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Yes, that screw is real.

Tighten it (and the other rider tab screws...just in case) and you'll be fine.

The screws that hold the bezel in place (on the Gen) are, on the Replica, fake. Turning them won't do anything.

Beautiful watch. Do you know if it was difficult to remove the crystal (for AR coating)?

Well, this is an eye-opener. I never noticed that the layout of this particular movement was different from the others.

So, this means that there are at least 3 distinctly different (not all parts are interchangeable) A7750 versions (are there more?).

- Low beat (21,000bpm) A7750

- High beat (28,800bpm) A7750

- Daytona Seconds-at-6 A7750

This may explain why, even though I've replaced parts in my daytona movement (with parts from a High bt A7750), it's not working (the escape wheel won't engage properly).

Thanks for the info.

Obsessed? Oh yes, I'm obsessed!

Have you checked Cousins UK?

http://www.cousinsuk.com/

If you have the ability to do this, why don't you consider doing a tricompax Navitimer datewheel?

It's an expensive and labor intensive process to make datewheels. When I finished my BCE datewheels, many of the people who had expressed interest, suddenly vanished (lesson: take the money up front). I certainly have the ability to make Navitimer datewheels, but I honestly just don't have the time or money for such a project (and I don't want to spend a bunch of time and money just to be sitting on a stack of datewheels...again).

If I can do it, anyone can. It just takes money and a lot of persistence.

No sarcasms at all...I was just hoping that you will share or try to developp a new AR servicing for us...

Oh, good!

I'm sending more crystals out this week. I'm including more of my own as well as a few from some friends. I'm keeping it very limited for now. I want to know what my friends think of the coating before I offer it to anyone else. I will, of course, have to go through the proper channels if I want to offer an AR service to the community.

I definitely don't want to negatively effect Chief's business. He does a great job and I don't want to do anything to make him want to stop.

Just tongue in cheek from me....I have no doubt your specs are decent enough

No problem. For once, I actually understood the humor

I just though I'd throw in the information on the specs in case anyone wanted to know more about them.

me too.....but "military standard" is sort of vague

...Kind-of like Military Intelligence.

But actually, the Mil-Specs for this coating aren't too bad. You can look them up here: https://assist.daps.dla.mil/online/start/

Just hit the 'QUICK SEARCH' button (on the left of the screen) and type in the number of the Mil-Spec (from my original post) in the 'Document Number' field.

Even if I was willing to 'give' away my information, it would be complicated. I designed and fabricated special holding fixtures and came up with a specific process to get the correct color. I'd have to generate drawings and document the process. In addition, it took time to develop a relationship with my supplier (I've been through several suppliers). These are things I'm not willing to just give away (not yet anyway).

I may offer to coat crystals for other members, but I need to make sure that it doesn't violate any forum rules. In addition, I don't want to step on Chief's toes.

+1

I don't understand, are you being sarcastic?

Who's your secret!????

It took a lot of work, money and persistence. I learned more than I thought I ever would about AR coatings. It took me over a year of effort and because of that, I'd prefer to keep my 'secrets' to myself for now .

In an attempt to achieve a Gen-like AR coating (and not being able to get in on one of Chief's runs), over the last year I've contacted various coating houses to find a coating (and process) that would give me acceptable results (not easy). I've had crystals coated twice before but had limited success: http://www.repgeek.com/showthread.php?p=1460069#post1460069.

I received my latest crystals today (my 3rd attempt) and I must say that I think it looks amazing. Attached is a photo of my new crystal on top of the Gen. It's very slightly more violet than the Gen, but I think it knocks down reflection even better (and way better than a rep):

Here's another picture (mine is on the left):

the coating is applied per Military standards and meets or exceeds the following:

* Abrasion, Mil-C-675A

* Adhesion, Mil-M-13508C

* Hardness, Mil-M-13508C

...I'm VERY happy!

I've had my Quartz Porto for years and it's still running strong. It looks nice, functions well and I don't have to worry about breaking or loosing it (it's my 'take on vacation' watch).

The quartz version is an inexpensive way to see if you like this watch. You may eventually decide to move up to an automatic...or even a gen.

It's very generous of you to offer your services. With those tools, it would seem that you could make some awesome dials!

It sounds like you used the 14 micron, but did you go through the entire process and work your way down to the 1/2 micron paste?

From what I've read, the 1/2 micron shouldn't leave hairline scratches (but requires a lot of work). I am about to order some from McMaster carr (I have a screwed up BCE crystal).

That looks odd. Certainly nothing like I've ever seen in a 7750 (although I'm not the expert).

I have a spare spring (the one you need). PM me with your address if you want it.

At first glance, I thought it was a Hamilton. Upon closer inspection...nope...at least, not this one.

Can you post a picture of the back of the watch?

Is this quartz by any chance (not important...just curious)?

The best value is to install a genuine Miyota 8215 in place of the asian copy. 99% of the time the Miyota is compatible with the existing 21J.

I did not know that...good information, thanks zig.

It would probably cost more to have it repaired that to purchase a new movement (unless the problem is VERY easy to fix).

The piece you're talking about (on all of my clasps), is a pressed together piece (no screws). I think it's called a pressure bar (at Cousins UK: http://www.cousinsuk.com/catalog/10/0/1998/4049.aspx#select) or a rivet pin (Ofrei: http://www.ofrei.com/page478.html).

What, exactly, broke (a picture would be useful)? Depending on what it is, it might not be too difficult to repair.

This is great information. I've used the .pdf files extensively to locate part numbers and for laying out my own Breitling Datewheel.

Thanks Dr.

What movements are in the watches you purchased?

I'd love to see pictures.