Seiko 7T32 main plate repair

[systeman]

This was an interesting repair to a Seiko 7T32 main plate, they're hard plastic.

The yoke spring stud on the plate broke away, therefore there was no spring compression.

I had to drill a small hole through the plate and insert a small diameter piece of metal stud as a fix.

Paper clip to the rescue. I used a small length of thin gauge paper clip for this and secured it with epoxy resin.

The setting lever had to be modified though to allow movement and so as not to interfere with the stud.

 

 

 

Oh what fun.

[ro63rto]

Quite a common problem on these movements.
Great fix [emoji106]

Sent from my Honor 5c

[systeman]

 

Quite a common problem on these movements.
Great fix

Sent from my Honor 5c
 

I found the piece that broke off in the case. A very fragile plastic stud indeed. But the fix is quite easy though.

[ro63rto]

Indeed.
Seen it on the 7t34 too.
I suppose any plastic gets brittle after 25-40 years so we'll see more of this unfortunately.

Sent from my Honor 5c

[rogart63]

Had a YM57 movement plate. It looks like it is reinforced at that point . That is a very much same movement as the 7T32/34 

Sorry for the dark picture. But think you can see the stud? 

Edited July 2, 2017 by rogart63

[Watchtime]

Nice fix....

[StuartBaker104]

Nice fix. I have one of these on my bench right now waiting my attention. It belongs to my Dad and I gave it a full strip down a couple of years bck, so was worried I had done something bad to it.

What were the symptoms? I have winding stem won't stay in and moving hands past mignight will not advance the date.

I wasn't really looking forward to stripping it down as I recall it being a pain to reassemble, and I've been looking for a working donor at a reasonable price (note that Cousins currently has the complete movement in stock at £62.50, but he says he'd rather put that to a new watch if it came to that)

[systeman]

The winding stem will loose proper function because the setting lever will not engage the yoke properly in normal, first and second positions.

If you attempt a repair, the stud diameter really only needs to be about 0.6 to 0.75mm and protrude above the main plate by a fraction more than the thickness of the yoke spring that engages it. Be careful when positioning the stud. You may see where it's broken away from, if not then either use the image on the right by Rogart63 above, or assemble the the clutch wheel, stem, yoke and setting lever and note the position of the yoke spring at rest. The stud position will be just under the spring. The spring needs to be under tension. Don't forget movement of the setting lever, it must not interfere with the stud in all three stem positions.

Regarding the date setting, that's probably something different. If its not turning over when you turn the stem in third position, the date wheel is broken and possibly a few teeth on the hour wheel as well. This can happen when someone tries manually to change the date between 9pm and midnight. An easy fix though.

[ro63rto]

Stuart, this series from our friend George will help with the date fault as described above.

Part 1:

Sent from my Honor 5c

[systeman]

 

Nice fix. I have one of these on my bench right now waiting my attention. It belongs to my Dad and I gave it a full strip down a couple of years bck, so was worried I had done something bad to it.

What were the symptoms? I have winding stem won't stay in and moving hands past mignight will not advance the date.

I wasn't really looking forward to stripping it down as I recall it being a pain to reassemble, and I've been looking for a working donor at a reasonable price (note that Cousins currently has the complete movement in stock at £62.50, but he says he'd rather put that to a new watch if it came to that)

I forgot to mention, if the date wheel or hour wheel need replacing, Cousins have these in stock. There should be no need for a new movement. The movement is serviceable, just don't use tweezers (only rodico) on any of the plastic wheels. Follow the assemble procedure in the service PDF from Cousins.

[StuartBaker104]

Roger, Paul, thanks for your help

[GeorgeClarkson]

@systeman, that is a very nice fix, I had thought about doing something similar on all the 7t32/34/36 I have with similar issue, but never had the courage to do it actually. Might do it now that I saw your post, though. Could help me in repairing these watches in the future as well.

 

@Rob3rto: thanks for posting my video

Edited July 11, 2017 by GeorgeClarkson