really does not illustrate the difference but everybody loves pictures.

Notice the different color of the plates.  I think someone filed down the one on the left exposing bare brass.