Rate isn't everything! What you need to know about " timegrapher readings"

The rate isn’t everything, what you need to know about timegraphers.
 
Nowadays timegraphers have  become very affordable and are starting to become a key selling point for many hobbiest collectors. But what does it actually do? And why is rate not everything?

 
Thinking that you know the right answer is more dangerous as being unknown in the subject. It seems harsh but it is sadly the reality. Many people look at a reading and see for example +30s/day and they will automatically say ‘ NAH the watch is not worth that much, I’ll be spending 150€ on a service to fix that’ while they ignore a healthy amplitude. Rate is easy fixable but amplitude is the real key factor and I’ll explain why!
 
Terms:
Rate: the rate difference a watch has on a day. To get the exact rate one should measure the rate in every position and make an average of these numbers. This is not an exact sience but it will get you in the ballpark.
Amplitude: the amount of degrees the balance moves around. The balance is the heart of the watch, this does really show the health of the watch. The factor one actually should look at when buying a watch! What numbers should you look for? For starters George Daniels wrote about the fact that 220 degrees is the natural amplitude and the maximum amplitude a watch can physically reach is about 320 before it starts killing himself.
Daniels, G. (2011). Watchmaking. Bloomsbury, USA: Bloomsbury USA.
Swiss watches:
Modern: 275+
Vintage: 240+
Japanese watches:
Modern: 240+
Vintage: 210+
 
B.E. What is that? The beat error. The difference between the tik and the tok of a watch. Normally one looks for a beat error between 0.0 and 1.0; in very old watches ( 1940’s etc) the beat error should be around 0.0-2.0 but the chances are real this is even up to 5.0; you should not worry about this because the way to fix this is very difficult, the impact if rather low compared to the risk of breaking the balance pivot. ( The pivot your watch heart is running on!)
 
Here are some examples of watches that are running good or bad from both Swiss and Japanese heritage:
A 5513 from 69 with a great reading
Here is an example of a 1969 Rolex 5513 with a solid amplitude and a good rate.
A typical Japanese reading after service on 60's automatic seiko
A serviced King seiko 56cal. Notice the lower amplitude compared to the Rolex. This is completely normal for a Seiko from the late 60's with a high beat movement.
A superb reading for this vintage Tudor. One of the reasons this watch gets such a high amplitude is the use of a stronger mainspring in service. 
A typical seiko 6117 reading. Some can go up to 270 degrees but anything above 210 after a service is considered good.
A typical Pre-service reading on a vintage watch. Sub 200 degrees of amplitude and a rate as crazy as the movement of hair during a metal concert.
A solid reading on a Seiko 6206. Early 60's movements do have the potency to get up there with the swiss amplitude wise.
This watch screams for a service.
 
Thank you for the read! Hope to see you here soon again!