The forum has not had a comprehensive, correct and detailed maintenance post. I often see only a few pictures of the movement, there is no maintenance explanation of the text. It knows nothing about the technology, equipment, oil products, operating procedures, testing methods, and venues behind it. There are also some misleading views of table friends over maintenance, consumption. As a moderator, I am deeply worried.
In this regard, after the Spring Festival, I had an idea. I took a watch that I should maintain and entrusted my friend Mr. Guo Ming to do a maintenance. The whole process was filmed and accompanied by textual explanations. Some wrong maintenance ideas were corrected and written. An article published here. The purpose is to let more watch friends understand the knowledge behind the watch, use it more reasonably, and maintain their love watch. At the same time avoid unnecessary losses.
Lao Guo was preparing his work for the Basel watch exhibition at that time. There was a lot of work to do, and he had to participate in the defense of the Swiss Association of Independent Watchmakers, so we agreed to do this work after returning to China. Later, the watch friends all knew that Lao Guo successfully became an alternate member of the Independent Watchmakers Association, and his work was also affirmed and encouraged by many masters.
This time I took out an old IWC Portofino watch, which I bought at the Beijing IWC flagship store in January 2010. It has been more than seven years since then and has been magnetized once. During this period, she was more careful and did not perform maintenance. Due to the large number of watches, the real time for this watch is more than 3 years, and the rest of the time lies in the watch box, hand-winding once a month, walking.
When receiving the watch, Lao Guo was taking a class. As a serious and responsible watch teacher, the daily teaching tasks were still arduous and hard. Preparation of lessons, lesson plans, teaching research, lectures, daily assignments, examinations, scoring, practical operations, etc. I know this very well. In addition, as an independent watchmaker, Lao Guo also needs to complete a series of research and development and watchmaking work. He has not had time to maintain and maintain this watch, and only recently took time out.
This time I sent two watches, IWC and Seagull timing. Due to working hours, only the maintenance process of IWC is described here.
The straps of the two watches are not the original ones. I changed the crocodile leather strap and pin buckle of Beijing Watch Factory, which is more comfortable. The seagull watch’s folding buckle leather strap is really uncomfortable. Change to another strap.
The following is the maintenance process, which is operated and explained by Mr. Guo himself
First of all, I checked the appearance details of the watch. I usually wear the watch more carefully. The case and back cover have a small amount of normal use marks, and there are dust and dirt between the lugs. Teacher Guo checked very carefully.
In fact, the hand time is three or four years, and there is no problem, just a comprehensive maintenance is enough, so after demagnetization, test the various data on the school meter and register it. Then open the back cover to continue the inspection and found a small amount of dirt and rust.
Next, remove the ETA2892-A2 movement from the case, and perform a comprehensive disassembly procedure of the movement parts. The dial and hands are placed in a separately closed dial base and a dust-proof glass cover to avoid external dust interference.
While disassembling all the movement parts, complete a careful inspection of each part to see if there are rusted and worn parts. If necessary, this process must be carefully checked with the help of a microscope. At the same time, this process requires patience and takes a long time, which is often easy to overlook.
It should also be pointed out that the clockwork box of modern brand watches (except antique clocks), if there is no water rust, wear, etc. or the clockwork exceeds the service life, the clockwork in the clockwork box usually does not need to be taken out for cleaning . Many brands of watches are not allowed to disassemble and clean the mainspring. If there is a problem with the mainspring, replace the mainspring or the entire mainspring box directly.
It was found that many maintenance personnel in the forum removed the clockwork for cleaning. I hope to draw attention to the fact that no problem with the washing of the mainspring will increase the power output. The multiple washing and installation of the mainspring will only damage the stability of the power output, which is why many brands do not allow the mainspring to be washed. This issue can be written separately in detail later.
Checking movement parts with a microscope
Next, the shell part was processed first, and since I wanted to keep traces of use, there was no sanding.
Therefore, using a high-temperature and high-pressure steam cleaning machine to clean the casing, some greasy or rusty parts can also be pre-washed at high temperature to soften greasy dirt. Then put the shell part into the ultrasonic wave for further cleaning, and finally dry it on the dryer.
Next, it is time to clean the various parts of the movement. First, the first pre-washing is performed by manual cleaning, and then the various parts of the movement are loaded into a synthetic plastic basket. The Acs900 full-automatic ultrasonic cleaning machine is used for cleaning again.
At present, high-end top brands usually use ACS900 full-automatic cleaning machines. It should be noted that the cleaning baskets for the movement parts are generally made of metal. In order to minimize the friction between metal cleaning baskets and parts, Teacher Guo uses expensive but softer materials. Synthetic plastic cleaning basket.
Metal basket and synthetic plastic basket
Put each part into the cleaning basket one by one according to a certain specification, then put it into a professional ultrasonic cleaning machine, and clean and dry according to the set program.
After cleaning and drying, remove all cleaned parts, place them in a space with a dust cover, and start installing all the parts. During the installation process, the uninstalled parts must be stored in the dust cover to avoid dust. Dirt enters.
During the installation of the movement, all prescribed procedures such as refueling, adjustment, and testing must be performed. It should be noted that the installation sequence and refueling must be done in accordance with the requirements of the watch brand manufacturer.
