RWG Technical

Even with the proper tool in a vise, the caseback was so tight that the whole table and vise were moving, I had to have my son hold the vise down and it still wouldn't break free. No slippage at all and no risk of slippage, just a damn tight caseback. I broke my LG caseback wrench on a really tight PAM caseback, meaning the handle on the LG broke in two pieces...and I have broken some of the bits on the LG as well trying to open really tight cases... Freezing shrinks the caseback just enough to allow it to be opened. Only the caseback is frozen, not the rest of the case. You need a difference between expansion rates of one and the other for it to work. RG

The "MYTH" or Misconception that a Asian 7750 21.6K slow beat model is "crappy" is just that - a misconception and incorrect. I say this from hands on experience with the actual movements. Both the 21.6k and 28.8k Asian 7750's have problems and issues as delivered. What was a weak point on the 21.6k model has been corrected on the 28.8k movement, but what was a strong point on the 21.6k model - has become a weak one on the 28.8k model. So they both have flaws, but one is considered "good" and the other "crap"?? The older 21.6k Asian 7750 got a bad rap and continues to have this bad rap, quite undeservingly I think. I have a 3 year old 188, it has a 21.6k A7750 in it, it's been worn often and stored on a winder when not in use. It has continued to work perfect for the past 3 years, keeps as good timing as my ETA or Tudor 7750's when on the winder. The Asian 7750 that is shown in the high end model with the engravings for $1000, is nothing new or special. I have seen these for a number of months now, and they, like all Asian 7750's have problems. The fancy engraving doesn't fix the design flaws and weak points. Not one A7750 I have taken apart was serviced correctly or didn't have something I had to fix or repair to ensure long term reliability for the customer. That doesnt' mean that I dont' get the odd A7750 sent back to me for warranty, all the servicing in the world is not going to fix design or parts quality issues. RG

Glad you like the workmanship and results. Wear it well. RG

Looks great, and it is big to say the least. @ Kruzer, I ain't going near that one, or dare say anything that could cause me physical distress RG

Send me a pm with your address, and I'll put the parts in the mail for you this week... RG

It looks great, I didn't know it was a gen, having never seen this model, I though it to be a rep...so much for my being able to tell them apart. Lume shot looks good, that's about how it looks after a minute or so anyway, better to be honest than have a 2 minute exposure that distorts reality. Wear it well. RG

Glad to hear, as per normal, if the results are not exactly what your looking for, I'll do what is needed to make it to your liking. RG

I got the caseback off, used the old freeze the caseback trick and it worked... Mods on the way... RG

Just to add on the markers and the thickness of them. I do this on a as requested and needed basis. If you don't ask for them to be cut down, I don't do it (because there is always a risk when removing them). If the markers are crooked or crumbling apart (some of the markers are like wet sand and break up as soon as you touch them) I will remove them and make new ones. It's not easy to make square sided markers, and the thickness is my best guess as to what looks good. As with any mods, I will try and duplicate or create what ever you want for the size and thickness of the markers. RG

Wow, I see I am not the only one to miss this great post...not sure how that happened. Great post thanks for taking the time to write it up, very informative. RG

You are very welcome as always. Wear it well. RG

I think the reason most people didn't comment (me included) is that 0.5mm is such a small issue. Reps are full of errors and mistakes and flaws, this small an error, all things considered, is quite acceptable to most of us. Typically the errors and flaws are much more glaring than 0.5 of a mm... RG

The biggest problems on the A7750, are sticky or defective reversing wheels for the autowinder, and loose cannon pinion gears which causes hand slippage. Not being serviced and being over or under oiled are the other issues, both of which I see on the non-chrono as well as chrono models. Certainly the non-chrono ones have less moving parts to go wrong, but as above still can have the common problems of the A7750. RG

