Jump to content

Early shock proof device service

bsoderling

By bsoderling
in Watch Repairs Help & Advice

 Share

Recommended Posts

bsoderling WRT Addict

bsoderling

Posted
Posted

I recently encountered this type of shock resistant design on a Tissot 27 movement. I suppose this is pre-inca early design ?

 

Any advice available how to remove the cap jewel on the balance side?

 

On the dial side the cap jewel can be taken off and the jewel below is exposed. I suppose it can be cleaned as it is but if there's know how around on the dismounting procedure, I would appreciate it.

 

IMG_3535.JPGIMG_3538.JPG

 

 

Sent from my iPad using Tapatalk

Link to comment
Share on other sites
bsoderling WRT Addict

bsoderling

Posted
  • Author
Posted

And it was... two tiny screws from the other side of the balance cock holds the part in place. I must say that I prefer the Inca design. I can't help wondering why the screws had to go in from the other side of the cock...?

But my problems didn't end there...

When removing the complete balance assembly for cleaning, I noted that a tiny shim was placed under the cock to tilt it slightly, probably to reduce the available height for the balance staff.

When mounting it all again (without the shim), I can't get it to fit. The balance staff is simply to short to fit well into the jewels on both sides. And the pivots look ok.

Measuring the length of the staff with my micrometer I get : 3,310 mm

This is exactly the length I find in the documentation to be the correct for the regular (non-inca/non-shock proof) design whereas the Shock-proof staff is supposed to be 3,360 mm, i.e. 50 um taller. 

My suspicion is that at some point someone replaced the balance with the wrong shorter one and tried to compensate for this by tilting the balance cock a tiny amount. I tried to do this but couln't find a working solution.

I would appreciate any thoughts or comments. Am I looking in the right direction here? Can the 50 um difference explain my problem?

 

Link to comment
Share on other sites
bsoderling WRT Addict

bsoderling

Posted
  • Author
Posted

Brilliant! Never too late to learn...

I didn't dare to pick apart the cap jewel holder as you did but thought it would clean well enough as it was.

On a side note... when I use the link provided from my tapatalk ipad app, it takes me to a totally different topic. Had to use the link from a regular browser to get to the right one. Strange...

Any thoughts or comments to my extension of this topic regarding the poorly fitting balance staff?





Sent from my iPad using Tapatalk

Link to comment
Share on other sites
Geo Distinguished Member

Geo

Posted
Posted
2 hours ago, bsoderling said:

Any thoughts or comments to my extension of this topic regarding the poorly fitting balance staff?

Without having the unit in front of me to study closely, it would be difficult to comment on.

Link to comment
Share on other sites
bsoderling WRT Addict

bsoderling

Posted
  • Author
Posted

No worries...

I guess my best option is to hunt for what I think should be the correct staff for the Shock-resist variety and swap out the one currently in the movement to see if my ideas are correct. I have seen a few out there that should be the one I need.

Another issue I haven't mentioned earlier is that the balance wheel sits so low that it's touching the pallet fork cock in some orientations of the movement, which is another obvious no-no that hopefully strengthens my hypothesis that the balance staff is the wrong one.

I didn't pay more than 10 Euro for the watch, so I should have some hobby budget left to explore this ...:biggrin:

I'll post an update when I have something new to tell.

 

 

Link to comment
Share on other sites
  • 4 weeks later...
bsoderling WRT Addict

bsoderling

Posted
  • Author
Posted

Hi guys,

Promised some feedback on this one. 

So I got the presumably correct length balance staff and managed to swap that into the balance wheel ok. 

Next problem encountered was that the hairspring collet was loose on the staff and wouldn't stay in place. Either I managed to widen it slightly or the new staff is a tiny bit narrower on that part. 

I found this video by the amazing Bunnspecial, using a hollow stake in the staking tool to reduce the collet ever so slightly and it worked!!  

https://www.youtube.com/watch?v=OBC1utamM6w

 

 

Finally got all the pieces back into the movement again and it seems to run decently. 

Below is a picture of the assembled watch.

The dial isn't much to write home about, but for now I'm happy that it ticks along and I proved my theory correct about the balance staff being the wrong one. Those things need to be pretty spot on to do their job...

 

Tissot_27.jpg.00ffc7cf7dd568625d784f3bacc61e34.jpg

Link to comment
Share on other sites
matabog Super WRT Addict

matabog

Posted
Posted

I would have tried raising the lower balance jewel assembly (that is if it's friction fit), using a jeweling tool to decrease the axial shake.

Would that have worked, I wonder?

Nice job, anyway! How did the balance staff exchange worked?

