Jump to content

Help with ETA movements please


Recommended Posts

Hello. I am trying to source a hair spring (does not need to be balance complete) for an ETA 2408. Could you please advise if the hairspring on an ETA 2390 is compatible, and for my own future reference, how do I find such information please? Kind regards, Deggsie

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

The hairspring often are matched by what they call vibrations, so the first you should look so it vibrates/oscillates at the same frequency. Next you have to match the diameter of the spring with the diameter of the balance Wheel. If they are the samme then it might work.  next you look at the balance staff, If these are the same the chances for success has increased enourmously since the collar on the hairspring will sitt tight on the balance staff.
At RANFFT you can find the most except the diamater of the balance Wheel.
http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&2&2uswk&ETA_2390

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&2&2uswk&ETA_2408

Edited by HSL
  • Thanks 1
Link to comment
Share on other sites

Thank you for your reply. It seems it will be taking quite a chance to buy the eta 2390 spring in the hope all the criteria match when I receive it. I think I will hold on an wait for the eta 2408 to come along on eBay. I might be lucky - no hurry. Thanks again, Deggsie


Sent from my iPhone using Tapatalk

  • Thanks 1
Link to comment
Share on other sites

Compatable , a HS out of eta2390 fits on 2408, streigtht away also the space to accomodate the guest is readily available in the new surroundings, the main problem remains, the new  HS and BW team should vibrate to the design beat together, For instance to 18000 beat/ hr. That is how many loud beats we or timegrapher hears per hour.   At this point you are dealing with the length of the HS. The longer the length the longer the period.. To get the beat you need for time keeping of the watch, the only alteration at our disposal is to shorten the HS preferably in increments to approach and not pass by the 18000 beat/ hr vibration. Shortened too much, you need another HS to start all over.

You can vibrate balance wheel- HS outside the movement on a tool specially made for this purpose or vibrate inside your movement.

If the new HS is already too short, it should go back on 2390. You have just lost a bit of the factory poising. 

Regards

 

 

 

Link to comment
Share on other sites

1 hour ago, Deggsie said:

Thank you for your reply. It seems it will be taking quite a chance to buy the eta 2390 spring in the hope all the criteria match when I receive it. I think I will hold on an wait for the eta 2408 to come along on eBay. I might be lucky - no hurry. Thanks again, Deggsie 

If you decide to wait Otto Frei has sometimes good tips and trix in how to choose things and in this case they have written a couple lines about it on their page, Reading is Always a good past time.
http://www.ofrei.com/page820.html

  • Thanks 1
Link to comment
Share on other sites

I'm guessing the part you're looking for is the incabloc and not the  KIF? The part number for Incabloc ETA balance wheel with flat hairspring is 721.

281384193_ScreenShot2019-03-27at11_28_47AM.png.76f15ca9aeda4c9797084ae2ea516d4c.png

When I put this part number into Bestfit, this is what I get for possible replacements:

2144765383_ScreenShot2019-03-27at11_40_09AM.png.38f5717163a825eb74746c26ff81040e.png

MATSYS says only difference between  2390 and 2408 is that Rolex/Tudor uses same balance assembly (2402) with KIF shock protection for its 21Jewel version.

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

Hello all. This forum never ceases to amaze me by the way people are so willing to help out. Thank you so much for all of your very useful replies. It certainly helps to know that the ETA2390 HS will be a ‘direct’ donor part into the ETA2408. whilst I appreciate what NuceJoe is explaining about needing to set the length to establish the correct vibration period, it seems in this case that the HS will not require further adjustment? Is that correct?

And to clarify, yes the BW has Inca shock system. [emoji846]

Many thanks again!!

Kind regards, Deggsie


Sent from my iPhone using Tapatalk

  • Thanks 1
Link to comment
Share on other sites

2 hours ago, Deggsie said:

. whilst I appreciate what NuceJoe is explaining about needing to set the length to establish the correct vibration period, it seems in this case that the HS will not require further adjustment? Is that correct?

And to clarify, yes the BW has Inca shock system. emoji846.png

Many thanks again!!

Kind regards, Deggsie
 

I don't think you'll need to adjust the hairspring.

