Entire wheel train locks up when wound

[SndChsr]

Good day folks,

Coming up on 50 years old, I cannot afford to pull out much more hair out of my head so I came here for advice. I just finished restoring an Elgin Grade 313. Prior to installing the pallet fork, the entire train of gears moves freely when i nudge the mainspring barrel with a toothpick. 

i proceed to install the pallet fork and the balance, and when moving the watch rapidly from let to right the balance swings freely. However, when I wind the watch, everything becomes very stiff. Even if I have the balance swinging from moving the watch movement and then I begin to wind up the spring, the balance immediately  stiffens and comes to a halt. 

I also notice that none of the wheels...ie: 4th, 3rd or 2nd are moving while the watch is wound up. Even if I release the tension on the mainspring, I can no longer cause the entire train of gears to move while nudging the mainspring barrel.

The barrel bridge and the train bridge are not screwed too tight. All the pivots are correctly seated in their jewels and everything is oiled. I have replaced the mainspring with a new one as well. As stated earlier, after installing the mainspring barrel and all gears minus the pallet fork, and securing the bridges, all gears spin freely when nudged with a toothpick. Only after installing the pallet fork and balance, the entire train seems like it was welded in.

Any help would be much much appreciated.

Thank you!

[watchweasol]

Hello and welcome to the forum,  At the point it all locks up does the balance move freely when moved by hand, and does the fork/pallet move when done manually?  It is possible you have a worn/cracked jewel which allows a wheel to move under tension from the mainspring.  Remove the mainspring altogether assemble the train and check, if ok fit the fork/pallet. By applying tension with a tooth pick does the pallet/fork snap smartly when moved manually, if ok then fit the balance and repeat the above does the balance oscillate. What we are trying to achieve is validation at each stage with minimum power application. Also check for side play (shake)the gear train and fork/pallet.

[Nucejoe]

Faulty fork's engagement at either end, at escape wheel you might have pallets way out of adjustment, at the other end of fork a bent guard pin can do this, broken jewel to the fork arbour.

Remove the balance, wind ,  Does the fork jump when nudged, test both left and right jumps.

Can we see a close up of the pallets and guard pin?

 

[nickelsilver]

Is the balance engaging the fork at all? Is the roller jewel on the right side?

[SndChsr]

Thank you so much for the answers.

So I removed the balance. I gave the watch one turn wind and no movement. I removed the the fork and the train came to life. Soooo...it's the fork indeed.

A bit of history. This is not the original fork. During re-assembly, I noticed that one of the jewels was missing in the original so I sourced a fork from another Grade 313. I checked the part #'s and they matched. Prior to switching the fork, the movement did work. So looks like the donor is in fact the problem here. 

In the attached photo, does it seem like the jewels are maybe a tad too long? The one on the left in particular. I'm wondering of it is preventing the escape wheel from passing through. 

Now that I know who the culprit is, I need to hunt for a new fork. 

Also in the photos are the 2 forks. On the left is the donor replacement and on the right is the original with a missing jewel. They seem identical. I can't understand why the replacement would cause problems!

 

[nickelsilver]

If the fork is in the train can't spin. If the fork unlocks from an escape tooth the train will advance one escape tooth. If the balance is in, and the roller jewel is on the wrong side of the fork, it won't unlock the fork.

 

Check that if the fork is in, and you move it from one side to the other, the escape wheel advances. If it does, install the balance so the roller jewel engages the fork, and see what happens.

[SndChsr]

Problem solved folks!

Turns out my hunch was right. One of the banking pins was set too far inwards which in turn prevented the fork from having a wide enough angle to let the teeth of the escape wheel pass through. I turned the right banking pin a little more outwards and now the escapement is in full motion. Setting this thing in beat will be another story

Thanks to everyone who chimed in. Very much appreciated!

[JohnR725]

12 hours ago, SndChsr said:

another Grade 313. I checked the part #'s and they matched. Prior to switching the fork, the movement did work. So looks like the donor is in fact the problem here. 

hey unfortunate problem with watchmakers not familiar with American pocket watches and the parts manual. You have a particular watch you look up the part their mass-produced they're all the same they all interchange or do they? If you look at some of the YouTube videos for the American watch companies you'll find that a lot of the components are adjusted. Especially the older watches lots of things are adjusted to fit. If you look at the plates in your watch did you notice that they all have the same serial number? A lot of time shall find the balance wheel has the serial number inscribed on the balance wheel. That's because all the parts were adjusted to fit together. So even though you can get a replacement component usually anything related to the escapement has to be adjusted. Unlike modern watches were usually a pallet fork will interchange with zero problems

10 hours ago, SndChsr said:

Turns out my hunch was right. One of the banking pins was set too far inwards which in turn prevented the fork from having a wide enough angle to let the teeth of the escape wheel pass through.

movable banking pins an American pocket watches and actually a lot of older watches why are they there? Is a true the rumor that the watch companies put them there to entertain the watchmaker? Unfortunately not they serve a purpose. Because manufacturing wasn't that precise especially related to the escapement they needed to be adjusted for each watch. The primary purpose of the banking pins is for fork horn clearance. The normal procedure for escapement adjustment once you verify that everything visually is right would be to adjust the banking pins to get the horn clearance. Then you verify a guard pin finally adjusting the pallet stones. So yes you can move the banking pin but conceivably that will introduce other issues. Fortunately the pocket watches art that precise you probably won't notice perhaps

 

[SndChsr]

Thank you for your replies JohnR725. 

To answer your first question, yes, the numbers all did match on the movement parts, however I have serious doubts about the balance. The roller table and fork were different from all other 313's I've ever seen. This watch was such a mess that I decided to scrap that whole movement and just use another, spare 313 I had lying around which is in much better condition.

I had adjusted the banking pins on the spare movement as well because amplitude and beat error were an utter mess.

Finally managed to get the watch to 0.2ms and between +2/+4 sec per day in 4 positions. Not bad!

Thanks for your input!