jules jurgensen watch regulation

[mrpat2]

Id like some advice on regulating this watch. Its a Jules Jurgensen Movement and what Im not understanding is adjusting the regulation. In the photo you can see the part that you rotate, effectively making the hairspring longer or shorter. There is a notch in that piece diectly opposite the arm that retains the end of the spring. Is that notch supposed to line up with the plus and minus scale? If so its way off. The watch does run fairly slow. But, when I move it towards plus so that the notch is in range with the scale, the balance wheel stops. Also, there is another arm that kind of guides the spring and when I move the main lever, it moves along with it. Is this right? So that the position of the 2 arms is always the same? Thanks in advance for any advice.

 

[gmorse]

Hi mrpat2,

The arm on the left with the single 'rivet' in it is the balance spring stud. It should move independently of the other arm which is the regulator and alters the effective length of the spring. If you move the first arm, you're changing the beat, so when you move it more than a little the watch will probably stop; you must get it back in beat properly before you start moving the other arm with the two rivets, which is to adjust the rate. When the escapement is in beat, with no power on the mainspring and the balance at rest, the lever should be centralised between the two banking pins; you should be able to get it there roughly by eye to start with, which should at least allow it to run. Adjusting it more precisely really needs a timing machine. The scale on the balance cock refers to the regulator arm, not the stud arm.

Regards,

Graham

 

[karlmansson]

Doesn’t look like this particular movement has a lever that indicates on the + - scale. Maybe broken off, maybe design feature. Otherwise I agree with Graham. This type of design saves a LOT of fiddling about with adjusting best error.

 

[mrpat2]

So, when I move the arm with the single rivet, I change the effective length of the spring. I get that. But, when I move it, the other arm moves as well. This is the beat adjustment ( comparable to the tick-tock in a clock). If I want to keep it in beat but speed up the regulation, I would move the first arm independently of the second arm (one with 2 rivets). This gets kind a tricky to keep the 2nd arm staionary while I adjust the first. Do I have this right?

 

[Chris Radek]

Yes, they both need to be set correctly, and you are right, that the one that moves the end of the spring adjusts the beat, and the one that moves the pins adjusts the timekeeping.

If you are going to do this a lot, you should consider a timing machine, like one of the chinese clones that are pretty good. If you only need this one watch regulated, you should probably send it off to your watchmaker. These watches without microregulators are devilishly hard to adjust without a machine. The chance of making the small change you need without messing it all up is very low. With a machine they're fairly convenient.

 

[mrpat2]

Thanks it all makes sense now. Im used to clocks and setting beat etc. and the same theory applies here with the pallets and forks and the escapement needing to be centered, Im actually going to sell this watch, and Ill prob take it to a watchmaker if I cant get close. Thanks so much!

 

[gmorse]

Hi mrpat2,

So, when I move the arm with the single rivet, I change the effective length of the spring.

No, that one affects only the beat. The one with two pins is the regulator which alters the effective length of the spring and hence the rate.

Are you looking at this under reasonable magnification in good light?

Regards,

Graham

 

[mrpat2]

Its hard to see but I can make out that the arm with the rivet holds the end of the spring. So I know that one regulates the speed. The other is harder to see but I suspect it is attached to the balance staff so moving it affects the beat. This is why when I can cranked it around too much it stopped. When I put it back as close as I can it now runs reliably and Ive gotten close on the regulation watching it over 12 hours or so. Incidentally I took it today to a "watch repair" place in the mall. He claimed to have the beat error machine but he wouldnt agree to do just that. He wanted a complete cleaning etc. I said no.

 

[mrpat2]

Hold on a min. The arm with the 2 rivets: If the spring is allowed to oscillate about this point, then that is the "effective" length as any spring dimension plays no part, just sits there. SOunds like I need to study this a bit more and get a better look

 

[mrpat2]

Now its getting more interesting. After looking at some timegrapher videos, I get the concept of the beat error amplitude and all that. Now I found a phone app that shows the rate and beat error. I dont know how accurate but I was able to adjust the rate very close to a few sec/day by moving the arm with the 2 rivets. It dont change the length but the EFFECTIVE length as that is where the spring oscillates from. But, the app is showing a beat error of 4 ms. Not horrible, but I tried to move the arm with the one rivet a little either way but that value didnt change. If I depower the mainspring and let it rest the impulse pin should fall right in the center of the pallet forks right? and moving this end of the spring is supposed to change that correct?

