Jack1024 Posted November 5, 2009 Report Share Posted November 5, 2009 (edited) It seems clear to me that we have a new revision of the 5.4mm DG2813 (the 4813 is about 4.6 mm) on the rep scene. This probably has happened due to the ETA shortage. Check this out: 21J movements from my junk drawer: All three - note the size of the balance wheels: For the next pics... take note the edge of the balance to the edge of the movement chassis. The pics are a little blurry (iPhone...SORRY) but I think they show my point. Known Slow Beat 2813 (Had a typical 21j tick-tock sweep): Sold to me as fast beat (I don't believe it for a second, had a VERY lumpy sweep, even worse than the silver one) Known 28800 beat rate (I have another one just like it in my SSD.. the sweep is virtually indistinguishable from ETA) Josh/Andrew's 21J GWSD (Claimed to be 28800) What do you guys make of that? Edited November 5, 2009 by Jack1024 Quote Link to comment Share on other sites More sharing options...
alligoat Posted November 5, 2009 Report Share Posted November 5, 2009 I don't think the size of the balance wheel has anything to do with the beat. And I think the only real way to check the beat is to put it on the machine, like the one your watchmaker has! Quote Link to comment Share on other sites More sharing options...
Jack1024 Posted November 5, 2009 Author Report Share Posted November 5, 2009 (edited) I don't think the size of the balance wheel has anything to do with the beat. And I think the only real way to check the beat is to put it on the machine, like the one your watchmaker has! Of course it does! How do you think you regulate the watch? By moving the center of mass of the balance further or closer to the axis of rotation. Closer is faster, farther is slower. You can see this with the gen rolex movement with the microstella screws. When they are unscrewed, the center of mass moves closer to the balance axle (AKA escape wheel pinion), speeding up the beat. When they are screwed in the center of mass moves outward, slowing it down. The ETA (and the 21j also) has a more complex way of doing this, the balance mass is actually movable via the regulator. Lets take the example of a pendulum, which is in effect what the balance is, just a circular one. If you make the pendulum longer (or the balance wider, center of mass outward) it cycles more slowly. If you make it shorter (or the balance more narrow, center of mass inward), it cycles more quickly. Ideally you have the mass in exactly the right place so that the watch beats at exactly 4 hz (in the case of a 28800 bph movement) From there it is all reduction gearing through the wheels to make the second hand move at 1 RPM, the minute hand 1/60th of an RPM, and the hour hand move 1/3600th of an RPM. All from a balance that oscillates at 4 times per second (28800), or 3 times per second (21600). All of this is driven by the mainspring which both drives the balance oscillator, and controlled by it, via the escapement mechanism. Jack Edited November 5, 2009 by Jack1024 Quote Link to comment Share on other sites More sharing options...
Jack1024 Posted November 5, 2009 Author Report Share Posted November 5, 2009 (edited) I should add it is also possible to speed up the beat by stiffening up the hairspring. And in a way alligoat, you are right. Despite what we keep hearing, size doesn't matter, but mass does. I do agree that the only way to be sure is put it on a machine that is capable of measuring the beat. You can hear the difference of the 'tick' between 21600 and 28800, but measure it accurately... no way. Jack Edited November 5, 2009 by Jack1024 Quote Link to comment Share on other sites More sharing options...
If you see Kay Posted November 5, 2009 Report Share Posted November 5, 2009 yes, you can definitely hear the difference and see the difference in beat over at 21,6 and a 28,8 movement. also, if you have a camera, set the exposure to 1 second. You should be able to "see" the ticks. Quote Link to comment Share on other sites More sharing options...
offshore Posted November 6, 2009 Report Share Posted November 6, 2009 Yes, Hi Beat 2813's do exist...they are a special build. There is a MOQ (200), build time is up to 1 month, and you would go ballistic if you knew the price! Offshore Quote Link to comment Share on other sites More sharing options...
P4GTR Posted November 6, 2009 Report Share Posted November 6, 2009 Must be nice to have the inside scoop! So... Whats the price? Quote Link to comment Share on other sites More sharing options...
offshore Posted November 6, 2009 Report Share Posted November 6, 2009 How many ya want? Makes a HUGE diff! O/S Quote Link to comment Share on other sites More sharing options...
Jack1024 Posted November 6, 2009 Author Report Share Posted November 6, 2009 Well if the MOQ is 200, how about 200? Then lets go big or stay home... how about 20k? Just for fun.... Quote Link to comment Share on other sites More sharing options...
offshore Posted November 6, 2009 Report Share Posted November 6, 2009 How 'bout a hundred each, just for fun. O/S Quote Link to comment Share on other sites More sharing options...
