Doing a restoration of this clock that had been stored for 30 to 35 years. It was bought about 1955 one owner. To start, it is a plate 1395 4 ball pendulum. I have done a full overall and inspection of the movement. Complete tear down, cleaning and polishing everything, plates, pivots, bushings, gears, pallets (did not remove pallets from escape) and all the rest of related parts. I then checked all arbors for straightness, the only gear out in the slightest was the minute arbor by .0015 now sitting at .0005. All escape teeth are good all equal size, and ready to be re-installed. Parts that I replaced are the mainspring with a new 20 x 38 and a new complete unit suspension spring SU Unit 13c at .0033 both from Horolovar. Put it back together, checked before escape arbor to make sure all movement was good with the gear train and it was. Added escape and hand checked drop and lock with a slight winding of the spring, all good. Added the rest of the components and put it in beat. Started the test period and after running for a day I noted that the amplitude of the pendulum was changing as much as 50 degrees within an hour. So I sat down and every 5 minutes noted where the pendulum was on the scale I laid out on the base. Note picture of what I found. This continued exactly the same for the two hours I watched it (I'm actually kind of patient). My thought was there is a lose of power at the same time every hour. Must be the motion works (I'm thinking) so I remove the hour hand and set it to run again. It got much better, now there is only a difference of about 20 degrees in the hour. So I remove the motion works completely. I has been running for a full week at a whooping 375 degrees both clockwise and counter clockwise and very strong. So I put it all back together and the same thing, but while watching it this time, I noted a ⅛" space that the hour wheel can move in and out freely on it's axle screw. Can't figure if that has anything to do with it but it is the only thing so far that I've come up with. Another thought I'm wondering if there was a washer there under the secure mounted wheel to the front place to take up this space but I don't see that on any drawings? I'm at a loss, if anyone has any suggestions I would be happy to check them out. Another odd thing, under the hand nut was two (2) concave hand washers. If I remove one, it does not get tight enough to lock the minute had into the motion works. There is no face plate binding either also notable on the picture.
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