Toadtorrent Posted November 12, 2008 Report Share Posted November 12, 2008 Ok...everybody gets a Noob Question allowance right? I've expired mine long ago...so I'm going to call this a plea for "confirmation" instead. I've been getting a few "clarification" questions from folks about movements to which I know little about, and wanted to confirm if my understanding is correct: 7750a/b = the old 21k slow beat 7750 that is seen as a bit unreliable7750a/b still available and listed as the slow beat movement (preferred for modding due to gen ETA sized hand compatibility )7750b1 = New Asian 7750 = 28.8k A7750...our The Zigmeister approved workhorse (once serviced)Does this sound right or is there another version (aside from the gen and subdial layout variants)?? Quote Link to comment Share on other sites More sharing options...
Krayfish Posted November 13, 2008 Report Share Posted November 13, 2008 Glad your doing this because this 7750 is pretty confusing to me also. Quote Link to comment Share on other sites More sharing options...
RWG Technical Posted November 13, 2008 Report Share Posted November 13, 2008 As far as I know, there are two main variants of the A7750. Variant #1 is the slower beat 21.6K version. This version has the same sized chrono hands as an ETA 7750. Variant #2 is the faster beat 28.8k version. The majority of these versions have chrono hands that don't match the ETA 7750, normally all the subdial and center seconds hands are 0.20mm size. The sub variants designated by the various letters are (if I remember correctly) a brain child of Eddie Lee...my response when the different letters were starting to be used was "B1, B2, BS..." it's meaningless. Some clarification on the serviceability of each variant. The older 21.6 K version did suffer from dirt and lack of proper servicing, but the new 28.8K version is overall in worse condition than what it replaced. While the 21.6 K version was dry and dirty, a good cleaning and oiling and it was out the door. The newer 28.8 K model however is prone to be soaking in oil in and around the mainspring barrel, it has a number of manufacturing defects, almost all of them have defective escapements and require a lot of time to get adjusted and working correctly. Many times I can't get the pallet adjusted correctly and have to replace it with a spare I have. So while the newer version does look better and is finished better, the tooling it's made on is defective and each and every one coming off the line has problems that need to be fixed. I just wish they would fix the problems at the source so I don't have to spend hours adjusting and correcting the induced defects. RG Quote Link to comment Share on other sites More sharing options...
Toadtorrent Posted November 13, 2008 Author Report Share Posted November 13, 2008 The sub variants designated by the various letters are (if I remember correctly) a brain child of Eddie Lee...my response when the different letters were starting to be used was "B1, B2, BS..." it's meaningless. Thanks so much for this The Zigmeister...pulling through with the Master's knowledge like always!! I've been seeing the B1 designation being used every now and then on the collector sites...so I guess it still begs the question with the collector's on what the heck they're sticking in there...either slow beat or high beat seem to be the answers we're looking for. I was thinking of buying spare A7750 movements to keep on hand for when you service my movements in case you needed parts...but now I'm not sure if that's a good idea if the parts in the current movements are defective and need replacing themselves. Are there any options that are reasonable to consider (given you've found ETA parts are a real crap shoot to fit in if they can be at all) or should we just do a rip and replace with a new movement and pray?? I found a decent price on ETA Valjoux 7750's...but I think I need to buy about 100 of them. Quote Link to comment Share on other sites More sharing options...