Link to comment
Share on other sites
bsoderling WRT Addict

bsoderling

Posted
  • Author
Posted

Hello Matabog,

That would for sure have been an interesting thing to try. I suppose it's along the same thinking as when the guy who mounted a too short balance staff tried to shim under the balance cock edge to tilt it slightly downwards. But your idea should be more correct as it doesn't introduce any angle error (and possibly avoids a bunch of other issues as well)

There's a photo of the jewel setting in the thread. Can you tell from that if your idea to shift it would have worked?




Sent from my iPad using Tapatalk

Link to comment
Share on other sites
bsoderling WRT Addict

bsoderling

Posted
  • Author
Posted

My picture is probably misleading as it doesn't show the end stone that is fixed in a small metal plate that fits in the recess visible in the photo.

Had this been an inca-type device with jewel and end stone integrated as one item, I would assume pushing the entire setting in might have worked...?




Sent from my iPad using Tapatalk

Link to comment
Share on other sites
praezis Super WRT Addict

praezis

Posted
Posted

Some - only few afaik - Incablocs may be pressed without a stopping edge. But if the staff is wrong, usually the calibrated parts of the staff, that stop the displacement by shock, are wrong, too or missing at all. 

Frank

Link to comment
Share on other sites
 Share
Go to topic listing


  • Recently Browsing

    • No registered users viewing this page.

  • Topics

  • Posts

    • HectorLooi
      Without Our Forum

      By HectorLooi · Posted

      Like losing Ranfft. That was a wake up call. We took his website for granted. Miss him terribly.  
    • Neverenoughwatches
      Without Our Forum

      By Neverenoughwatches · Posted

      Its 4 o'clock in the morning here in the Uk, i cant sleep, i dont sleep, not much ever really. My brain never shuts off to rest, I'm just a constant thinker, i have to be very tired to be able to sleep,  i guess eventually it will be my undoing and my health will suffer because of it I'm sure. But while I'm here i want to get as much out of life as i can, and give as much as i can, to help,maybe to make a difference to someone's life if that is within my capability,recent events have made that need even more clear to me. I'm not sure where I'm going with this or why i bring it up , or if its relevant to want i want to talk about its just in my head right now. What i do want to talk about is something thats been on my mind for ages. I like to be prepared,  I'm not fond of surprises because surprises take control away and i am a bit of a control freak at times. This forum, Our Forum if i can call it that, is here because of two reasons. The guy that created it and keeps it funded and the people that joined it.  Without either, it would not exist, and lets face it one day it won't ( I'm a realist and i talk about things others dont or who are afraid to in other words folk that dont particularly prepare for the inevitable). How many of us visit here regularly ?  How many among us almost depend on the forum as a way of socialising because they are stuck at home and how many of us has it become part of a daily routine to check in and see if they can offer advice or get help with something they are working on or just to have a chat and engage in some banter. The members here are in the thousands and thousands have disappeared over the years many had just a fleeting visit. But there are a good few of us that know each other quite well and visit regularly. I dont know about you but i wouldnt want to lose that communication with you all, in all honesty it has become an important part of that side of my life and helps to feed my passion for all things watches. Some of you may think differently and thats ok, some of may stop and think # what would i do " Without Our Forum " # 
    • Neverenoughwatches
      Gamblin Gamsol for cleaning?

      By Neverenoughwatches · Posted

      Naptha appears to be a general name and its content can be varied depending upon what it's specific use is. Lighter fluid as an example can be light or heavier also with other ingredients to help it burn. Try sesrching for benzine ( as opposed to benzene which is linked to causing health issues ) . There are other fluids such as ethanol that you could try and also methylated sprirts, mostly ethanol with a small percentage of methanol added. Experiment with any new chemical to see how quickly schellac dissolves in its presence. I have tried a few things but hexane is not one of them, i understand it does evaporate very quickly.  Be sure sure to check out any safety data on chemicals you try. Toxicity of fumes and flash point information, ultrasonic machines can heat up fluids even without a heater function. And of course always ask here for personal opinions when trying a new substance. 
    • GuyMontag
      What tools does ebay have to offer this week.

      By GuyMontag · Posted

      I have that set and really like it. I prefer that crystal holder over the one that came with my Bergeon claw tool and any time I use the claw I use this one instead of the Bergeon one, just an additional bonus with this tool.
    • GuyMontag
      Movement inserted from crytal side

      By GuyMontag · Posted

      Is the Roamer not a split stem? I'm confused on your how your case is put together. If it is a front loader where is it you are putting the case screws? I love me some Roamer, do you have any photos?
×
×
  • Create New...