This pic is captioned: Here you can see that one side of the upper point is completely worn away. You can also see where the lower point actually started wearing away the armature after eating through the side of the point. The unused side of the point is in very good condition. (It should be, since it wasn't used. The points must be realigned to get the clock running again, no matter what. That's the hard part to do properly. You cannot just "bend" the armature. But if we do realign the point, and if we then filed them down, the clock would be operable again. The problem is that then you have about half the point surface area you should have, so the points will wear themselves down again prematurely. That solution would be perfectly ok if you did not want a 24/7 365 operation. The challenge here is 1) to realign the points without doing any other damage to the clock, and 2) then protect the points to minimize the effects of future wear. And: Your friend's point is well taken, but the reason it won't work in our case is that the clock coils represent a highly inductive load, which generates a very high back EMF voltage across the points when the points open. The coils in these clocks would typically be about 10 mH, which results in an arcing EMF of about 3000 volts. That's why the points here are not made of copper in the first place. The better clocks, like Borg, used tungsten points so they could stand up to the inductive load. Even if we could resurface the points with copper I'm afraid they would fail in a matter of only a few weeks. The difference in the central office, of course, and the reason copper points worked there was the absence of inductive loading on the voice circuits. Ron Water's idea about installing an on-off switch might be good, but, I've already got a lot of wiring going on under the dash, with the auxiliary starter, the rear speaker fader switch, and the FM converter's wiring. ************************************************************* To unsubscribe or set your subscription options, please go to http://lists.psu.edu/cgi-bin/wa?SUBED1=l-forwardlook&A=1 Attachment:
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