RWG Technical

Now that's not fair... You know I love a challenge, and especially when it includes a very old movement in need of servicing - which this V72 needed desperatly. The movement was a bit of a mess, dirty, a bit corroded, and way out of adjustment, many hours later, it's working good considering the age. I was very pleased with the results, I just wish they could get these V72 hands made correctly, they all need broaching to get them to fit correctly, what a pain. But the end results speak for themselves. RG

No, I never said anything about being interchangeable. I was only responding to to your request for tips. I doubt that they are interchangeable at all (the balance and c0ck that is), I tried this one time, and 2 hours later, and every combination you can think of...I gave up...they are no where near the same movements. I think your going to waste your time with the balance and c0ck assembly. The rest is probably interchangeable but no guarantee either... RG

I never said they were faulty, I said they were not serviced correctly. Faulty implies a design or unfixable problem, not serviced correctly means the basic design is sound, it just needs to be serviced that's all. Normal human nature is to complain when you have a problem. I would guess for every one complaint we read about the Asian 7750 (this one included) there are many more Asian 7750's that are working just fine, without any servicing or anything else. And there as many that keep on working year after year without any servicing whatsoever. Eventually all movements need to be serviced, the Asian ones sometimes need it sooner than others...that's all... Any rep can be a "Red Flag", consider that the ETA's are all surplus, which doesn't guarantee anything in terms of servicing or age. If you want a trouble free watch, then quartz is the way to go. Mechanical movements require care, there is no way around this. I don't recommend purchasing anything, all I can offer is my feedback from my hands on experience with these Asian 7750's. This experience allows me to inform the community of what I see when I open them up. I can assure you that if the Asian 7750 was as bad as some would like us to believe, I would not offer to service them, and guarantee my workmanship for 6 months. I have not had a Asian 7750 returned to me due to problems after I serviced it for a long long time, only 1 return in the past 3 years that I can think of. I just serviced a Rolex 1570, which when it arrived was not running at all. Now it runs perfect. Should I tell everyone to stay away from genuine Rolex's because this one arrived not running? RG

I don't know, keep in mind that many members have 7750's that work fine without any servicing. Ask the dealers who sell the watches, they are the ones producing them. Yes it is, but it doesn't change the facts. That's fine for you, many members want and buy watches with the 7750 powering it. Every movement needs to be serviced at some point, no matter the make. Even genuine ETA Swiss movements need to be serviced, just like the one I did yesterday. Of course it's cheaper to replace a cheap 21J with a new one for less than servicing a 7750 would cost. Servicing a chrono is very time consuming and complex, it's like comparing an overhaul on a lawnmower engine, to a V12 Ferrari engine, both are engines but there is a huge difference in complexity. It's obvious you don't like the A7750, that's fine, many others do and have good success with them. My 3 year old 188 with the old A7750 still works perfect. RG

Wear them well. RG

If you have not done any movement work, I don't recommend you try removing and installing the balance c0ck from one movemenet to another. Your chances of success are not good. RG

It is still a mystery. I have at least 4 of them torn down as spare parts, and 2 more assembled. I have yet to figure out what it is, certainly nothing I can point to in the Bestfit manual... RG

Any un-serviced movement could be problematic, and the Asian 7750 as delivered is unserviced. It is probably completely dry throughout the motion works, has no oil in the balance cap jewels, is not adjusted correctly, and most likely is over oiled around the mainspring area. I see this all the time. The Asian 7750 once serviced, (cleaned, oiled, adjusted) runs just as well as the Swiss does. Don't think for a minute that just because you have an ETA Swiss 7750, your problems are solved. A perfect example occured yesterday, a Swiss ETA 7750 25 jewel shows up at my bench because it's not working right. I serviced it, and now it runs fine. The problem your having is not due to the origin of the movement, but due to lack of correct maintenance. The Asian 7750's are fine movements once given the same care and attention that a Swiss model has leaving the factory. RG

