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Stem Length on Screw Down Crown - Seiko NH35 Movement


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Hi All

I bought a Seiko NH35 movement on ebay 2 or 3 months ago.  Long story short, I bought a case, strap, dial and hands.  The issue I have is getting the stem length right.  For the crown to screw down as intended, the stem is then to short to use the functions at each position.

When unscrewed to be free of the thread, it is past the point where you can wind (as winding just screws the crown back on at that point), Trying to start the thread just changes the date. The only thing that works is time adjustment as it is at the full extent of the stem.

Am I missing something?

 

Edited by Jonno65
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2 hours ago, Jonno65 said:

Hi All

I bought a Seiko NH35 movement on ebay 2 or 3 months ago.  Long story short, I bought a case, strap, dial and hands.  The issue I have is getting the stem length right.  For the crown to screw down as intended, the stem is then to short to use the functions at each position.

When unscrewed to be free of the thread, it is past the point where you can wind (as winding just screws the crown back on at that point), Trying to start the thread just changes the date. The only thing that works is time adjustment as it is at the full extent of the stem.

Am I missing something?

 

So to have the date set and winding fuction to work the crown did not screw down fully ?  So I'm assuming at this stage you had not cut the stem and tried it as it came ? So then you cut the stem and now it is too short for the date set and winding to engage before wanting to screw back down ? Can i ask how you cut the stem ? Was it in one go ? Two goes ? Easy to cut it short when gauging how much to lob off it. Theres not a great deal to play with, you want to be aiming for everything working with just maybe a thread or two left for the crown to hit home. Then gradually reduce the stem all the while checking the functions. Bit of a ball ache as the crown will have to be on and off a few times as you reduce. Slowly slowly catch your monkey. With practise gauging it get easier. Of course the screwdown stem tube might be too long but if the crown takes it all up then it should be ok. Reducing the tube maybe not a great solution as it may well affect the water-resistant seal. I would guess that you've just cut the stem a little to short. 

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3 hours ago, Jonno65 said:

Hi All

I bought a Seiko NH35 movement on ebay 2 or 3 months ago.  Long story short, I bought a case, strap, dial and hands.  The issue I have is getting the stem length right.  For the crown to screw down as intended, the stem is then to short to use the functions at each position.

When unscrewed to be free of the thread, it is past the point where you can wind (as winding just screws the crown back on at that point), Trying to start the thread just changes the date. The only thing that works is time adjustment as it is at the full extent of the stem.

Am I missing something?

 

I encountered a similar situation, with a NH35 movement and aftermarket NH35 case, basically the tube on the case is too long, meaning that once the crown finishes unscrewing you are already in the date change 'click' and have skipped the winding 'click'. I used a spare stem and shaved a fraction of a mm away trying again and again. Now the watch in question JUST remains in the winding position once unscrewed.

I don't think there is an easy answer, you end up in a catch 22 situation if you lengthen the stem, as you would now be able to wind it up, but you would not be able to screw it down as it would be too long. I did consider filing a mm or two off the tube length, but like I said I just got it to work without having to go down that road (thankfully), and I'm not sure if that would have created more issue than it solved?

Sorry I don't have a solution, but I feel your frustration.

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39 minutes ago, RichardHarris123 said:

Assuming the stem is the correct one and works with the movement out of the case, is the case to large?  If so you may need a  stem extender. 

Usually the stem provided with the movement is some overlength ready to be cut to suit.  Unless the case is huge with a thick case ring to hold the movement. Completely guessing here, making up a watch is not something I've got into or am interested in really.

9 minutes ago, Waggy said:

used a spare stem and shaved a fraction of a mm away trying again and again.

Good practice waggy, if you can cut once and file once then you are frequent stem changer 😅

17 minutes ago, Waggy said:

did consider filing a mm or two off the tube length, but like I said I just got it to work without having to go down that road (thankfully), and I'm not sure if that would have created more issue than it solved?

That is something i would do if the settings still weren't right as long as the gasket still sealed. The fault would be too much of the stem taken up in the stem tube / crown depth. 

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