Elgin pocket watch, balance doesn't want to move freely.

[GregG]

Hello all,

I'm trying to finish up an Elgin pocket watch.  Everything seems fine after reassembly, except that the balance doesn't want to spin freely.  If I coax it with a tweezer, it won't rebound to it's resting state unless I really rotate it far.  And even then, it doesn't resonate, it just falls back to it's resting state.

The balance staff does not appear broken and the ends of the staff are straight and true.  The balance wheel is not fouling against the top plate, the barrel, or the regulator arm.  The hairspring is perfectly concentric.  The jewels are not damaged.

I thought maybe there was not enough headspace, so I shimmed the balance cock with 0.05mm, but that didn't really help.  I'm confused where this mystery source of friction is coming from.

[JohnR725]

how was the balance doing before the watch was disassembled?

Then in your picture the mainspring barrel looks different color than the main plate?

also when you're checking stuff make sure the balance wheel is flat everywhere. Because the movable arms one arm might be down in a might only touch in certain places perhaps.

[Neverenoughwatches]

6 hours ago, GregG said:

Hello all,

I'm trying to finish up an Elgin pocket watch.  Everything seems fine after reassembly, except that the balance doesn't want to spin freely.  If I coax it with a tweezer, it won't rebound to it's resting state unless I really rotate it far.  And even then, it doesn't resonate, it just falls back to it's resting state.

The balance staff does not appear broken and the ends of the staff are straight and true.  The balance wheel is not fouling against the top plate, the barrel, or the regulator arm.  The hairspring is perfectly concentric.  The jewels are not damaged.

I thought maybe there was not enough headspace, so I shimmed the balance cock with 0.05mm, but that didn't really help.  I'm confused where this mystery source of friction is coming from.

Have you visually checked for end and sideshake? 

6 hours ago, GregG said:

Hello all,

I'm trying to finish up an Elgin pocket watch.  Everything seems fine after reassembly, except that the balance doesn't want to spin freely.  If I coax it with a tweezer, it won't rebound to it's resting state unless I really rotate it far.  And even then, it doesn't resonate, it just falls back to it's resting state.

The balance staff does not appear broken and the ends of the staff are straight and true.  The balance wheel is not fouling against the top plate, the barrel, or the regulator arm.  The hairspring is perfectly concentric.  The jewels are not damaged.

I thought maybe there was not enough headspace, so I shimmed the balance cock with 0.05mm, but that didn't really help.  I'm confused where this mystery source of friction is coming from.

This area here looks like a lot of gouging ( raising material to increase endshake) has taken place.

[GregG]

5 hours ago, JohnR725 said:

how was the balance doing before the watch was disassembled?

Then in your picture the mainspring barrel looks different color than the main plate?

also when you're checking stuff make sure the balance wheel is flat everywhere. Because the movable arms one arm might be down in a might only touch in certain places perhaps.

Prior to disassembly, the balance was doing the same thing (i.e. only returns to its resting state), but without as much friction.

I will double check the flatness of the wheel.

4 hours ago, Neverenoughwatches said:

Have you visually checked for end and sideshake? 

This area here looks like a lot of gouging ( raising material to increase endshake) has taken place.

I haven't visually checked, though by feel, I can gently shake it back and forth a little.  Though I was always a little leery on my ability to determine sideshake/endshake, because I could never tell if I was truly lifting the balance up and down, or just rocking it back and forth.

[Neverenoughwatches]

20 minutes ago, GregG said:

Prior to disassembly, the balance was doing the same thing (i.e. only returns to its resting state), but without as much friction.

I will double check the flatness of the wheel.

I haven't visually checked, though by feel, I can gently shake it back and forth a little.  Though I was always a little leery on my ability to determine sideshake/endshake, because I could never tell if I was truly lifting the balance up and down, or just rocking it back and forth.

A visual inspection would make for a more accurate analysis of what it happening.

32 minutes ago, GregG said:

Prior to disassembly, the balance was doing the same thing (i.e. only returns to its resting state), but without as much friction.

I will double check the flatness of the wheel.

I haven't visually checked, though by feel, I can gently shake it back and forth a little.  Though I was always a little leery on my ability to determine sideshake/endshake, because I could never tell if I was truly lifting the balance up and down, or just rocking it back and forth.

For more reassurance against internal movement damage, a thin artist's paintbrush makes for a ideal testing implement.  However the hair end of the paintbrush is far superior

[JohnR725]

5 hours ago, GregG said:

Prior to disassembly, the balance was doing the same thing (i.e. only returns to its resting state), but without as much friction.

I will double check the flatness of the wheel.

16 hours ago, GregG said:

I'm trying to finish up an Elgin pocket watch.  Everything seems fine after reassembly, except that the balance doesn't want to spin freely. 

in watch repair cleaning doesn't always fix everything. As you had a pre-existing problem it would've been preferred to figure out what the problem is before cleaning and going to final assembly. Because basically still have the same problem as it's not been repaired.

[GregG]

So I checked the watch again. And I think there are a few factors at play here.  First, I think the hairspring stud was rubbing against the hairspring.  The terminal curve didn't really sit above the rest of the hairspring, so I gave it a little gentle persuasion.

Second, the lower cap jewel setting doesn't sit perfectly centered in the seating, because the jewel setting is just a hair smaller than the seating, which allows it to wobble left and right when not secured.  This means that the upper hole jewel wasn't perfectly centered above the bottom hole jewel.  I loosened the setting screws, and that gave it a little additional headspace, and to re-center itself.

Then I re-shimmed it with the 0.05mm sheet.  Now it's rotating much more freely.  Just rotating the movement in my hands will allow it to swing once or twice, whereas before, it didn't even swing once.  So it's an improvement overall, but I'm still trying to track down the source of the issue.

As it is now, there is more probably more side shake and end shake than there should be, but not grossly so.  The pallet snaps back and forth when coaxed, so I'm pretty sure there's a good amount of energy making it to the impulse pin.

[JohnR725]

21 hours ago, GregG said:

Second, the lower cap jewel setting doesn't sit perfectly centered in the seating, because the jewel setting is just a hair smaller than the seating, which allows it to wobble left and right when not secured.  This means that the upper hole jewel wasn't perfectly centered above the bottom hole jewel.  I loosened the setting screws, and that gave it a little additional headspace, and to re-center itsel

let's look at something?

https://pocketwatchdatabase.com/search/result/elgin/15057806

21 hours ago, GregG said:

there is more probably more side shake and end shake than there should be, but not grossly so

we know from looking up the main plate the marks on the main plate itself are were somebody tried to adjust the end shake. The most common reason for doing it is not having access to a lathe when changing a balance staff. In other words the pivots are probably too long and they needed the short. Then there is the other problem

let's look up your balance staff 857 is my favorite balance staff for Elgin because it's one part number and I have a list below of the balance staff dimensions.

so as you can see one part number four separate staffs. The new in the old style and the most common of all American pocket watch balance staffs pivots size differences. Then sometimes pivots are longer than they need to be because they were supposed to be fit by shortening although that's not always specified so it depends on things like aftermarket staff etc.

so will make an assumption somebody change the balance staff and the pivots are broken more than likely the balance jewels were broken.

then the part number for the balance staff jewels of both upper and lower part of the same x443. I suspect if you measure your hole jewel still find a not quite the right physical size as they might've substituted something else. Plus of course on the holder watches there tend to be variations like the balance staff variations even though it doesn't say there's variations there could be variations