Unless you specified a warranty against defects for X number of days, then I don't think you have any responsibility for the watch quitting. How's this sound... I buy this watch, after a week or so, I get buyer's remorse...hmmmm...what to do... BANG...oops I smashed the watch on the table, and wouldn't you know it, it doesn't run anymore...HEY SELLER- give me my money back!!! OR I accidently drop the watch, it stops working...what am I to do...let's see if I can get a refund...hey you sold me a broken watch. Send the watch to me, I'll have a look and let you know what is wrong, and if it's damaged, you can warn others not to deal with this particular individual. If you had the watch for a while and it worked fine, the owner had it for 8 days without any issue, and it suddenly stopped working, it's somehow your fault? Not in my books... RG

Not at all, I will walk you through it so it will go together without any problem... RG

Overall the movement averages out, after servicing if you check and adjust the watch on the timer, it's normal to aim for +6 to 10 seconds per day. For the average user, this tends to even out the rate while being worn. Position errors are a result of the design of the movement and the quality of the parts, which is why the genuine Rollie's are clearly marked "Adjusted for temperature and 5 positions". Were not so lucky, our movements don't have anywhere near the quality or design. The only real way to get an accurate mechanical watch, is to have the wearer use the watch for a day, then measure the error and correct it. For example, if you wore the watch for 24 hours, and at the end of the test, the watch was +20 seconds, you would put it on the timer and adjust it - 20 seconds to remove the error. Also keep in mind that as a watch unwinds, it speeds up, adding to the problem... Anything in the + - 20 seconds per day for an ETA and I'm happy...more of an allowance for the Asian models. RG

Understood... Then the fix is to have a watchsmith or yourself (if you're capable) look at the watch and find out what the problem is, and fix it. RG

A correctly serviced movement wont' bed in like a car engine will that's new. The reason is that once it's oiled correctly, there is nothing to wear out or bed in against. The timing of any mechanical watch will vary as it's being worn. There is always positional errors, dial up and down typically run slower than crown down (side load on the pivots). On an unserviced movement, or one that is over oiled, the friction varies quite a bit between positions, and the timing will also vary. What you see is quite normal, and even once serviced you will see variations in the timing, a 7750 that is serviced typically is withing a few seconds on the timer in all the positions. But even so, while being worn, and the activity that the watch is put under (sitting still, leaning on your writs, walking etc), can cause the rate to vary 30 or more seconds per day. RG

Just to confirm, your winding it fully until you can't possibly wind or turn the crown anymore? If the answer is "yes", then the mainspring can't be broken, or it would never stop winding. If it's keeping good time, it sounds as if the movement is ok, but it could be as simple as the hour hand touching the dial face, I have seen this a lot on some watches from certain modder/dealers, this adds resistance which can stop the watch from running down completely. Or there could be another problem, maybe a dirty movement, but normally a dirty movement runs fast, not only for a few hours. My guess, is a hand touching something...or the case clamps installed incorrectly (have seen this a lot as well) and putting to much pressure on the movement jamming it up. Also note how many turns of the crown are needed for a full wind, compare this to your other hand winds...same amount of turns to wind, or only a few turns before it stops winding...more info will help... RG

Great tutorial and post. As for letting down the mainspring, unless you remove the pallet arm, there is no reason to let the mainspring down. Removing the balance can be done with the mainspring fully wound up. Only if you take the pallet out, does the escape wheel become free to spin and then you need the mainspring unwound. RG

If you can remove the winding bridge with the click wheels, I can clean them up and send it back to you (rotor off, then take the two black screws out and the bridge comes right off). Let me know on email if you want to do this... RG

Wow, great post and wonderful pictures and text, well done, easy to read and very informative. Congrats on such a fine piece from Kruzer's collection. Wear it well. RG

It was a pleasure being able to help you out. The watch looks good, wear it well. RG

Click wheels are gummed up, a bath in the Ultrasonic machine with L&R cleaner, followed by a long soaking in One Dip will normally fix the stickyness and free them up. I have been using this process for a while now, and it has been working great on the 2836 (24) and also the 7750 reversing wheels. RG

Sounds good, hopefully you didn't pay $50 for each level to Ofrei and instead bought the course CD from Offshore (I supplied the TZ course info and the ETA 7750 factory course to Offshore for his CD). RG