Rolexman

Just 2 weeks ago I tried to buy a Navi SS with Andrew and upon receiving QC pics I noticed it had the 'regular' Navi case back. After emailing him my observation he contacted the factory which told him the SS case back is out of production since 2 years..... So I changed my order.

Apparently these Navi SS are out of production, or at least the case back is.

Well, I respect the skills of the various modders on the forum, but what he is telling you is impossible. The 7750 and 7753 have virtually the same dimensions. The 7750 that is in the 3-6-9 tricompax Navi has an extra bridge to raise the transfer gears over top of the datewheel. This is what causes the recessed date. The case on the models has the hole for the stem moved towards the back of the case to accommodate this modification. When you put a 7753, or a 7750 for that matter, in the 3-6-9 case the stem will not align properly withh the crown tube. I don't care who your modder is, unless he can turn water in to wine, he wont fit a 7753 in to your case.

100% correct.

4m per hour can't be regulated with that arm. Something else is wrong. How does the balance swing look.. long swings or fast short swings. Post a vid if you can.

You changed the crown?.... looks thinner. IMO kinda weird looking.

The gap never bothered me so I can't understand all the fuss about it. Adding gaskets and other modifications will eventually influence water tightness in a negative way. I WPed my 177 to 5 bar in a original state without a problem

Waiting since 16th december 2010!!!!!!!!!!!!!!!!!

Didn't get mine either... Ordered the day after it came out. Got shipped the 16th.

thanks great info!

gen or rep?

Rep off course

I stand corrected. You guys are right about the flaws..... but it's such a damn cool and versatile watch to wear

About the crystal, it seems to be much more "dull" than average rep crystal, also the AR is awful. I replaced it with the OEM spec crystal from Bigcrown. Wished I took the picture to show the difference.

The CG, the lever sticking out too far. Known issue on all of the new 111J. The CG on the 177L is much better.

Yes, we all want perfect rep, but that would never happened. I have never found any "conflicting" with personalized my watches. In fact, all of my watches were modded to be different than the genuine because I know I cannot achieve 1:1 replication of the genuine piece.

Thanks, good info! The more posts I read the more I'm convinced the 177 is the best choice.

Update: I enountered two things that caused some problems. A balance cap leaked oil which contaminated the hair spring and thus making the coils stick. On the other movement it was the end-shake... The balance cocks could not be screwed down propperly because the balance would stop (ergo to much pressure on the staff. So I made a small 'pics ear' and voila. Both amplitude en timing problems solved!

I still didn't figure out the whole isochronisme, amplitude and rate relation and how they interact..

We all want a 'perfect' rep and than we just feel like luming the hands red!?....IMO rather confliting

Photo's uploaded again.

Wrist shot:

so why do you consider the crystal not to be good?

Very curious red-green watch!

Where do you consider the CG´s biggest flaw?

Would like to know too!

1. Major flaws are the dial finish (glossy, not matte) 2. Less significant are the crystal height (slightly too high)

1 and 2 both not true for the 2010 version. Gen has gloss dial and higher crystal hight than rep. I own the rep and I must say it is pretty damn accurate! Besides that I can't really tell what should be wrong with the shape of the case...

yes the watch will be changed to another one

He'll probably just fasten the screws

When did the dials change..???

Mine has "automatic" in red, and "200m/660ft"

Is this the 42 MM "mini version..??

Sharp eye!

Thanks very much! Great to hear your observations and motivation. Helps with making a decision!

My question stands. See #12

i would pick the 177L.. just feels more gen-like,

First of all thanks for sharing! Based on what would you say makes the 177 more gen-like? Judging form the pics I would say the 111 is the better choise. It has a better finished movement (gen like côtes, engraved OP, and right dagger) beter crown/ tube etc...

Your a "home-taught watchmaker"...well had I know that that it would have changed everything...that's the last time I help you out...snob...

I have one in my city as well, a SNOB watchmaker, but he prefers to call himself a "Horologist"...he's a dumbass and snob and knows squat about watches...his life is one of replacing watch batteries in quartz. I called once and asked him if he had a stem for an ETA 2671, and he had no clue what type of movement that was...other than to say it was such a low quality movement that he wouldn't even work on it, or have a stem that would fit...so much for being an expert...

To hell with the 'Horlogists'... home-taught rules

Checked the regulator pins and they are fine. Just some nice touch and release of the hair spring.

Looked in to the whole isochronisme and per definition it would mean that no matter what amplitude rating I would get, it will or should not affect the rate...

So if amplitude does not effect the rate what does? The lenght of the hair spring! And this is only altered by the regulator. So back to square one

These technical things just grind through my mind the entire day. I will find the answer eventually

Well the watch should run slowwer in crown down but that is a big change what is your beat error? do you have another vibrograph you can make comparisons with any where near you?

Beat error is perfect 0.1 and 0.3. Unfortunately no back up Vibrograph.. I'm on my own as no watchmaker in my neighbourhood likes home-taught watchmakers. The snobs! I do however was under the impression that crown down leads to a higher beat-rate (more friction on the balance staff ergo lower amplitude). At least all my 2836 movements act this way..

Yes and no, lower amplitude can mean shorter swings and a faster rate, but you are not considering the position of the regulator pins and the position of the hairspring when the movement is placed in different positions...that is more critical than the swing length, after all our balances and hairsprings are designed to have isochronosime between full wind and unwound.

So, lets say in the DU position the regulator pins are touching the hairspring all the time, and it's running +20 sec/day...

Now, you move to the CD position, the amplitude is supposed to lower, but at the same time, the hairspring is not touching the regulator pins because of gravity, or only partially touching the pins as the hairspring winds up and unwinds...what has happened? The effective length of the hairsping has increased, increased hairspring length = slower vibrations...

So it's possible, you have to look beyond the readings and check out the regulator, I suspect you will find your answers... (hint, use a 10X loupe and watch the regulator pins where the hairspring passes through it, look carefully in all positions to see what is happening).

Good luck.

Will check it out tomorrow. Thanks for chiming in Zig. Much appreciated!

Cool thread with a lot of usefull stuff!

I'm having some problems with my vibrograph (MTG) lately.... or it could be the watches I'm measuring?

What happens is (in this case both ETA 2892 and a 2671)

E.G.

-In the dial up position the amplitude is say 270 and the rate is +20 seconds fast

-In the crown down position the amplitude drops say to 255 (-15 degrees) but the rate also decreases to + 5 seconds fast

I can't find the logic. Lower amplitude means shorter balance swings which should lead to a higher rate?! No?

So either there's is something I'm missing or my MTG has to be recalibrated?

Would love to here some thoughts!