Jack1024 Posted November 6, 2009 Author Report Share Posted November 6, 2009 (edited) I could see that for 200, a pretty small amount to spool up the assembly line for. But not for 20k of them.... I would think they should be about $4-5 bucks a pop after about 3-5k of them to pay for the spin up. I would guess that the only differences would be the hairspring, the balance and the escape wheel, wouldn't the rest of the parts be the same as the standard beat model? How 'bout a hundred each, just for fun. O/S Edited November 6, 2009 by Jack1024 Quote Link to comment Share on other sites More sharing options...
Member X Posted November 6, 2009 Report Share Posted November 6, 2009 This is a great thread Thanks for all the info posted! Quote Link to comment Share on other sites More sharing options...
kbh Posted November 6, 2009 Report Share Posted November 6, 2009 Like most other movement series, including most Eta movements, they usually bump up the beat rate as the manufacturing abilities increase. It's only a matter of time. Quote Link to comment Share on other sites More sharing options...
Jack1024 Posted November 6, 2009 Author Report Share Posted November 6, 2009 Like most other movement series, including most Eta movements, they usually bump up the beat rate as the manufacturing abilities increase. It's only a matter of time. I have to tell you that the 4813 (like the one on the right in the pic above) is awesome! I have it in my SSD (it replaced the silver dud on the left, which doesn't hack) and it is < +/- 2 seconds a day off. I did regulate it, but that took exactly one round with the tiniest adjustment on the arm to slow it down from about 7 seconds a day fast. The sweep is as smooth as butter. This is seriously impressive for a $25 movement (ETz has'em). I am always happy getting good stuff for cheap! J Quote Link to comment Share on other sites More sharing options...
FxrAndy Posted November 6, 2009 Report Share Posted November 6, 2009 A point to note for all, as of the last discussion on these movements the only vendor for the 4813 witht the longer canon pins to fit sub reps was eurotimez, if you order one from cousins ect it may not fit due to hand height. Quote Link to comment Share on other sites More sharing options...
offshore Posted November 6, 2009 Report Share Posted November 6, 2009 Andy, As stated, they are special build. There are some being run in the system at the moment, and I will have access to a few in under a month, both long pinion 4813's and 2813's, both High Beat. I know of at least one other dealer who has them, and anyone in the scene can commission a run relatively easily; it just takes patience and $$! Offshore Quote Link to comment Share on other sites More sharing options...
FxrAndy Posted November 6, 2009 Report Share Posted November 6, 2009 Sorry OS i was just thinking about the few who had bought the wrong one, if you will have them soon then good to know. Quote Link to comment Share on other sites More sharing options...
Jack1024 Posted November 7, 2009 Author Report Share Posted November 7, 2009 A point to note for all, as of the last discussion on these movements the only vendor for the 4813 witht the longer canon pins to fit sub reps was eurotimez, if you order one from cousins ect it may not fit due to hand height. Not only that, it is likely you will get the slow beat version. (middle movement) J Quote Link to comment Share on other sites More sharing options...
EuroTimez-Neo Posted November 7, 2009 Report Share Posted November 7, 2009 Jack1024: You've made a very good point for the movement details. I'm sure a lot of members that are wondering the difference now know. I've had a couple people inquiring me the difference between the 2813 and 4813 movements.. I'm sure this post will be a very good reference to anybody that inquires about it again.. Regarding the DG 4813 movements, we just ran out of stock a couple days ago, however please to let everybody know we have order another 200 movements for the same price of 25 usd. You can see them on our webstore at http://www.eurotimez88.com/product_info.php?products_id=3537&osCsid=6f5ee4225945a11c2816234cd8114730 which I guarantee are Hi beat 4813 movements.. thx again for the good review... Quote Link to comment Share on other sites More sharing options...
Jack1024 Posted November 7, 2009 Author Report Share Posted November 7, 2009 (edited) Hi Guys, For the $98 DRSD that Josh & Andrew are selling, here is the time-o-graph pic from Josh's website showing the 28800 beat. Check it out: If anybody knows more about how to read this thing, please chime in. I'd like to understand how accurate this movement is. I am personally very happy to see this inexpensive choice in movements appear. The 21J has always been fairly solid when clean and clear of muck, now it will have a realistic sweep as well. Jack Edited November 7, 2009 by Jack1024 Quote Link to comment Share on other sites More sharing options...
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