7750 chrono

Taken from a forum...

User guide to the 7750 automatic Chronograph movement

Pity the poor 7750, of all the movements, it has to be the one that is discussed the most on these forums, yet it’s probably the most misunderstood and certainly the one movement that everyone has an opinion on. There are so many myths and legends and un-truth’s about this movement, that I though I would share with you those that I remember.

Myth or Truth??

1. You should run the chrono for 24 hours after you first get your 7750, to help “distribute” the oils…

This is totally untrue, not only for a 7750, but for any watch movement. If you understand how a movement is oiled, where it’s oiled, and how the oil is applied, you will know that this is impossible. A movement doesn’t have oil “sitting around” waiting to be splashed and distributed inside the movement when it’s running. When speaking about lubrication in a movement, the type, quantity and how it works is not like any other mechanical thing. It’s certainly not like a car engine, or even the engine in your lawnmower.

In a properly lubricated and serviced movement the oil is held in place between the pivot and the jewel via capillary action. If the oil is held in place, then it has no where to go or be distributed to…

For a movement to be correctly oiled, it first needs to be perfectly clean and dry. Oiling any movement without a full teardown and starting with a clean and dry jewel and pivot, is another myth. Once you have a perfectly clean and dry movement, a measured drop of the specific type of oil is inserted into each jewel, between the jewel and pivot. The measured drop of oil then gets sucked in by capillary action, and the oil fills in the space between the jewel and the pivot. And there is sits, forever. Once the oil fills the space, it can’t move, or be distributed or anything, capillary action keeps it secured in place. The oil will stay there until the watch is cleaned or disassembled. Time only causes the oil to deteriorate and dry up and in about 5 years (makes no difference if the watch is running or not) the oil needs to be replaced with fresh oil.

Since all the oils that are used in lubricating a movement are held in place within the jewels by capillary action, what oil is exactly being “distributed” when you run your chono for 24 hours? The answer of course is “none”.

Myth – Busted

2. You should only run your chrono with a “Fully Charged or fully wound movement”.

The friction in a movement is carefully planned. There is a certain designed friction built into each and every movement. Part of that friction is of course the oil type and quantity applied in each pivot and jewel during servicing. If you over-oil, or under-oil, or use the incorrect type of oil when you service the movement, the running of the movement can be affected dramatically. Over oiling a movement can stop it running completely, under oiling can cause over-banking of the balance wheel (spinning to far and hitting the impulse jewel).

If the power reaching the balance wheel varies, the balance wheel will swing more or less (more power = larger swing, less power = smaller swing, less swing = faster, more swing = slower). If the balance swings more or less, the rate of the watch will vary, if it varies, the time keeping is not accurate.

Therefore the design of the 7750 chronograph, like any well designed movement, is such that the balance wheel can’t tell the difference between a running chrono, and a chrono that is stopped. If the basic movement friction doesn’t vary from chrono ON to chrono OFF, it makes no difference as to the state of wind of the movement when the chrono is engaged.
You can run the chrono at any time, whenever you want, it makes no difference as far as the movement is concerned.

Only two things happen when you start a 7750 chrono

1. The tilting pinion (which is running ALL the time) tilts over and engages into the center chrono seconds gear. The center seconds chrono gear has slight friction, in fact it’s very free to rotate, any friction would be the actual gears meshing. The only real friction is when the center seconds gear ticks over a “minute” on the 30 minute counter. If your movement is serviced correctly, and the chrono adjustments are all within the specifications, there would be about 2 seconds of actual engagement between the center seconds and 30 minute counter, this quick engagement and disengagement isn’t enough to slow down the balance wheel and affect the rate.
2. The 12 hour wheel wants to run all the time, why? well because it’s connected directly to the bottom of the mainspring barrel. As long as the watch is running, the mainspring barrel is spinning round and round. The reason the 12 hour counter doesn’t run when the chrono is OFF, is because a break lever is preventing it from running. Turning the chrono ON, releases this break lever and the gear starts to spin.

That’s it for what happens when you engage the chrono, very simple and easy.

