Review of English pocket movement

Andrew Babanin

There's the last watch I worked on. Here there's my lovely English pocket movement.

Fig 1. Just a blank dial

Its case was made of gold so it had been lost in time. The dial is in pretty good condition except on the crack at 12. There was a lug to fix the movement to the case. Maybe smb dismounted it with no care and cracked the dial a bit. The movement is covered with special hood. One turn of the blued arc clockwise - and it's open, CCW - closed. So I removed the hood to show you the guts. Unfortunately, I do not have any info about manufacturer except two letters "TF" (what date can it be?) on the hood and its serial number 94579. The movement came to me in pretty good condition, so I even hesitated whether any person serviced it. The problem was with the balance wheel - the balance rim and roller rotated freely on the axis, also its hairspring was deformed. The whole movement was dirty with old oil.

Fig 2. The movement is covered with hood

This movement is based on a fusee, so the only way to release the mainspring is a special ratchet wheel under the dial. Normally it used to make the mainspring be wound at 1-1,5 turns (Its principle is close to the Maltese cross - where we allow the mainspring to work in the special range: not to be fully released or wound). One of fusee aims also not to let the mainspring to be released or full wound. Changing length of the chain we can find the moment when we use only working area of the mainspring.

Fig 3. Pretty nice movement inside

The movement was full wound, so I inspected it carefully before any step. I decided not to release the mainspring traditionally because of the risk to damage it. So I had to remove the balance wheel first and make its repair. After centering the impulse jewel and improving the hairspring I mounted the balance unit back. I had to give some benzene to all pivots to make the watch running. And after some manipulations it became working. At first the amplitude was very poor, so it stopped twice. Then the matters went better - it worked about 28 hours before stopping. Afterwards I was able to release the mainspring without any trouble (just repeat: with a special ratchet wheel under the dial). Then it was not a problem to disassemble the whole movement. I was amazed with the quality of finishing - all parts, including brass wheels were polished and shined brightly like a mirror.

Fig 4. The fusee chain

After careful cleaning and lubricating I assembled the movement. The only problem was to mount the chain back - if the mainspring is released - the chain should be on the barrel, not on the fusee. But in this condition it tries to slip from the barrel surface. After several attempts I mounted all wheels, the pallet fork, the fusee and the barrel with a coiled chain and covered it with the bridge. I also didn't forget to wind the mainspring on 1,5 turns.

Fig 5. Another view

After some tunes the movement works perfectly. "Perfectly" means that the watch gains 5 seconds per day! After a week testing it was about 30 seconds gaining. Pay attention that balance rim is made of solid gold! There's no any temperature compensation device.

Fig 6. The balance rim is made of solid gold. As to the endstone - it's a diamond.

What else? As I mentioned before, in post .... all watches of that period had no setting square at the back. So if you want to set time - just open the glass, find a square on the minute hand and using the key set the time. Also notice that escapement wheel has two cap jewels - quite rare for that period. As to escapement - traditional English one (not Swiss).