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Discussion Starter #1
6497s and 6498s don't officially hack (the fourth wheel, and by association the subseconds hand doesn't stop turning when the crown is pulled to the setting position, which makes syncing the seconds hand almost impossible). It has been reported that one can fake a hacking behavior by putting back pressure on the crown in the setting position. Without actually rotating the crown, and therefore without actually changing the hour/minute setting, you can use this trick to make the fourth wheel stop turning. When this works, you can actually see the balance rapidly spin down and stop, everything completely stops. The moment you let go of the crown, everything starts again (in my experience you can deliver a slightly more solid initial "kick" to the seconds hand by rotating the crown forward just enough to fill the gear-slop). In this way, you can sync the seconds hand on a nonhacking movement, or least you can on the 6497 and 6498.

I have several 6497s and 6498s and some clearly support this trick while others clearly don't. The ones that work, really really work. The halting effect is almost immediate, the effect is total (all motion stops) and the effect is just as easily and unambiguously released. Likewise, the ones that don't work, really really don't work at all, not even the tiniest little bit. With a little back pressure nothing happens at all. The obviously tempting stronger back pressure consequently begins to turn the hour and minute hands the other direction, and even at that point the fourth wheel and balance still continue forward unabated at full speed.

I haven't taken these movements apart yet to see if there is a difference, but I thought they should all be mechanically identical. Does anyone understand what's going on here?

The movements that support this behavior are an unbranded "swiss" movement (from one of the common gold Arnex pocket watches from the early 80s) and a SeaGull 6497 and a SeaGull 6498. The movements that completely fail this behavior are a Hangzhou 6497 and a Hangzhou 6498.

Any idea what accounts for the difference here?

Thanks.
 

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Tightness / looseness of the cannon pinion is what accounts for the difference, probably. I can't get any of my Arnex - era Unitas ones to stop.

6498ghoul
 
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Discussion Starter #4 (Edited)
Coo. Thanks. I was just wondering what accounts for it. Good to know.

Ummm, so I guess this is actually a friction connection as opposed to a gear connection, is that right? Is this sort of thing adjustable? I'm guessing not.
 

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Coo. Thanks. I was just wondering what accounts for it. Good to know. Ummm, so I guess this is actually a friction connection as opposed to a gear connection, is that right? Is this sort of thing adjustable? I'm guessing not.
YOU need the Bergeon Cannon Pinion Tightening Tool.

P.S. KW - all is forgiven. Please come back and entertain us in F6.
 

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Coo. Thanks. I was just wondering what accounts for it. Good to know.

Ummm, so I guess this is actually a friction connection as opposed to a gear connection, is that right? Is this sort of thing adjustable? I'm guessing not.
It is a friction connection that allows the works to rotate the cannon pinion (that the minute hand is attached to, and that drives the hour wheel by gear reduction) to show the time but also allows you to move the hands to set the time - by overcoming that friction. If it's too loose the hands may "spontaneously" decouple from the works and you end up with the wrong time displayed. Too tight and you can't set the time without torquing on the movement - in a bad way. The "poor man's hack" is applying just enough resistance to the train that it stops (without physically stopping the balance, which is what a hacking movement does). You can adjust the "dimple" in the cannon pinion (that provides the friction) in a number of ways, some of them horribly barbaric. As Pithy says, there are specific tools for this or you can use specific punches and anvils in a staking set, etc. Also, a new pinion is under $10, so if you really want to experiment this isn't an expensive mistake in the making.

6498ghoul
 

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I always get a bit of a chortle out of the threads, I was setting my watch like this starting around 1970/71. Thought it was normal.

But - you can of course 'back up' the second hand if need be. Do that with most hacking movements! With them you just hace to wait for the second hand to the "setter" watch (sure that's not the right word) to come around again. A potential savings of 59 seconds!
 

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is this bad for the movement, do put back pressure on the crown and stop the movement?
 

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It is not. I have been doing this for many years with non-hackable movements with no ill effect.

My Omega Speedmaster Moon Watch actually stated to do this in the owners manual.

I have always found that it's easier to do this when the watch does not have too much of a power reserve built up.

I also take it easy when doing this, trying to show some mechanical sympathy, never forcing anything and just really trying to keep the second hand still as opposed to going full force and making the second hand go backwards significantly.



is this bad for the movement, do put back pressure on the crown and stop the movement?
 

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Better check if the respective 6497/8 is fully wound or empty. In fully wound movement this hacking trick will be difficult up to impossible.

But who needs hacking anyway? I find it to be time consuming so I do not care about it anymore. I would like a watch with minute detent (automatically align with the second hand) though. Yet, except some independent (Volker Vyskocil) I see no maker trying to implement such complication.
 
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