Jump to content

Recommended Posts

Posted

Feeling like a bonehead here, so bear with me. I have a ladies Bulova with 5AH movement. The first disassemble, broke off the ratchet wheel screw (A). Bummer, just ordered another movement, like $10. 

Broke off barrel arbor screw again. Is there any possible way they reversed this ratchet wheel screw (A) on these little movements like crown wheel screw (B)? it makes no sense to me if they did. I would think they would unscrew themselves otherwise. I am just guessing these slowly got really tight when getting close to being over wound and the screw is just so small. 

Order 3rd movement, cheeper than ordering little parts separate. Any tips this next go around?

 

Screen Shot 2022-04-04 at 7.08.01 PM.png

Posted
3 minutes ago, grsnovi said:

Isn't the screw on the winding wheel (over the barrel) usually left-hand threaded?

B was reversed like most watches...my question is about A, that is above the main spring, and connects the ratchet wheel to the barrel arbor.

Posted

I'm too new at this but I thought A is normally left-handed and B is a typical right-hand thread.

Maybe I have that wrong or maybe you were turning each the wrong way?

Posted

The secret is not to use brute force. When I'm unsure, I turn the screw a little both ways to see which way has less resistance. 

I've come across watches with both the crown wheel and ratchet wheel with left hand threads. And yes, they do unwind themselves.

  • Like 2
Posted

Are you holding down the ratchet wheel firm with a piece of pegwood, then unscrewing either clockwise or anti clockwise gently to see which one loosens it?

Also, you’re going to face serious issues lubricating the balance jewels. You have to release the balance wheel first.

  • Like 1
Posted
13 hours ago, JerSievers said:

 Is there any possible way they reversed this ratchet wheel screw (A) on these little movements like crown wheel screw (B)?

Yes. I have come across several movements (recently a A Schild 984) where both the crown and ratchet wheel screws are reversed. Why? I don't know. Of course, I made a note on the pic for future reference.

As @HectorLooi says, if the screw seems tight, try turning it a little the other way. Even if it's not a reversed thread, this can help free the screw.

Barrel-0004.thumb.jpg.7e564bcabc6d77737a9a299a4a25512d.jpg

  • Like 2
Posted
2 hours ago, mikepilk said:

Yes. I have come across several movements (recently a A Schild 984) where both the crown and ratchet wheel screws are reversed. Why? 

I suppose that was to save one tool change and one different screw at manufacturing. 

  • Like 1
Posted
32 minutes ago, jdm said:

I suppose that was to save one tool change and one different screw at manufacturing. 

I was thinking the same.

  • Like 1
Posted

Thanks everyone, I have to believe it is a reverse thread. I can't think with how much torque I had to put on two different movements, that this is the case. 

-Jeremy

  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Well, my fundamental stance is that I want to go in and out without leaving any trace other than a shining, perfectly running movement. So, no scratchings on the inside of the case back lid, no marred screws, no debris, no fingerprints, and so on. That is, my goal is to make it impossible for the FBI to track me down. As a professional, I suppose you might want to keep track of returning watches, but as @JohnR725 mentioned, we can keep detailed computer records without marking the watch at all. That may not be true for every watch, but luxury and COSC-certified movements do have unique numbers. John also says it’s best to leave no sign you were ever there, and I couldn't agree more. Now, suppose the Sea-Dweller I'm working on is one day scrapped, and you want to sell the case-back separately (perhaps the case was destroyed in a plane crash). Then the scribbles on the inside no longer reflect the current movement inside the case. Also, the engraving will likely halve the market value of the case back. It had been "sleeping" for about a week and a half. Yes, the "debris/old lubricant" theory is my hypothesis as well! It will be interesting to see what I find once I have time to start disassembling the movement.
    • I've repaired a few of these, having some success with stripping and cleaning the mechanism.  They are so cheap though, its hardly worth the effort in many cases.
    • Get well soon Old Hippy, torn muscles.,  not good
    • Id love to see how he has the output shaft mounted to this setup, as I have the same rotary stage and stepper in my build.
    • If you see at least one thread protruding, or even a half, then you may have a chance using this "tool", but don't squeeze hard. Lot's of patience, and if you notice any signs of loctite or other adhesives, then apply several drops of acetone on top of broken stem. Use heat (hair dryer) also. You should be able gradually turn it counterclockwise, just like i did on this broken Timex stem, which was glued with something like nail hardener. Then you can use an extender to save your broken stem. https://m.media-amazon.com/images/I/513DVvkfW5L.__AC_SX300_SY300_QL70_ML2_.jpg   You can also try cutting a small grove / slot on top of the broken stem to use 0.7mm flat screwdriver.   Depending on the Crown material and Stem material, you can try dissolving the stem. 
×
×
  • Create New...