Zodiac Talk => Ask BWG! => Topic started by: jon p on January 20, 2014, 08:46:15 AM

Title: zodiac GMT
Post by: jon p on January 20, 2014, 08:46:15 AM
my gmt starts right up when moved and keeps good time. my problem is the crown is very tight when i try to manual wind, so tight i am afraid i will break something doing a manual wind. when the crown is pulled out, different story, very light touch to set hands. it IS a "push to set date" quick set. should i worry?!
Title: Re: zodiac GMT
Post by: Ultra-Vintage on January 20, 2014, 08:04:11 PM
Yes, it is a concern.  When a watch gets that way you do not want to keep pushing it as you are likely to strip some of the winding parts.  There are three things that contribute to the difficulty in winding a watch movement like those in the Seawolf and GMT: condition of/lubrication of winding parts, resistance of mainspring in the barrel, and the friction of the reverser wheels against each other in the automatic assembly.  One or all of those is causing the issue, and it needs to be addressed.
Title: Re: zodiac GMT
Post by: jon p on January 20, 2014, 10:55:19 PM
thanks for your advice, i knew something was wrong. have to consider a service.
Title: Re: zodiac GMT
Post by: rdenney on January 21, 2014, 10:05:55 AM
Jon, my understanding (and what I feel and hear) is that handwinding these movements really spins up those reverser gears in the autowinder. Any undue friction at all in those gears will make it a struggle because of the leverage. I have an Ebel that uses the same ebauche, and it had the same problem with excessively stiff hand-winding. A service by BWG solved that problem. Considering the vastness of my Ebel collection (16 and counting between my wife and I), that vintage 60's model is really valuable in  my collection, and it's wonderful to have it working properly.

Rick "noting that Ebel used a recessed flush crown with the obvious intention that the watch would not be hand-wound" Denney
Title: Re: zodiac GMT
Post by: jon p on January 22, 2014, 04:15:31 PM
my other GMT ths been servived within 2 years hand winds very smooth / easy, thats why this one concerns me. UV hit the nail on the head, get it serviced and for now dont force it. WILL DO!!!
Title: Re: zodiac GMT
Post by: incountry on January 22, 2014, 09:33:32 PM
Thanks for bringing up this topic Jon.  One of my GMT's seems to be getting a little stubborn when I wind it and now I guess I know what I have to do with it.    :shuc