PeteM Posted July 26, 2012 Report Share Posted July 26, 2012 I was just wondering if the A7750 clone had a winding point/station as some Swiss movements do? I have always been told on here that you shouldnt manual wind an A7750 but there is a different POV when it comes to the ETA etc.. Any definitive info would be much appreciated Thanks in advance Link to comment Share on other sites More sharing options...
FxrAndy Posted July 26, 2012 Report Share Posted July 26, 2012 You can wind them but the transfer gears are weak and you risk damage. So it is recommended that you don't On a Swiss one the gears are better and you can get spares Link to comment Share on other sites More sharing options...
PeteM Posted July 26, 2012 Author Report Share Posted July 26, 2012 You can wind them but the transfer gears are weak and you risk damage. So it is recommended that you don't On a Swiss one the gears are better and you can get spares Makes perfect sense mate.... Thank you for taking the time to reply I had thought it might be a quality issue but for the life of me I couldnt find anything that said why.... Funnily enough Panerai say avoid doing it unless its dead.... then only a few turns But others say crack on... you cant damage it.... or even over wind it... Problem with me is I only understand basics... so I cant see the movement working in my head as I do something to it...therefore cant work out the consequence.. Not for the want of trying... it just dont settle in my head... As an aside and if you dont mind me asking... If you have a big secs hand on something like the Hublot 48mm Kings...its very hacky and on the rep can jump around... (It can be hacky on gen but not as much I think) So is that an issue with the length/weight of the hand on the poorer quality gears in the clone? Link to comment Share on other sites More sharing options...
FxrAndy Posted July 26, 2012 Report Share Posted July 26, 2012 If you have a big secs hand on something like the Hublot 48mm Kings...its very hacky and on the rep can jump around... (It can be hacky on gen but not as much I think) So is that an issue with the length/weight of the hand on the poorer quality gears in the clone? yes on both counts Link to comment Share on other sites More sharing options...
Jkay Posted July 26, 2012 Report Share Posted July 26, 2012 I could have sworn that Zig said both the Swiss and Chinese 775x had weak winding gears. Link to comment Share on other sites More sharing options...
PeteM Posted July 27, 2012 Author Report Share Posted July 27, 2012 Thanks Andy Link to comment Share on other sites More sharing options...
Rolexman Posted December 30, 2012 Report Share Posted December 30, 2012 I had thought it might be a quality issue but for the life of me I couldnt find anything that said why.... Funnily enough Panerai say avoid doing it unless its dead.... then only a few turns But others say crack on... you cant damage it.... or even over wind it... Problem with me is I only understand basics... so I cant see the movement working in my head as I do something to it...therefore cant work out the consequence..It has nothing to do with the quality of the gears. It has to do with the gear ratio. As a metaphor I will use a mountain bike. 1. Say you put the back in a high gear (big wheel) and the front in a low gear (small wheel). You can peddle very easily up a steep hill right... -->That's how they make it possible for the rotor to wind a powerful main spring very easily. 2. Now say you want to peddle up that same hill but you change gears the other way around (small in the back and big in the front). Going up that hill would almost be impossible giving the strength our legs can provide. Now if we hypothetically could mount a v12 Chevy block on the front gear and would give full throttle what would happen you think?.... You would strip the teeth (most probably on the big gear) as it is not calculated for that amount of torque. It's a matter of physics. -->That's exactly what happens on the 7750 if you hand wind it too fast. That's right... You can hand wind it all you want as long as you do is slow in order not to strip the teeth on the intermediate winding wheel (so low torque). Otherwise your hand wind will be like the Chevy V12 in my example. On over winding a 7750 I can be clear. That is simply not possible as the main spring has a bridle (slippage system) like all automatic watches. If the tension build up by the main spring gets too much the bridle will slip en thus letting off tension. Off course this only applies if the main spring and barrel walls are greased appropriately. As an aside and if you dont mind me asking... If you have a big secs hand on something like the Hublot 48mm Kings...its very hacky and on the rep can jump around... (It can be hacky on gen but not as much I think) So is that an issue with the length/weight of the hand on the poorer quality gears in the clone?It has nothing to do with the weight of the hand. Normally two issues can cause it. A poorly finished tilting pinion or a weak chrono second wheel tension spring. The stutter comes from the slack between the teeth of the gears. I have seen a lot of genuines with the same stutter on the chrono second hand (that's the hand you are talking about). With our reps it normally is the tilting pinion and the poorly finished teeth.. sometimes in combination with the spring. With genuines it almost always is the tension spring. But rest assure. I does not affect time keeping or reliability in any way. Do a search on google: "stutter second hand 7750 " 1 Link to comment Share on other sites More sharing options...
Winno Posted December 30, 2012 Report Share Posted December 30, 2012 Great info Rolexman, thanks..... Very interested in the 7750 movement..like it a lot... Link to comment Share on other sites More sharing options...
PeteM Posted January 9, 2013 Author Report Share Posted January 9, 2013 Thanks so much guys for the great replies.... The analogy was brilliant thank you and so clear..I could visualise it as I read it.. As always you cant beat this place for great guys and great info...Thank you Link to comment Share on other sites More sharing options...
watchman12345 Posted January 10, 2013 Report Share Posted January 10, 2013 Good thread. Link to comment Share on other sites More sharing options...
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