J

  • Thanks 1
Link to comment
Share on other sites



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Post some pictures , some good close ones of the parts you've described. 
    • Ive never used epilame H only information i have read and mentally stored about it mostly from Nicklesilver here and elsewhere ( the fork horns thing ), maybe the residue powder that is removed has some grinding effect ? So probably a good idea to limit its application areas to only the absolute necessary. Yes as far as i know epilame rubs off relatively easy, the technique of running the watch to make a groove through it first in the pallet stones where the lubrication is then placed. This i understand creates the barrier for the lube to sit up to. If i can find a good balance of pros and cons of its use then thats one process i can avoid by using a thixotropic lube on the stones. The epilame i would say allows for a more fluid lubrication to be used that would increase amplitude on low beat movements. The stearic acid powder is extremely cheap, the problem is the fuming process to coat parts, is not selective , the whole part has to treated in this method. If epilame residue can cause wear then thats not good, if I remember the conclusion was not proved entirely just a general assumption between watchmakers. The thread is out there somewhere, the same discussion is also old on a facebook group. Ive never used epilame H only information i have read and mentally stored about it mostly from Nicklesilver here and elsewhere ( the fork horns thing ), maybe the residue powder that is removed has some grinding effect ? So probably a good idea to limit its application areas to only the absolute necessary. Yes as far as i know epilame rubs off relatively easy, the technique of running the watch to make a groove through it first in the pallet stones where the lubrication is then placed. This i understand creates the barrier for the lube to sit up to. If i can find a good balance of pros and cons of its use then thats one process i can avoid by using a thixotropic lube on the stones. The epilame i would say allows for a more fluid lubrication to be used that would increase amplitude on low beat movements. The stearic acid powder is extremely cheap, the problem is the fuming process to coat parts, is not selective , the whole part has to treated in this method. If epilame residue can cause wear then thats not good, if I remember the conclusion was not proved entirely just a general assumption between watchmakers. The thread is out there somewhere, the same discussion is also old on a facebook group. If its a potential problem for amateurs to use then i would prefer not to take the risk .
    • Following on from my question about identifying screws in the AS2063 movement that basically fell out of the case in bits, I’m pleased to report that I’ve got it all back together, and the movement is running pretty well.    But… There’s something wrong with the keyless works and hand setting. It’s fine in winding and quickset date position - these work - but in hand setting position winding the crown turns the whole gear train.  I don’t really understand how it’s meant to work. It doesn’t have a traditional friction fit cannon pinion.  The second wheel is unusual with a pair of smaller pinions on it, which seem to interact with the barrel and the motion works.    Could this be the problem? I must admit I just cleaned it and popped it in place when reassembling the gear train. I’ve lubricated the pivots but didn’t do anything to the extra bits on the second wheel.    Does this make sense and is anyone able to figure out what I’m doing wrong? Thanks in advance, as always.    ETA - the parts list calls it the Great Wheel, not second wheel. 
    • You're thinking metal to jewel in general I guess. Maybe it would be a good idea to peg the pallet staff jewel hole on the main plate after the epilame treatment. I think that could work as it is my impression that the epilame doesn't sit very hard, but I could be wrong about that so feel free to educate me. I didn't remember that 9501 was thixotropic (thanks for the link). That would mean it's even runnier during impact (lower viscosity) so perhaps it's time I get some fresh grease as mine seems a bit too runny. What I have seen is a whitish surface after washing but it goes away if I scrub the surface with a brush in a degreaser (Horosolv). I don't think it embeds itself in the metal but sticks very hard to the metal. I don't worry too much about the cleaning solution. I just want perfectly clean parts and my solution can be replaced for little money (ELMA RED 1:9). Anyway, I quite often need "to strip back and rebuild" and scrubbing parts by hand isn't exactly the most stimulating part of a service. Just got confirmation that Moebius 9501 has a lower viscosity (68 cSt at 20° C) than 9504 (305 cSt at 20°). The viscosity of Molykote DX is 285-315 cSt at -25° to +125° C. I was surprised to see that the viscosity of Moebius 9010 (thin oil!) is higher (150 cSt at 20°) than my 9501 grease!
    • I’ve had a couple movements where it is clear the previous watchmaker was diligent with lubrication but the old epilam had turned to a fine white powder covering the pallet fork and keyless parts, which can’t be good for parts. I’m spare with epi since I don’t know how long it takes to degrade to that state…
×
×
  • Create New...