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Sf240 vs st2555 second hand spacing
Posted: July 9th, 2021, 10:03 am
by mountaineer
Does anyone know the second hand spacing from center pinion on an sf240?
I was thinking of trying a build with a st255 movement. There is a second hand at 9 o’clock. The spacing is 8.2mm from center. This might allow for a second hand and full size numbers on a 37mm dial. Similar look to sf240 dial spacing.
Not sure about hand sizes and availability. Also, does the movement even fit into common cases we use.
Re: Sf240 vs st2555 second hand spacing
Posted: July 9th, 2021, 10:58 am
by Emilio
Don't quote me on this, but back in the day I tried building my budget LP watch with one of those and a 240 dial.
The sub seconds hole was off by just 0.1 or something like that.
Re: Sf240 vs st2555 second hand spacing
Posted: July 9th, 2021, 12:30 pm
by Emilio
I will try to source the blueprint of the movement for you.
Re: Sf240 vs st2555 second hand spacing
Posted: July 9th, 2021, 2:22 pm
by mountaineer
@Emilio thanks for the help. I am also thinking about a fun “budget” build.
Re: Sf240 vs st2555 second hand spacing
Posted: July 9th, 2021, 7:11 pm
by Emilio
@mountaineer found it!
st2555 (made by Seagull) is the same as yt2555 (made by low end Chinese factory)
offset is 8.20mm
Re: Sf240 vs st2555 second hand spacing
Posted: July 9th, 2021, 7:43 pm
by mountaineer
Emilio wrote: ↑July 9th, 2021, 7:11 pm
@mountaineer found it!
st2555 (made by Seagull) is the same as yt2555 (made by low end Chinese factory)
offset is 8.20mm
Thanks Emilio! You mentioned you think a stock sf240 dial fit within .01mm. Do you know the approximate seconds offset for an sf240? I could enlarge the seconds dial hole or custom dial.
Re: Sf240 vs st2555 second hand spacing
Posted: July 9th, 2021, 10:35 pm
by mountaineer
I found the answer to my question on NW’s site. 240 sub dial spacing is 8.9mm from center.
I think a 240 dial should fit on st2555 movement. Might take a little filing to enlarge hole.
Re: Sf240 vs st2555 second hand spacing
Posted: July 10th, 2021, 5:06 am
by Kp0y
Not even close.
This is sf240 dial on TY2555 movement.
Maybe on paper 0.8mm is not much but on reality it is a lot.
Re: Sf240 vs st2555 second hand spacing
Posted: July 10th, 2021, 6:29 am
by Belkin12
Kp0y wrote:Not even close.
This is sf240 dial on TY2555 movement.
Maybe on paper 0.8mm is not much but on reality it is a lot.
Agree. 0.8mm is a real abyss when speaking about subsecond distance.
Отправлено с моего iPhone используя Tapatalk
Re: Sf240 vs st2555 second hand spacing
Posted: July 10th, 2021, 8:42 am
by mountaineer
@Kp0y thanks for the pics.
It might be cost prohibitive but a custom dial might look good with correct sundial spacing.
This woul allow for a 37mm dial, full number 9 and seconds hand.
It not be worth the effort because of hand sizes movement height.
Plus, I don’t even know how reliable the movement is.
