Ecodec

[ecodec]

I get conflicting answers on this question so perhaps someone can help me. I need a new watch movement for a case I have. ETA is Preferred. Is the movement of a wrist watch measured from the auto winder at the back to approx the date ring level or is it measured from the back to the top of the hand spigots. Thank you, I hope someone can help. Regards, Mike.

[StuartBaker104]

Here’s a good example showing where this 5.67mm height Miyota is dimensioned from

http://miyotamovement.com/pdf/draw_821A.pdf

 

[anilv]

Ecodec, there are many variables but all it takes is the correct movement ring and you can usually make anything fit.

1. Diameter of the movement must be smaller than the hole in the case... (of course!)

2. The hole for the stem in the movement must line-up exactly with the hole in the case. (single most crucial aspect).

To achieve this, the movement spacer will have an appropriate shape to fill the gap in the case (between movement and case) exactly and also have some mean to ensure the stem is correctly aligned with the hole in the case. Easy enough if you have a lathe or can measure things accurately enough to get one made up. The dial is an important factor as well as most movement spacers depend on the dial to limit the depth of the movement (prevent it from going deeper in the case).

Once that is done you need to ensure that the crystal does not foul the hands and the case back has sufficient clearance (his is especially true for automatics).

This are just the basics but in reality its a can of worms. You may find that having the stem hole in alignment leaves the dial floating. You then have to either raise the dial (thereby requiring a taller cannon pinion, hour wheel etc, or leave the dial in place and get a new spacer made to fill the gap between the dial and case (rehaut).

Is is quite common now to assemble your own watches using parts bought from the internet. There are a lot of clone 6497 movements, dials + hands and a lot of cases meant for these movements available and it would seem simple to assemble a nice watch but even here I've seen some dodgy stuff where the dial thickness is not consistent with the original design of the case (which usually comes with a movement spacer) which leaves the stem hole out of alignment with the case hole.. Result .. broken stem.

Anilv

[ecodec]

On 11/16/2017 at 3:01 PM, ecodec said:

I get conflicting answers on this question so perhaps someone can help me. I need a new watch movement for a case I have. ETA is Preferred. Is the movement of a wrist watch measured from the auto winder at the back to approx the date ring level or is it measured from the back to the top of the hand spigots. Thank you, I hope someone can help. Regards, Mike.

 

[ecodec]

Thank you all for your kind help. The Miyota drawings are very helpful. Thank you all very much. Regards, Mike.