For example, come on, the main system components of the movement must use different watch oils. There are nearly hundreds of oils on clocks, and dozens of them are commonly used. They must be stored at a certain temperature to prevent oil deterioration. . More important is how to use these oils properly. Different brands of movements use different oils, so this is one of the reasons why maintenance personnel need brand maintenance training. Different brands of movements have different maintenance and maintenance practices. Some commonly used watch oils must be stored at a certain temperature.
Teacher Guo will perform some non-proliferation and special lubrication treatments on some movement parts. These operations do not seem to be conspicuous. There is no difference between the same movement and whether it is not made for a short time. After using it for several years, Only then can you discover the advantages of these measures. We will discuss this issue in detail next time.
Complete the procedures for assembly, adjustment, refueling, and inspection of the movement, and start to install dials, pointers, and other appearance parts. It is best to use the matching needle loading core seat and installation tools to assemble these appearance parts. Then install the shell that has been cleaned and dried. These steps need to be done well. A careful and meticulous attitude is the only correct way.
The next step is to detect various data of the watch as a whole, including various data such as the 5-direction swing, polarization, and day difference of the watches T0 and T24. T0 means the clockwork is full, T24 means that after the clockwork has been run for 24 hours, it is necessary to check the various data of each clockwork time period such as T48 for long-powered watches. . The 5 orientations are CH, FH, 6H, 9H, 3H. Some brand movements require 6 or more orientation inspections.
Because there are too many pictures, only three orientations of the data in the case of full bars are selected to explain. Face and face, head down, the swings are: 299, 293, and 271. The 0.0 day difference is: fast 3 seconds, fast 3 seconds, fast 1 second, and then after 24 hours, test the data in different directions again, and compare the detection results between the two to meet the brand data requirements. You can proceed to the next step.
There are two misconceptions to highlight here:
First: Many watch friends still use the daily difference as the sole measure of the quality of the mechanical watch. The daily error is not comfortable for a few seconds, and it is best to have zero error. This kind of viewpoint mentality is not allowed. Senior cousins pay more attention to the stability of the data, such as swing, polarization, and finally the day difference. The daily error of 1 second and the daily error of 10 seconds are not a problem. The important thing is stability.
Second: For example, this IWC, many watch friends also think that when the clockwork is full, the date difference is closer to 0 seconds with a calibration meter, the better, then it is wrong. The structure of the card degree, usually the speed of the day difference will slow down with the decrease of the swing (of course, there will be a situation that the speed will increase with the decrease of the swing, of which we will write another article to discuss). You cannot ensure that the watch is always in a high swing condition 24 hours a day, you must adjust the day difference by a few seconds when the swing is high, to deal with the situation that the watch’s day difference becomes slower when the swing decreases. Therefore, brands that typically use movements such as ETA will require maintenance personnel to adjust the time difference by a few seconds to tens of seconds under high swing conditions. So based on the day difference display of the following 3 pictures, I will adjust it a few seconds faster.
Through the above steps of operation detection, it has fully met the brand’s requirements for various data. Next, there is a deeper detection, which is the detection of automatic winding efficiency.
Some watch friends often reflect that their watches are worn normally during the day, go home and rest at night to remove the watch, wake up the next morning and find that the watch has stopped, which is a typical problem of low automatic winding or automatic winding failure. How can I be sure that the watch is normally qualified after automatic maintenance? Then you need the following automatic winding meter to play.
As for how to test the efficiency of watch winding with this automatic winding-to-table instrument, each brand has its own data requirements. Let’s sell it for the time being. If you have time in the future, write a special article to discuss this topic. In addition, this instrument has a function that can actually simulate the rotation of a human hand to measure the time difference of the watch in the active state, while the watch calibration instrument only detects the time difference of the watch in the static state.
Next, you need to test the waterproof performance of the watch. Before the watch back cover was installed, the waterproof ring has been replaced. Therefore, after the screwed back cover is put into the high-pressure watch waterproof tester to test the waterproof performance of the watch. 3 bar, which is 30 meters of basic life waterproof, but after 5 bar test, still passed the test. If it is not waterproof, you must use a true water tester to perform the test.
Finally, all the procedures are completed and registered. The time has passed 2 weeks from the time the watch was received to the time it was delivered. This time is not fast or slow, and is a suitable cycle. Take photos before leaving for packing. This is the maintenance process of the basic movement. If you encounter a complex movement, more testing steps are required.
The above is the entire maintenance process, rigorous and meticulous, professional and detailed. After Mr. Guo’s explanation, I learned a lot and opened my eyes. Thank you very much Teacher Guo!
This may be the first informative and authentic watch maintenance article. What we see is not only Mr. Guo’s exquisite skills, serious and responsible attitude and strong technical strength, but also a heart of love for watches and an unselfish heart.
After reading the complete maintenance process of this watch, I don’t know how many masters can take a watch so seriously.
There are quite a few things in the society that are just right, intentionally shortening the maintenance cycle, non-proliferation is useless. Once washed in the oil, no qualified, no equipment, no craftsmanship, I hope my tablemates can make a correct judgment through this post. And understand.
thanks for watching
Guo Ming Old Noodle May 21, 2017 in Shanghai, Beijing.