RWG Technical Posted November 13, 2008 Report Share Posted November 13, 2008 I forgot to add, that of the new 28.8 K versions, I have seen at least 6-10 sub variants, meaning that they are all 28.8 K models, but there are subtle but significant manufacturing differences between many models, including the hand sizes of the chrono posts, some with fine regulators, some without, etc... Just when you think you have it figured out, it changes, again... From what I have seen, during the past 2 years, all of the A7750's being sold in our reps are the newer 28.8K model. If they want to call it "B1" that's ok, but it's really meaningless from a consumer point of view, maybe the manufacturer's call it this for some reason. I do have a lot of spare parts, the problem is the common ones (winding transfer gear, reversing wheel) are all used up and the ETA one's don't fit the A7750. Having said that, I did buy a winding transfer gear, and managed to turn down the pivots on the lathe so it would fit the Asian model, but if you add the cost of the part ($25) plus the time to modify it to fit ($25), it's getting very expensive to repair. The ETA pallet won't fit and can't be made to fit, so I have no choice but to correct the manufacturing defects, keep in mind were talking 1/100 mm adjustments here...very tedious. As for options, the good news is that I have figured out and can correct and get running the current A7750's. I am not always 100% successful and do have a few returns now and then, but the problems are always due to existing defects, not the work I did or didn't do. And sometimes no matter what you do, you get a defective movement that you just can't get to work right... For a standard 12-9-6 layout, replacing the A7750 with an ETA is good value, but only if your planning on keeping the watch. The cost of the ETA is very high, and add to that the installation cost, and the cost of servicing, and your well into $700 or more. I say servicing since many of the ETA7750's sold are surplus movements and need servicing to get them working. Best value for the money (my OPINION only) is to service the Asian 7750 within a year or so. And on any dial layout other than the standard 7750, it's your only option. I can count on one hand the number of A7750's that have been sent back for warranty work over the past 24 months...that tells me a lot about the reliability following servicing. RG Quote Link to comment Share on other sites More sharing options...
Toadtorrent Posted November 13, 2008 Author Report Share Posted November 13, 2008 I forgot to add, that of the new 28.8 K versions, I have seen at least 6-10 sub variants, meaning that they are all 28.8 K models, but there are subtle but significant manufacturing differences between many models, including the hand sizes of the chrono posts, some with fine regulators, some without, etc... Just when you think you have it figured out, it changes, again... ...I can count on one hand the number of A7750's that have been sent back for warranty work over the past 24 months...that tells me a lot about the reliability following servicing. No wonder we're confused on this one. 6-10 variants? That must mean the factory has 6-10 different shifts of workers. We know about your success rate-post-service...so that is good to know that even with the differences and issues...there's a good probability of "life". Thanks for the insight!! Quote Link to comment Share on other sites More sharing options...
milsub5517 Posted November 15, 2008 Report Share Posted November 15, 2008 The Zigmeister, how is the quality of these new seconds at 12 asian 7750's? i really want to buy AP with this new movement but somewhat worried.. thank you. Quote Link to comment Share on other sites More sharing options...
RWG Technical Posted November 15, 2008 Report Share Posted November 15, 2008 ziggy, how is the quality of these new seconds at 12 asian 7750's? i really want to buy AP with this new movement but somewhat worried.. thank you. I think I did a servicing on one of these not too long ago, before my France trip...but I can't remember for sure. I believe it was the same quality as the seconds at 3, meaning that it was fully jewelled and worked ok. So far the owner hasn't returned it for warranty so I guess it's still working. RG Quote Link to comment Share on other sites More sharing options...
relox Posted February 7, 2009 Report Share Posted February 7, 2009 Hi, The Zigmeister (and Co.) This is Relox, from Spain. I would like to ask a question regarding asian movements. I am interested in a PO 42 mm which Narika (Reg), who is currently abroad, will be likely able to provide. It Quote Link to comment Share on other sites More sharing options...
Toadtorrent Posted February 7, 2009 Author Report Share Posted February 7, 2009 This is Relox, from Spain. I would like to ask a question regarding asian movements. I am interested in a PO 42 mm which Narika (Reg), who is currently abroad, will be likely able to provide. It Quote Link to comment Share on other sites More sharing options...
relox Posted February 7, 2009 Report Share Posted February 7, 2009 Crap...my longer answer got nuked somehow...so you're getting a second try condensed one. The movement is likely a DG2813...the most popular rep movement around and is the standard "Asian 21j". The movement itself can be had in Toronto for $10 CDN...the rest of the world about $12-15 USD + shipping. A movement swap costs $50 or so from a watchsmith and any of them can do it if you supply the movement...or they might actually have them. It's not worth servicing the movement (costs way more than a swap, no spare parts are available and The Zigmeister has said servicing these is a lesson in frustration)...just let it die...and replace it. The datewheel will have to be saved (or overlay). Look at the Ajoesmith tutorial redux in my signature for details on how to do this. Thanks, Toadtorrent. Now I got it! I am a noob, you know... :-) See you, Quote Link to comment Share on other sites More sharing options...
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