RWG Technical

Fantastic post, well done, well written, clear and detailed, and thought out to consider all the problems. The only thing that makes me nervous is clamping the watch in the vise with the crystal still attached...especailly on the Tropic ones, easy to damage... I am so glad you posted this, this is by far the best How-To for drilling lug holes that we have had, detailed, considers the fact that alignment is critical, shows step by step what to do in clear english, and shows how to overcome all these problems, and do it the right way. Simply putting the case in a vise without considering the issues you raise, is not the way to do this job. Thank you for taking the time to do such a detailed post. Well done Bill, excellent job. Should be pinned as a How-To Drill Lug holes. RG

If you can get it looked at and fixed locally, that is your best option... I am always concerned about watches going back to the seller, as it could get taken by customs, and I think (?) your responsible if it gets confiscated... Time, money, and risk, I would opt for a local solution, or at least one in the UK, not the far east... Once I get a watch, I never send it back, no matter what... RG

Ok. It seems as if the Top pusher arm is too short, and not turning the chrono cam the required amount... On some of these models, I have seen a case clamp glued to the chrono arm to take up the slack from too short a chrono pusher... There is little you can do, except maybe exchange the watch or have someone look at it for you... RG

I would return it to the seller, or have someone look at it for you. The problem you describe is not a "break in" issue, my guess is that there is a problem with the pushers or the chrono cam. Try this, Press the top pusher until the chrono starts, describe what happens, you should feel a click as the chrono turns on... Once you confirm that the chrono is running, press it again (once only), and now press the bottom button, what happens? RG

You order all Omega crystals by case number...there are thousands of crystals, if you send them the case number, they will send you the crystal. A plastic crystal has to be replaced with a plastic crystal...due to the way the crystal is retained to the case. If your looking for a replacement other than an Omega one, then you measure the diameter of the case where the crystal sits (not the crystal itself) and from this measurement you add 0.50mm and order a plastic crystal this diameter. This is the correct sizing for retaining a compression crystal. If you can't get a genuine crystal from Ofrei, let me know on PM, I have a good supplier and may be able to find one. I would recommend genuine Omega crystal vs an aftermarket one... RG

With a sharp drill bit, you can avoid some of that bunching up of the metal around the outside of the hole... Normally I use one drill per hole, and throw them out after one use, that's how fast they get dull... What I do in your situation, is take my flat Swiss needle file, and file off the metal until the area is nice and flat and smooth. You can take a larger drill and countersink the hole a bit after you use the file, in this example, I only used a file on the outside, no countersinking was done. For polishing I use the Dremel with a round felt pad, and I use Metal Polish that is made for motorcyle or car aluminum and stainless wheels, it's got good bite and will polish up the rough stuff quickly...for the final buffing I use a cotton wheel in my bench grinder, and buff it up... RG

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Excellent, if you need the longer cannon pin and hour wheel, I keep them in stock. RG

The reason your hands are at an angle is due to too short cannon and hour wheels... See this post PAM cannon pin For more tech info, see here... http://www.rwg.cc/members/index.php?showforum=75 RG

Look at the balance wheel and hairspring with your loupe...note the arm that the hairspring is attached to - that's the stud arm, you don't want to move it. Look at the other arm, it's got the hairspring running through it and two small arms that stick out from the bottom, this is the regulator arm, towards the stud is slower running, towards the other way is faster running... It looks as if the arm with the blue dot is the stud arm. RG

I spoke up too soon...after I posted, I thought that this was the new model with no regulator arm or pins... And sure enough, that's exactly what it is, adjusting this one requires specialized tooling and training, both of which I dont' have... With any of these new free sprung balances, your much better off at a Omega service center, they have the training and tooling... $280 for a service on this movement is actually a good price given the complexity and tooling needed to do the work... RG

I have never seen one, but then again, I never tried to order one... The 7750 series movements stems are available in 10 and 6 sizes, even though the ETA tech sheets only list Tap 6 sizes... I have 7750 stems in stock with 1.2mm and 0.90mm threads... RG

Ok on the further info... Excellent price, congrats. Given that it's running slow and not fast, I would not think it needs anything but a simple adjustment. Any competent watchmaker (COMPETENT being the key word) can do this for you... CAUTION, be aware that there are many idiots who claim to be watchmakers, but have no clue...typically these inhabit shopping malls etc... I have gotten watches in for service, that the seconds hand was 75% of the original length...because the "Watchmaker??" cut the hand down, to make the watch run faster... I suggest you find a real watchmaker in your local area, and have him adjust the watch. That movement should be easily within a few seconds per day.... The fine regulator will not allow 45 seconds of adjustment, the regulator arm needs to be moved. If you can't find anyone to help you locally, let me know on PM if I can help you...I can adjust and send back the same day... RG

Typically a watch needing service, will run faster - not slower. Given that you don't know the exact age of the watch, or it's service history, it's probably best to have it fully serviced. It strikes me as odd that a Genuine Coaxial movement would be off in the negative direction by so much, this is a high end movement and should be very accurate. Did you have a Jeweller open the case and verify that it was a genuine movement in the case before you bought it?? Certainly most watchmakers can adjust the watch with a timing machine. COSC specs is another thing all together and requires the skills of a watchtimer specialist, there are few people around today with those skills... RG

I just got some parts in to repair the watch in question, and have finished drilling and polishing the lug holes, and other work that Arthur wanted done. I expect to have it done tonight or tomorrow, and will post some pics so you can see the end results. I think it looks good... RG

Amazing and beautiful job as usual... This is so well done, that any watch magazine would love to have such a great piece to print...well done. Thanks for all your time and effort in doing this up, now I will go and read it (I print and save them for reference). RG

I did not physically install one, but I measured a Swiss 7750 datewheel, and the New Asian one, and they were the same I/D and O/D...and the teeth matched up. Should work... RG

Your going to need a machinest or a machine shop to be able to do work like this... Enlarging existing holes is hard enough, taking an existing one, and making it larger by repositioning the hole will require some serious tooling...certainly more than a Dremel and cobalt drill bit... Anyone a machinest that dares take this on?? RG

Your welcome... Now I know how to install a V23 in my own 6263. RG

Ruined is right...I hardly detected the lume at all (yea, right)...what a mess... RG

Tons of information and tutorials here... Information link... You should not be able to press the crystal out with your fingers. The crystal is too small for the case. RG

It takes hours to do up even a simple post with pictures... I have done up numerous posts with just about every procedure explained in detail and living colour... Have a look here, uncasing a movement is basically the same on all watches, there are numerous detailed posts about uncasing just about everything...a 7750 is not much different. Uncasing and just about everything else technical... RG

Fantastic results...great stuff that you did it yourself... RG

No not really... It's a crap shoot at best...just when they get something right, they screw up another... Case in point, first few NEW Asian 7750's had excellent cannon pinons (unlike the older ones that ALL needed re-working by me to get them to work), but the latest ones are crap...good news is I can replace them with Genuine ETA parts... And each and every new Asian model lately looks like this on the inside... At least there is consistancy...they are all over oiled and full of crap... RG

For what it's worth... I have overhauled more 7750's that I want to remember (new and old Asian models), and so far the number of them that have been returned for warranty repair due to failure is ZERO... So they do seem to work fine after servicing, my older Asian version is going on 2 years of constant use (chrono and all...) and it's still working fine... RG