 

[gmorse]

Hi mrpat2,

If I depower the mainspring and let it rest the impulse pin should fall right in the center of the pallet forks right? and moving this end of the spring is supposed to change that correct?

Yes, that is correct. If your app isn't showing a change when you move the stud, it may be a problem with the app. The beat setting, (by whatever method it's adjusted), and the rate setting are independent of each other. On watches without this movable stud, the beat is altered by turning the centre balance spring collet on the staff, which means removing the balance; the arrangement on your watch avoids the necessity to remove the balance each time an adjustment is required.

If the watch is significantly out of beat it can affect the amplitude, because the balance is not then moving through the same arc in each direction of its swing. A poor amplitude can result in a gaining rate, since the balance is taking less time to complete its oscillations.

Regards,

Graham

 

[Skutt50]

the impulse pin should fall right in the center of the pallet forks right?

I set the impulse jewel in the center between the banking pins. The fork is movable so if you use the fork as a guide you also need to check that the fork is in the middle betwee the banking pins when you do the adjustment.

 

[mrpat2]

Thank you all for the advice I now understand the mechanics of it. After adjusting the regulator last night, now 12 hours later its spot on. Im not going to attempt at this point adjusting the beat error, I dont trust the app that far. This one (its called watch accuracy meter) doesnt give the amplitude nor does it allow for setting the lift angle. So I think Im good at this point.

 

[gmorse]

Hi mrpat2,

After adjusting the regulator last night, now 12 hours later its spot on. Im not going to attempt at this point adjusting the beat error, I dont trust the app that far. This one (its called watch accuracy meter) doesnt give the amplitude nor does it allow for setting the lift angle. So I think Im good at this point.

That's good news. You can always come back to it later on, perhaps when you've acquired a watch timer.

Timing systems, whether separate machines or software, use the lift angle to calculate the amplitude, but that's all it's used for, and you can arrive at the value in other ways if you need to. For instance, a slow-motion video will tell you all you need to know.

Regards,

Graham

 

[karlmansson]

Now its getting more interesting. After looking at some timegrapher videos, I get the concept of the beat error amplitude and all that. Now I found a phone app that shows the rate and beat error. I dont know how accurate but I was able to adjust the rate very close to a few sec/day by moving the arm with the 2 rivets. It dont change the length but the EFFECTIVE length as that is where the spring oscillates from. But, the app is showing a beat error of 4 ms. Not horrible, but I tried to move the arm with the one rivet a little either way but that value didnt change. If I depower the mainspring and let it rest the impulse pin should fall right in the center of the pallet forks right? and moving this end of the spring is supposed to change that correct?

4ms is pretty bad for a wristwatch. Consider the frequency. The standard for watches pre 1960 is 18000bph, five times a second. 4ms becomes a rather hefty chunk of each beat. Since you are using an app I suspect you use an acoustic microphone? It is going to be hard for an acoustic mic to get a clean reading good enough to assess beat error in the sub ms range. I would consider 0.4ms barely passable after a service.

You have gotten great answers from several contributors! As a general rule: moving the spring (either in the balance cock or on the balance) changes beat error. Moving the pins of the regulator changes rate. It can also change a whole bunch of other things if your hairspring isn’t centered/terminal curve shaped correctly and the pins not straight/spaced correctly. But that’s a different topic more related to troubleshooting.

I concur with getting a timegrapher! Don’t know how I got by without one before.

Regards
Karl

 

[mrpat2]

Thanks again guys for all the advice. Anyone want to take a stab at the movement#? manufacture? Or even how old or what model this watch is? I think it unusual that there is no second hand