Jump to content

Jig or punch base attachment advice


Recommended Posts

ive got this nice little swiss movement made for another bulova im working on.  Actually both bulovas im working have this cam.

When i looked up online to find a spec sheet with mainspring dimensions i stumbled apon a page of a guy who disassebled the watch for cleaning.

During the cleaning he removed the cam, once clean he lubed the arbor before reassembly.  Id like suggestions as to what type of punch base attachment or jig would be successful?? Its gonna have to be tapped off somehow.

Or do i simply clean the part as is and lube tge base and top with pin oilers??

20200729_142946.jpg

20200729_142729.jpg

Link to comment
Share on other sites

Never take that apart. You will never get it together and have it at the correct tension. Clean it in your watch cleaner (if you have one) oil it. If by chance it doesn't carry the hands around it is because it has worn and become loose. Re place is the best. Only an experienced repairer would attempt to tighten this. It has to be the same tension all around, if not the hands will not carry.

  • Like 1
Link to comment
Share on other sites

I do take them apart, but they're tricky. I have a special tool made by Star decades ago but alas 19/20 it doesn't fit. I slide nickel tweezers between the upper and lower pinion, and push on the pivot with the tail end of another nickel tweezer. A Platax tool would work too (about the only good it's for in my opinion).

If you clean it assembled, put some good thick oil like HP1300 at the seam, hold the upper pinion with nickel or brass tweezers and turn the wheel so it works in. Do it a couple of times, then remove any remaining oil with pithwood. If it's not lubricated it will fail and then you have a bigger job on your hands.

  • Like 2
Link to comment
Share on other sites

Another bit of advice: be careful if you use a water based cleaner and don’t dry it properly as this is the sort of part that would need heat to bake the moisture out. 
 

I’d possibly be tempted to just clean it and re-oil, unless you have access to spares. As per conventional canon pinions, do not leave it unlubricated, even if it feels “right” as it will inevitably begin to bind over time and possibly seize entirely. 

Link to comment
Share on other sites



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Yeah ive watched that a few times before,  i couldnt find my old school dividers to scribe it up 😅 Yep thats the guy i bought a roll from .
    • Yes, "Sold out" is difficult to understand. There doesn't seem to be a lot going on. It's been nine months since any new video was published on the Watch Repair Channel. The Level 4 course on watchfix.com has been in progress for what feels like forever (several years!?). Maybe Mark's enterprises aren't doing well or perhaps already so profitable there's nothing much to motivate him for more material. Or, perhaps these days he's more into crochet. The real reason is probably something entirely different but it would be nice/interesting to know. I don't mean to sound gloomy or pessimistic, but I wouldn't be surprised to be met by an HTTP 404. Every day feels like a gift. Speaking of watchfix.com I've been postponing the "Level 5: Servicing Chronograph Watches" course for a very, very long time. Anyway, I just enrolled on it so it's going to be very interesting to see the videos. I must say, IMO there's nothing really that can compete with Mark's courses when it comes to presentation and video quality. It's simply world-class and makes me associate with some really expensive BBC productions.
    • Steel has some funny properties, or at least counterintuitive. The modulus of elasticity is effectively (not exactly, but close enough) the same for steel that is annealed and hardened. What changes is the point of plastic deformation* . If the movement of your spring doesn't pass that, it should work fine. It looks a little thick, I would thin it a bit maybe from the main body out about halfway, maybe 10-20% thinner (not in thickness, along its form). But if it works it works!   *So- if you have two bars of the same steel, one annealed, one at 600 Vickers (general hardness watch arbors might be), clamp them to a table so the same length is hanging out, and put a weight on the ends, they will bend the same amount. But if you continue to add weight, then remove it, at a point the annealed bar won't return to its original straightness. That's the point of plastic deformation. But up to that point, as springs, they are the same. However- their wear characteristics will be very very different. And getting the hardened bar past its point of plastic deformation takes a lot more effort.
    • @JohnR725 now that you've mentioned it. This is actually the second aftermarket spring (same place and brand) I ordered as the first one broke. The eye on which the arbor pulls on, broke off on the first spring after the first wind, and also it was a bit to large for the arbor. Looked like on one the second picture in the 2nd group. The second one was exactly the same, I had to bend it a bit, to give it a more prominent curve to the end of the spring so that the arbor catches the eye.  Also I believe both were 5-10mm shorter. Not that I writing that, I feel a bit dumb, as the spring might actually been the problem all along, although its advertised as a substitute to the original...     
    • The CS70 is the only one they show as annealed.  A further search on ebay, I found CS75 and CS100 annealed carbon steel strips  e.g. https://www.ebay.co.uk/itm/314072784422
×
×
  • Create New...