There is a section under the RWiki that deals with these questions and more. RG

The HE valve cover is attached with a screw on the inside of the case. It could be that the HE screw fell out (since it's not attached to the valve anymore) and got jammed up in the movement. Or, more likely the movement is contaminated from dirt and stuff getting sucked in via the missing HE cover. Everytime you wear a watch it warms up, when you put it down it cools off. Hot and cold acts like a vaccum on an unsealed case and sucks in impurities and crap, which in turn gets into the movement and finally it grinds to a halt... But even worse is that while flying the pressure went from ground level to 8000 feet and then back to ground level. This pressure change will cause the case to suck in anything loose from your carry on bag, which is probably why it quit when you landed. Next time your at altitude, open a plastic bottle of water and seal it up again, and when your back on the ground, note how it's caved in on the sides...this is what the watch would have experienced. It's probably going to need a full teardown and cleaning to get it going again. Josh has nothing to do with the missing HE cover, this is a common problem and easily corrected by gluing the cover in place. RG

Correct. I have removed the crystals for members and send them off for AR coating, but I only do this for Chieftang who is in the USA. RG

Probably got the hairspring to unstick by manipulating it. There is little that is magnetic on these movements, certainly the springs are non magnetic... If the problem comes back, you sould get the balance immersed in "One Dip" as this will remove any trace of oil and ensure the spring does not do this again. RG

It's great that you got it taken care of. The only problem is that these hairsprings are non-magnetic... RG

That is your answer. The sloted screw the hairspring passes THROUGH is the regulator. Cementing it to the spring, will not allow regulating of the watch... You already know the answer to this one. A 6497 is very common and should be known to any watchmaker. If you went to a mechanic and asked if he knew anything about a V-8 engine, and he said "What's a V-8" what would you do? RG

The question was about USA customs, not Canada customs. RG

Pictures are extremely deceiving and misleading when it comes to lume colour. I can lume a dial in C3, and if it's a black dial, all the white balance adjustments etc in the world will never show it to look like C3, it will look C1 white. I think this picture is misleading. Which is why the only real way to know the true colour, is to have someone who can look at a gen with their eyes let us know. Other than the 183 Blackseal which is white lume, all the others are C3 (from my understanding). RG

Balance hairspring coils touching each other, or the balance c0ck. Most likely due to oil on the hairspring. RG

Sounds like you figured it out. For reference, the lever is supposed to be out from the movement that little bit, which is why the spacer ring, or in your instance the case, can be the cause of the problem. Great job. RG

There are a number of reasons this happens. 1. Isolate the problem by first taking the movement out of the case, and monitoring it. If the 12 hour doesnt' move with the chrono off when the movement is out of the case - you have a pusher issue, it's touching the lever and disengaging the brake arm. 2. If you have a movement spacer ring (doubtful on a Daytona), and the hand moves out of the case, remove the ring, in case it's pressing on the lever. 3. If the hand moves when the movement is out of the case, you have to take the dial and hands off, and the top bridge off to try and find out why. It could be a defective chrono reset arm, or the plastic brake lever, or too much friction on the 12 hour wheel clutch etc... My guess is No 1 is the most likely. Hope this helps. RG

That doesn't sound right at all. You have to wonder how you could miss so much dirt and lint, but even more so - what happened to the cannon pin? I think your being mislead, missing a speck of dirt on the dial happens, but missing a whole cannon pin, that's another story. Re-seating the hands is not going to make the cannon pin longer, the hands are unmodified and the cannon pin is too short. If this was advertised with these parts installed, and we can clearly see that they aren't, then that is being deceitful and not a good thing for the members here. I would take offshore's suggsestion. RG

Your only option is to either replace the bridge, or buy a broken screw removal tool, it looks like a "C" clamp and allows you to get broken screws out of plates and bridges. RG

I would not say the Asian one is not reliable, it's just not compatible with the Swiss parts. But most of the models supplied now seem to be quazi ETA quazi Asian anyway, so I am not sure where the line is anymore. RG

I have re-seized one and the only way to do it is by unbending the links, and rebending them in place. Impossible to not have it leave a small impression, once you bend the metal in the other direction, it's hard to make it look like it did when it was made on a machine. RG

Ok, here

We'll know tonight, in about 10 hours, after I tear it down and have a look. Gunk doesn't happen overnight, it takes a number of years. This could be a compilation of parts from the surplus market, that is not unheard of... RG