ETA 2783 - helical stem

[WatchMaker]

I have not one but two ETA 2783 based watches ... both of which need new stems.

These stems seem special in that they are helical i.e. the rectangular section at the end of the stem is twisted. Cousins lists them as 'Obsolete' and whilst I see some on ebay the price seems high for a stem (partly driven by the fact that none are UK based so postage is a factor).

So my first question is why a helical stem? This might well answer my second question which is ... could I 'get away' with a normal stem if I managed to find one that could fit? And, thirdly, does anyone know of a better (UK) source of 2783 stems?

[oldhippy]

They are supposed to increase pressure of the sliding pinion against the winding pinion. You should be able to use the common type providing the sliding pinon is square.

Have you tried this site?

http://www.windingstems.com/

 

[jdm]

36 minutes ago, WatchMaker said:

So my first question is why a helical stem? This might well answer my second question which is ... could I 'get away' with a normal stem if I managed to find one that could fit? 

The helical is needed to properly tension when quick-changing date. From our forum: 

Quote

  I have been so incredibly frustrated- these watches (I bought from hong kong) had wrong stems- (they had 2824 stems and I didn't realize there was a difference---there is), and these springs were not tensioned, so the date wheel would randomly move from one number to the next.  

https://www.watchrepairtalk.com/topic/5728-eta-278384-partsassembly-question/

Then you can go with Marc's excellent guide:

https://www.watchrepairtalk.com/topic/1924-eta-2783/

 

[jdm]

5 minutes ago, oldhippy said:

They are supposed to increase pressure of the sliding pinion against the winding pinion. You should be able to use the common type providing the sliding pinon is square.

No, you cant't. See above.

[WatchMaker]

Thanks oldhippy ... I did come across http://www.windingstems.com/eta.php in a web search but the 2783 comes up with a 'Free Quote' icon rather than a buy price indicating it's not readily available. I didn't think they'd be so elusive!

Thanks jdm ... I had tried to do some due-diligence before posting my question and had come across the 'parts assembly question' you've kindly linked for me. As I read this though the OP had 2783 movements with 2824 stems. I'm not surprised there were then issues as windingstems gives them very different dimensions as per pic below.

I will of course always try and use the correct parts so my question was more a theoretical one for a plan B on whether there's merit sifting  through the hundreds of spare stems I have to try and find one that matches a broken 2783 example albeit without the helical twist.

[rogart63]

I found three stems but i could probably part with 2 if you can't find them elsewhere.

Probably have some more ETA 2763 stems somewhere if i search harder. 

[WatchMaker]

Thanks rogart; that's incredibly kind of you. I'll PM you. ☺

[jdm]

4 hours ago, WatchMaker said:

As I read this though the OP had 2783 movements with 2824 stems. I'm not surprised there were then issues as windingstems gives them very different dimensions as per pic below.

Thanks for posting the comparison. You are looking at the original 2824, but that OP probably had a 2824-2 stem, which has sizes
A=75
E=315
B=110
C=110
D=90
F=39

That is much closer to a 27xx stem, and may almost fit.

BTW, there is also an error for the 2824. Size E is supposed to be A+B+<dimension not specified>, but it reports A+B=160 with E=114.

 

[cadet]

Can you please tell me if I can use an ordinary stem on call 2783 instead of a twisted stem.

 

Thank you.  Cadet

[oldhippy]

Only if inside the clutch wheel is square. If the inside is twisted to take a twisted stem the answer is no. Call 2783 come in two types twisted and squared. You can't fit one into the other.