So starting the chrono causes the tilting pinion to swing over engaging the center seconds gear, at the same time the 12 hour wheel is released and starts to spin.

What does the movement see? Nothing really, it doesn’t know if the chrono is ON, or OFF, because there is no change in the friction or running. So if the movement can’t tell if the chrono is running or shut off, what does it matter as to the state of wind of the actual watch? It doesn’t matter, you can engage and run the chrono any time you like, and even leave it running until the mainspring runs out of power…it doesn’t make any difference.

Myth - Busted

3. Don’t set the date between 7 pm and 2 am

This is true for all 7750’s, Asian or ETA. There are two type of calendar changeover gears, Instant, and Slow.

Instant Date Change. A small gear with either a built in moveable spring or a spring connected to it, changes the date “instantly” when it snaps over at midnight.

Slow Date Change. A fixed gear rotates along with the hour gear and slowly engages into and switches the datewheel. Since this gear has a fixed tab that engages into the Datewheel, if you try and change the date when this tab is engaged into the Datewheel, you will damage the Keyless works. It’s not a design defect, it’s just the way it is on this model, if you want a date function, the size of the movement only allows a certain type of date change gear, in the case of a 7750, a fixed gear is installed.

The date gear starts to engage with the date wheel around 7pm and disengages totally by 2 am, if you attempt to do a quick date change during the engagement, you will damage the watch.

Myth – Confirmed

4. The Rotor on my 7750 is noisy

The 7750 rotor only winds in one direction. The winding direction has resistance since the rotor is trying to wind the mainspring. In the other direction there is no resistance at all, and the rotor is free to spin around, and around…and around… If the rotor bearings are dry, there is nothing preventing the rotor from spinning like crazy. Lubricating the bearings helps to quiet the rotor and prevent such a free spin in the non-winding direction.

The noisy rotor is normal, it can be made quieter during servicing when it’s lubricated, or you can lubricate it without a full service.

Myth – Confirmed

5. Don’t re-set the chrono with the seconds hand anywhere but between 10 and 2 on the dial

On an un-serviced 7750, the reset hammer slams down very hard onto the heart cam’s for the Seconds and Minute counters. This force can and will cause the seconds hand to slip, if the hand is sitting anywhere but between 10 and 2. Even genuine watches can suffer from this problem. A slipping center seconds hand is totally preventable by the owner, all you have to do is never reset your chrono between anything but 10-2.
Myth – Confirmed

I think that’s about what I can remember, if you have any further items that you think should be added to this list, please let me know and I will address them.

And as always, all of this is based on my personal experience with these movements as well as standard knowledge with movements and their servicing.

