Can you share this source then?
I recently acquired a Weishi 1900 timegrapher, and have been running a few watches through it.
I found somewhere on the inter web what are "good" figures for amplitude and beat error, and spd speaks for itself.
But, should I measure flat, or vertical, or all and take an average? The angle of the watch on the device, I mean.
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Can you share this source then?
You take an average over 5 position.
Dial up
Dial down
Crown up
Crown down
Vertical with crown on the side
Usual practice is to fully wind then leave for about 45 mins to an hour before testing. Allow at least 30 seconds between positions changes before taking a reading, so the movement can settle a little.
Standard practice is to set the time to the second and check after 24 hours with the dial down too.
Hope that helps.
Cheers,
Gary
http://www.wristtimes.com/blog-1/201...-a-timegrapher
Thank you Gary, very helpful. I found the article above which gives some guidelines for the results. Do they look right to you?
I'd say they're okay as a rough guide. It depends a lot on the movement and whether it's a new or vintage watch of course.
I make new watches so my parameters are a bit tighter than those mentioned in the article.
Rate: -4/+6 spd in 5 positions.
Personally I try and set them to an average of +2 spd overall. If I set them to precisely 0 spd over time the movement will slow and no one likes a watch running slow.
Beat error 0.0 - 0.5 in all 5 positions
Amplitude: Minimum 250º at 0 hour (full wind) and no less than 200º after 24 hours. This sounds a bit low but a cal.775X for example can drop as little as 20º over 24 hours. Max 320º, obviously you don't want it to start knocking.
Cheers,
Gary