Secondhand arbor slightly bent, query

NEW65

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Nov 17, 2010
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Just a query. I'm working on a hermle movement with the secondhand feature. The long arbor that projects outwards and through the dial, has been very slightly bent. It is slight though but you can see it wobble slightly when allowing the time train to run.
I am just wondering if this will cause a problem. Obviously it has been caused by an heavy handed individual trying to locate the seconds hand!!!
I just wonder if its fine to leave and use as is?
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bruce linde

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straight is straight. bent is bent. can't see how much bend there is, but if spacing is tight between second hand and dial that might be enough to stop the clock. if the bend happens before or while the arbor is passing through the pivot hole there is inevitably going to be some additional friction. since the goal is to remove (as much as possible) any unnecessary friction, my vote would be for straightening. that said, it might be possible to remove the slight bend without having to disassembly, just by nudging the arbor gently... but if at all in doubt just disassemble, straighten and then put it back together.
 

Willie X

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If you are a good 'tapper' you can straighten it in place using a small hardwood block. A 1" x 1" x 6" block is good for many purposes. Willie
 

bangster

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Iffen the seconds arbor is the escape wheel arbor (usually is) it would be a good idea
to straighten it and eliminate friction, since the ew is where the rubber meets the road.
 
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R. Croswell

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If the extension is a smaller diameter than the part that passes through the plate, it is probably bent at the base of the smaller diameter part. If so, it is probably not contributing any extra friction. There is always the possibility that it will snap off when you try to straighten it. Of course there is the argument that it bent before and didn't snap, so it should bend back, but then it has already been bent once so be gently and accept the risk or leave it alone if it is only a slight bend and the seconds hand isn't hitting anything.

RC
 

Willie X

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You never know how many bends might be left in there. :)

Two points: don't bend it but once, by tapping only one tap at a time, in slightly increasing increments of energy. Don't apply energy at the tip of the shaft, go about 1/3 the way toward the root of the bend. This will help prevent the dreaded 'S' bend.

Willie X
 

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