Adam ve Kadin

ADAM- Sevgilim bugunlerde cikabilecek miyiz? Hayir hazirlanman birkac
yil daha surecekse bu kiyafetlerle cikmayalim.
KADIN- Neden?
ADAM- Moda degisecek hayatim... Ya da en azindan mevsim degisecek,
yazlik kiyafetlerle usumeyelim diyorum.
KADIN- Abartma.
ADAM- Sen de abartma. Bir bucuk saattir portmantonun aynasinda kendimi
seyrediyorum ve sikildim.
KADIN- Bir de benim durumumu dusun. Yillardir ayni manzarayi seyrediyorum.
ADAM- Ne varmis manzarada?
KADIN- Pek kayda deger bir sey yok. Bir burun ve arkadaslari.
ADAM- Cok komik... Kadinlarin siradan bir evden cikis hadisesini neden
bu kadar ciddiye aldigini anlamiyorum. Sanki bir daha donmeyecegiz.
Gidip bir evin bahcesinde kofte yiyecegiz, hepsi bu!
KADIN- Ona barbeku partisi deniyor canim.
ADAM- Oyle mi? Koftelerin bundan haberi var mi? Yoksa bizim salak
kofteler asagilik bir mangalda can vereceklerini mi dusunuyorlar?
Halbuki ne kizarmasi, parti kuruyor angutlar haberleri yok.
KADIN- Amma konustun ha... Geliyorum tamam.
ADAM-Gitmek istemedigim bir yere sayende acele ediyorum ya, ben asil ona
yaniyorum.
KADIN- Neden gitmek istemiyormussun?
ADAM- Cunku kofteleri mangala dizecek olan kisi senin eski sevgilin.
KADIN-Yine mi ayni konu?
ADAM- Evet ayni konu!
KADIN- Askim o yillar onceydi.
ADAM- Ama o yillarda da sevgililer sevisiyordu.
KADIN- Eee?
ADAM- Ne demek eee? Adamin senin memelerine bakip, siz bir de bunlari
Benim zamanimda gorecektiniz, diye dusunmesi beni rahatsiz ediyor.
KADIN- Kursat'tan adam diye bahsetmen dogru degil.
ADAM- Madem bizim icin adam sayilmiyor neden koftesini yemeye gidiyoruz?
KADIN- Sevgilim yillardir bu sacma konuyu konusuyoruz. Kursat'la yillar
once kisa bir iliskimiz oldu hepsi bu.
ADAM- Ne kadar kisa?
KADIN- Ne bileyim ben, iki ay filan.
ADAM- Memelerini gormesi icin yeterli bir sure.
KADIN- Ben sana ilk erkegim oldugunu soyledigimi hatirlamiyorum.
ADAM- Iyi de bununla gurur duymasan iyi olur. Eski sevgililerinden bir
takim kurma imkânimiz oldugunu biliyoruz.
KADIN- Kabalasma!
ADAM- Peki inceltelim. En azindan basketbol takimi kurabiliriz,
yedeklerle beraber tabii.
KADIN- Anladim sen hazirda sorun bulamadin, yaratmaya calisiyorsun.
ADAM- Hayir. Sadece insanlarin ayrildiklari insanlarla surekli bulusup
gorusmesini anlamiyorum. "Tanistirayim yeni sevgilim, eski sevgilim, bu
da eski sevgilimin yeni sevgilisi, bu da yeni sevgilimin eski
sevgilisi... Ne guzel degil mi? Hepimiz birbirimizin her yerini ezbere
biliyoruz!"
KADIN- Buna cagdas yasam deniyor iste.
ADAM- Nesi cagdas bunun? Bir araya gelmemesi gereken insanlarin toplanip
birbirlerine cagdas cagdas gicik olmalarinin ne manasi var? Zira benim
Kursat'i sevmem tibben mumkun degil. Ama etraf uyuz olmasin diye ona
gulmem hatta belki de kofteleri pisirmesine yardim etmem gerekiyor.
Hicbir sey olmamis gibi. Hicbir ortak yanimiz yokmus ya da bir suru
ortak yanimiz varmis gibi.
KADIN- Son soyledigin cumleyi anlamadim.
ADAM- Kursat'la ortak yanlarimiz, ortak yanlarimizi ortaya koyup dost
olmamiza engel oluyor, bilmem anlatabildim mi?
KADIN- Hayir anlatamadin.
ADAM- Onunla tek ortak yanimiz senin memelerin ve bu ortaklik beni
rahatsiz ediyor.
KADIN- Surekli memelerimden bahsettiginin farkinda misin?
ADAM- Ozur dilerim. Kursat'tan izin almaliydim. Ne de olsa memelerinin
uzerinde onun da hakki var!
KADIN- Bak butun bu soylediklerini sacmasapan bulmakla beraber, eger bu
konuda birisi problem cikaracaksa o Kursat olmali. Cunku o varken sen
yoktun!
ADAM- Tamam iste ben de bu yuzden onu kofte yemeye cagirmiyorum.
KADIN- Acikli olan su... Biz seninle beraber olmaya basladigimiz
gunlerde ben onceki iliskilerimi sana uzun uzun anlattim ve sen de buyuk
bir anlayisla dinledin. Ama sonucta erkek oldugun icin bana sahip
oldugunu hissettigin andan itibaren masken dustu. Tarihime bile sahip
cikmaya basladin! Senden once hayatima giren herkesten nefret ediyorsun!
ADAM- Ama listede oyle adamlar var ki...
KADIN- Kimi kastediyorsun?
ADAM- Mesela o cuce olan, neydi adi?
KADIN- Takiyettin'i mi diyorsun?
ADAM- Evet Takiyettin. Ismi kendinden uzun. Salakliga bak. Bir cucenin
adi en fazla Can olmali. Ama kompleks iste. Ailesi uzun gostersin diye
dikine cizgili bir isim koymus. Takiyettin! Duyan bir sey sansin diye!
KADIN- Aklin sira asagiladigin adam uc kez TUBITAK'tan odul aldi.
ADAM- Biliyorum, yilin en kisa boylu bilimadami odulu.
KADIN- Herkes senin gibi bicimsel bakmiyor olaylara.
ADAM- O da davetli mi?
KADIN- Gelir herhalde. Kursat'in iyi arkadasidir.
ADAM- Hadi buyrun! Ne bu? Eski sevgililer toplanip kongre mi yapacagiz?
KADIN- Kursat'la beni Takiyettin tanistirmisti zaten.
ADAM- Oyle mi? Ne guzel... Ne demisti tanistirirken "Kursat benim boyum
kisa, memelere yetisemiyorum, sen bir baksana!"
KADIN- Sen gercekten cok igrenc bir insansin.
ADAM- Asil igrenc olan sensin. Ben birlikte oldugum butun kadinlari
toplayip pirzola yapiyor muyum? Iyi biz de toplanalim o zaman.
KADIN- Toplanirsaniz haberim olmasin. O kadar besinci sinif kadinin
arasinda gorunmem dogru olmaz!
ADAM- Dogru. Benimkilerin arasinda TUBITAK odulu alan yok. Ama hepsi
hicbir yardima ihtiyac olmadan ust raftan kitap alabiliyor.
KADIN- Bu kadar igrenclik yeter! Geliyor musun gelmiyor musun?
ADAM- Bagirmadan konus benimle!
KADIN- Ben bagirmiyorum!
ADAM- Bagiriyorsun!
KADIN- Geliyor musun sen?
ADAM- Hayir! Gelmiyorum!
KADIN- Sen bilirsin! Ben gidiyorum!
ADAM- Sen benim yuzume kapi carpamazsin! Zikkimin kokunu yiyin! Yalniz
Kursat'a soyle, benimle ilgisi yok, o memeler benden once sarkmisti!

