Hampden 16S Grade 110 'H' flag, circa 1898

[MechanicMike]

Hi all

I'm trying to repair this one for an old Viet Nam marine buddy, who said it hasn't run since the day his grampa gave it to him just before he deployed. What I found was that the upper pivot of the balance staff was gone along with the balance cock upper hole jewel was cracked  and chipped. I was able to secure a NOS balance, staff and hairspring assembled, and lucky enough that all the jewels and fits were good. I added a new white alloy mainspring for the heck of it, cleaned and lubed everything. Assembled it and put some power to the mainspring to check it all over to find what I thought was excessive endplay. I took the balance back down and under the microscope to find it looks like the staff upper pivot(or the staff OAL) isn't long enough to fit, or reach into the upper jewel when assembled. Is that possible? is the hairspring collet not staked to the shoulder? (I haven't gotten that far). 

1) should I mic the staff overall length and try and find a longer one?

2) I see there are stake marks between the balance cock and base plate seemingly to raise it up or for binding issues. should I blend those down flush?

3) should I attempt to find a different balance/bridge/hairspring assy. and replace the whole thing?

it wants to run that's for sure and does intermittently, which, after all the work, is encouraging to me. I'm soooo close. Can I fix this?

much obliged-

Mike

 

 

[jdrichard]

10 minutes ago, MechanicMike said:

Hi all

I'm trying to repair this one for an old Viet Nam marine buddy, who said it hasn't run since the day his grampa gave it to him just before he deployed. What I found was that the upper pivot of the balance staff was gone along with the balance cock upper hole jewel was cracked  and chipped. I was able to secure a NOS balance, staff and hairspring assembled, and lucky enough that all the jewels and fits were good. I added a new white alloy mainspring for the heck of it, cleaned and lubed everything. Assembled it and put some power to the mainspring to check it all over to find what I thought was excessive endplay. I took the balance back down and under the microscope to find it looks like the staff upper pivot(or the staff OAL) isn't long enough to fit, or reach into the upper jewel when assembled. Is that possible? is the hairspring collet not staked to the shoulder? (I haven't gotten that far). 

1) should I mic the staff overall length and try and find a longer one?

2) I see there are stake marks between the balance cock and base plate seemingly to raise it up or for binding issues. should I blend those down flush?

3) should I attempt to find a different balance/bridge/hairspring assy. and replace the whole thing?

it wants to run that's for sure and does intermittently, which, after all the work, is encouraging to me. I'm soooo close. Can I fix this?

much obliged-

Mike

 

 

I would cut another balance that fits. Buying one is a gamble as it may never fit.

[MechanicMike]

2 minutes ago, jdrichard said:

I would cut another balance that fits. Buying one is a gamble as it may never fit.

it's crossed my mind. I've been told that Hampdens are all over the board. Here I was worried that the pivots and jewel diameters wouldn't get along. I didn't anticipate OAL... 

[jdrichard]

10 hours ago, MechanicMike said:

it's crossed my mind. I've been told that Hampdens are all over the board. Here I was worried that the pivots and jewel diameters wouldn't get along. I didn't anticipate OAL... 

make your own and you can adjust the heck out of it until it’s perfect.

[MechanicMike]

5 hours ago, jdrichard said:

make your own and you can adjust the heck out of it until it’s perfect.

What I failed to mention, is that I have no ways to cut a new staff. I have no watchmaker lathe. I wish I did. 

[Nucejoe]

16 hours ago, MechanicMike said:

I see there are stake marks between the balance cock and base plate seemingly to raise it up or for binding issues. should I blend those down flush?

Thats what I do, if you assess removing the bumps would let the cock down enough for pivot to fully enter jewel hole, I,d give it a try. its easy, wont cost anything and levels the cock with gears bridge.

[JohnR725]

 

17 hours ago, MechanicMike said:

should I attempt to find a different balance/bridge/hairspring assy. and replace the whole thing?

did you notice when you are working on the watch that their serial numbers on all of the plates? There is even usually a serial number on the balance wheel. This is because American pocket watches initially even though there's a parts book even though interchangeability was supposed to exist the parts are usually hand fit. A lot of it depends on which company did the manufacturing and when they were manufactured. So it's usually a bad idea to start swapping parts between different movements.

18 hours ago, MechanicMike said:

should I mic the staff overall length and try and find a longer one

a important rule to remember when replacing balance staffs is to always measure the old one versus the new one. This way you avoid unpleasant surprises. A lot of times with American pocket watches the modern replacement staffs are deliberately made over size. This is because it's easier to reduce things to fit than it is to add on to your staff. So it's very important to measure before putting it in.

then a watchmaker lathe unfortunately on American pocket watches isn't an absolute must but just about. Even if you got the right staff you also find that the watch companies made staffs with the same part number with different pivots sizes. So you might have to reduce a pivots size or reduce the length sometimes they were made longer than ever supposed to be so you could fit them.

 

[MechanicMike]

6 hours ago, Nucejoe said:

Thats what I do, if you assess removing the bumps would let the cock down enough for pivot to fully enter jewel hole, I,d give it a try. its easy, wont cost anything and levels the cock with gears bridge.

you're right. I planned on it. Will it remove enough to lower the cock enough to engage pivot? time will tell..I just haven't got to it yet. I'll let you know.

[MechanicMike]

5 hours ago, JohnR725 said:

did you notice when you are working on the watch that their serial numbers on all of the plates? There is even usually a serial number on the balance wheel. This is because American pocket watches initially even though there's a parts book even though interchangeability was supposed to exist the parts are usually hand fit.

I sure did and only a couple matched. there were plenty of service marks so that tells me parts have been exchanged in this thing already long before I got to it. 

 

5 hours ago, JohnR725 said:

a important rule to remember when replacing balance staffs is to always measure the old one versus the new one.

correct. when I opened it up the first things I found was that the upper pivot was destroyed down past the cone(it was gone and not inside the movement), and the upper hole jewel was cracked in half under the cap jewel and chipped badly. probably dropped. so there was nothing to measure. i was guessing from the start. 

 

5 hours ago, JohnR725 said:

then a watchmaker lathe unfortunately on American pocket watches isn't an absolute must but just about. Even if you got the right staff you also find that the watch companies made staffs with the same part number with different pivots sizes. So you might have to reduce a pivots size or reduce the length sometimes they were made longer than ever supposed to be so you could fit them.

I'm no stranger to lathes and I can almost envision a watchmakers lathe in my future. That is, if I can come up with the cabbage to buy one. I'd love to have one. Even a used one if there is such a thing. a worthy one anyway. 

I'm working with a retired watchmaker who I've bought from before, who claims he is the one-stop shop for Hampden-Dueber parts, that he inherited the lot from two company-assigned watchmakers that stayed behind when Hampden moved to Russia. I'm just waiting to hear back from him, see if he's got answers and/or parts. he lives down in Canton, OH. Until then, I'm going to blend down the staking marks I found as Nucejoe recommended and see maybe if  that might be enough to engage pivot to jewels. 

[MechanicMike]

13 hours ago, jdrichard said:

make your own and you can adjust the heck out of it until it’s perfect.

then, there's the dilemma of removing old staff from balance to install a new one and I'd need a lathe for that too! this repair is growing legs just as I sit here and type! 

[MechanicMike]

Update: I polished  down the staking marks on the plate and the underside of the balance cock, and that did the trick. I've got some new matched jewels coming too for the heck of it. Might as well while I'm at it. Thanks everybody. My bud is going to be really happy. And I can breathe again.