-
Recently Browsing
- No registered users viewing this page.
-
Topics
-
-
Posts
-
…here’s a factory shim on a supposedly high quality movement…as I said it’s a lovely shim, though… -
Bending the balance bridge does seem to be an acceptable method as is taught in school and after all the Swiss make a nifty tool. But? Something was bothering me this discussion has gone on for five pages for one watch? One of the things we have to be very careful about when teaching watch repair on a discussion group is our observations of what's going on is based on the posting person making observations. The problem is if the person making observations does not actually grasp 100% what's going on will we become the idiots? so for instance bending the balance bridge why would we do that? Typically if it's been bent by somebody else and were restoring it back to wherever it's supposed to be. Or basically the Swiss are using it to fine tune the end shake. But it appears to be if I'm reading correctly we have a variation of 0.5 mm which is not a minor amount of end shake. this is where when you read five pages of discussion it becomes kind of a confusing mess so I would not recommend bending the balance bridge until we figure out exactly what's going on. So while I'm not a big fan of shimming which is extremely popular with @Nucejoe I do think it's perfectly acceptable until we actually figure out what's going on. -
By Neverenoughwatches · Posted
? I don't know what you mean holds the arms ? The internal spring in the spindle should allow it to hold up to the rivet and the hub of the staff. But that means taking off both the collet and the rolle. With a figure of 8 calipers that have the correct nibs fitted you don't need to do that to true a balance wheel. -
Hi Richard I get it from master finish.co.uk email *****@*****.tld contact is Nia but sometimes they have no stock so a bit of a wait but it’s not cheap £15 per tin last time but I did buy six so may be more. Dell why does the site hide email address but it is sales at masterfinish co uk -
I have been recently servicing an Omega 3220A chronograph movement which uses a Dubois Depraz 2000 chrono module. This has been quite a time consuming project, not necessarily difficult but with lots of steps. Working on the chrono module is like working on the love child of a hugely complex keyless works and a Timex pin pallet movement. I do have access to a couple of Omega tech sheets and a couple of relevant Youtube videos (including Mark Lovick's Breitling series) so I feel confident that I have all of the required information. The 'tractor' movement (effectively an ETA 2892) had no issues with obtaining 300 degree amplitude dial up / dial down and maybe a spread of 7 seconds across all of the positions. I serviced the chrono module and when reinstalling it, this brought the amplitude down to about 260 degress with the chrono stopped and 200 with it running. The Omega specification states that the chrono running should see the amplitude drop by no more than 40 degrees (from, I am guessing, the assembled amplitude i.e. chrono stopped rather than just the bare tractor movement). Obviously this isn't good enough. I am going to have to redo the chrono module again. Where I suspect I have a problem is inconsistent / over oiling of pivots. For some reason the Omega technical guide states to apply oil to the bottom pivot of each wheel and then place in the jeweled base plate. In practice, I managed to smear oil on the horizontal base of the wheel which would be smeared over the outside face of the jewel. This also wouldn't be helped by dragging the wheel around trying to get the lower pivots to engage in the the jewel. When I watch Mark service a similar Breitling chrono with DD module, he also oils the bottom pivots and installs the wheels (obviously doing a better job than me!). My question is, why can't I install the wheels dry and the oil the jewel on the other side of the base plate in the conventional way? The top pivots are oiled through the jewels in the conventional way, so why would the lower pivots be any different? Looking at the those jewels (picture below an example from a different movement) it looks like there isn't an oil well in the outside surface of the jewel around the pivot, so perhaps I would be better applying a drop of oil directly to the jewel hole before installing the wheel? Perhaps the jewels have different arrangement to conventional jewels because the outside face is installed against the dial side of the tractor movement and we don't want to risk oil migrating from the module to the movement. There are also a couple of friction springs that may have an impact on amplitude, I will recheck their pre-load but these should be OK. Is there anything else I should look at as a source of friction in the DD module?
-
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.