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Winding Instructions for Rolex and Other Automatic Movement Watches.

Instruction #1

For most watches you must first unscrew the crown counter clockwise (12 O Clock Direction). The stem will spring out by itself. Rotate the crown clockwise about 30 revolutions. This will give the watch an initial pre charge. If you do not wear the watch on a daily basis you will need to charge your watch as it will de-wind as it sits. While wearing the watch the kinetic movement maintains the watches power and keeps the time and charge. You will never need to replace a battery as the watch is fully mechanical. We do recommend that you have your watch serviced once a year, as all automatic replicas require. Any watch repair shop should be able to do this for your. Our automatic replicas come with a Japanese Miyoca movement. One of the highest quality Japanese movements in todays market.

Instruction # 2

Please Pull the Screw of the Watch Right till the End until you can move it freely where the Minute and The Hour hand also moves freely. Once you’ re at this point, please push the Screw in gently until it goes slightly inside. At this point you will be Rotate the Screw Freely but the Minute and Seconds hand will not move anymore while turning the Screw. Once at this point, please turn the Screw of the Watch in the 12 O Clock Position (Upwards Position) approximately 10-15 times. While performing this step you will hear the machinery inside the Watch gearing up against each other. Please note that if you hear a very Smooth noise or do not hear anything at all that means you are winding the Watch incorrectly. You need to perform this step once in a while (Once in every 2-3 Days) since it helps keep the watch running much longer than when you do not wind the Watch at all and make the Watch move by Shaking the Watch alone

Setting Date and Time.

Please unscrew the crown (setting knob) of the watch. Turn the Knob from up to down (downwards) you will feel the knob loosen and then it will pop out gently.

Pull out the pin very gently and turn downwards OR upwards in some watches to set the date. If you have a Day and Date watch turn upwards to set the day of the week.

Please make sure you push turn the pin tightly because most cases of Water Damaged watches are caused due to the pin being screwed up not tight enough.