Getting old oil out
A while ago, I asked the man who was servicing my car which was the best oil to use. He replied that he wasn't all that fussy about which oil you
put in as long as you got the old oil out. The old oil contains all the dust, grit and particulates that have accumulated since the most recent oil
change. And it's the same with clocks: adding a bit of oil to an old clock might get it going for a while, but you'll do more damage than good in
the long term unless you get the old oil out. And that's exactly what we do on a normal service - or so we say. But there are two important bearings
on an average eight-day English longcase which are usually ignored. These are the pulley bearings. The pullet stirrups are usually riveted to the ends of
the pulley arbors, and not many repairers would recommend dismantling the rivets each time a clock gets overhauled. So - how do we get the old oil out?
The question becomes even more important if there is a chance that while you have been polishing the pulley you might have got a bit of polish deposit
on the bearings.
The only hope of getting some or most of it out is probably to use an ultrasonic cleaning tank. The cleaning fluid will get right into the bearing, dissolve the muck and wash it out. That's the theory anyway. Unfortunately it doesn't always work very well, so we need to help it. Make up a small ring with a notch out of it, as shown in the diagram. If you place the pulley on top of this ring in the cleaning tank, with the stirrup lying in the notch, the bottom end of arbor is not supported, and the dissolved muck will be able to fall out of the bearing to the bottom of the tank. I use a couple of old French barrels for the purpose. These pulley pivots are probably the most highly stressed in the whole of the clock; yet they endure twice the force that the great wheels' pivots endure, yet are only a fraction of the size. Ideally, I'd like to put some graphite grease on to them, but this is not possible as it will not flow. I oil them with normal longcase oil, but have long thought that turret clock oil might be more appropriate. Does anyone agree?
Jaques O'Toole, UK
