Movement AS 1187/94

[EdB]

A couple of questions one in regards to the AS 1187/94 and the other in regards to mainsprings. 

So I was able to source a balance complete for the AS 1187/94 and when I installed the balance complete it would not rotate freely when I tightened down the balance cock. I ran into the same issue with another movement different caliber. This on has Inca bloc setting on both the upper balance and lower mainplate. The other movement that had the same issue has capped jewels. I checked the end shake / play and it seemed sufficient, but that's the opinion of a novice. Is there something I should be looking for that I am currently overlooking? It will rotate freely if the screw is backed off slightly. I am currently running it through a cleaning / rinsing cycle in the cleaning machine. 

 

Second question 

I've searched many sites trying to understand how to order mainspring replacements. Every site appears different and some refer to Dennison which I have not found any information about as far as how the numbers cross reference or refer to a specific measurement. What I have also run across is that there does not appear to be exact matches for the spring being replaced. That being said is it better to round up or down for any of the measurement required? I measured length, width and thickness of the old spring. Other then the type of end required I believe this is all of the information that should be required to locate a replacement mainspring. 

 

I guess I have a third question while I'm here. 

Why do some place the screws in the watch cleaning machine and others don't; I'm assuming this is preference; but I would think that if the other parts require cleaning so should the screws. 

 

Thanks in advance for your help. 

 

Regards, 

Ed...   

[HLPayne]

Hi Ed,   I'm new to the hobby and wrestling with the same issue you are having on an AS1187/94.  There is a string on the Facebook "Watch Repair Lessons" Group with this discussion linked below. Basically, the movement has had multiple versions of shock resistors over it's life. You probably have the incorrect staff that was installed by a watchmaker of the past.  The quick and dirty solution is to add a shim under the balance cock. I was advised to use brass shim stock by one of the group members. I picked up brass shim stock from a hobby shop so I hope it works. The other option is to get the correct balance staff for the shock system on your movement. Mine has the Supershock system which uses a Ronda 305 staff and I found it cross references with other movements on the Ronda Catalogue.

BTW, Supershock has capped jewels that require the balance cock to be disassembled to be cleaned. I've added a photo below for your reference.  I found this on the Ronda staff catalogue which I'll like below as well. 

https://www.facebook.com/groups/watchrepairlessons/permalink/807278563210416

 

Question 2 - This Cas-Ker mainspring catalogue, linked below, has a Dennison to Metric conversion and size list.  It has helped my quite a bit. 

https://www.jewelerssupplies.com/media/pdfs/MainspringsCatalog2018.pdf

Ronda Staff Catalogue - (thanks to Vintagewatchparts.net for posting)

https://www.vintagewatchparts.net/ronda-balance-staff-catalogue/

[Nucejoe]

  How did you check for endshake?     its the unforced play on staff "free play" , use an oiler when lifting the balance to check.

Any amount of end shake would free the balance to turn, ideally  its .02mm .

An oscilator with many issues can run, the question is how good does it run.

Shimming is not illegal Europe,  if it comes down to it , shim.

Regs

Joe

 

[Nucejoe]

As HLPayne said, jewel and caps should be removed, cleaned, pegged and checked under good magnification.

 

[JohnR725]

9 hours ago, EdB said:

So I was able to source a balance complete for the AS 1187/94

How did you go about sourcing your balance complete? Now the reason I ask is a lot of times there can be variations. For instance at the second link how many balance completes are there? Looks like there's six separate balance completes usually they're not interchangeable. So if you get a balance complete and it's not the exact one for your watch it will not fit. Then looking at the balance staffs there is even more of those.

So do you have the correct balance complete for your watch? If not you're going to have a problem.

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&AS_1187

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=AS_1187

9 hours ago, EdB said:

ve searched many sites trying to understand how to order mainspring replacements. Every site appears different and some refer to Dennison which I have not found any information about as far as how the numbers cross reference or refer to a specific measurement.

There is a couple a separate ways to order mainsprings. You can look up the watch at a variety of sites and see which mainspring you're supposed to have. Like the first link up above Which lists the mainspring then the second link also has the mainspring.

If you click on the parts found in the second link you usually get additional information Like the dimension of the spraying and two other numbers which you could use to find the spring plus a list of all the watches that use this mainspring it looks to be very very common. If you go the other route have just measuring the spring you want to be careful do not ground up it needs to physically fit in the barrel and if you make it too big it's not going to fit that's going to be a problem. Especially the  first number that is how wide the spring is if it's too wide you're screwed the other numbers you can vary a little bit.

MS-711K

 MAINSPRING 1.60-.10-300 9

 GR 4486

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=qWLXEn

Using the third number up above you can go the cousins website and find out your mainspring is discontinued as least as far as they're concerned. The first number we would use on the site or got the number but right at this instance they claim their databases down and I can't search except he could search for the parts you just can't see if they actually have it or not.

https://www.cousinsuk.com/search?SearchTerm=4486

You will note that the dimensions are all in metric.

Then regarding the first number if you change the first two letters into a word like this Mainspring 711K Then go to eBay it's available there. It looks like quite a few of them are available.

9 hours ago, EdB said:

Why do some place the screws in the watch cleaning machine and others don't; I'm assuming this is preference; but I would think that if the other parts require cleaning so should the screws. 

I don't think I've ever seen anybody not clean their screws? But I can see were somebody nervous about not keeping track of them toward mixing them up maybe that would be why. But as far as I know he always clean the screws at least I do.

 

4 hours ago, HLPayne said:

Hi Ed,   I'm new to the hobby and wrestling with the same issue you are having on an AS1187/94.

I tend to think of each watch as unique. So applying things from one discussion to another discussion doesn't always translate.

4 hours ago, HLPayne said:

The quick and dirty solution is to add a shim under the balance cock. I was advised to use brass shim stock by one of the group members.

For instance in the watch of the original discussion we have multiple of balance wheels and lots of balance staffs to go with the various wheels. in other words we have lots of variations including conceivably pivot size diameter. So adding a  Shim isn't going to help in this particular  case providing that is what the problem is.

 

 

 

Mainspring - DennisonChart.pdf

[nlapietr]

So WRT the discussion on the balance completes, I assume you would order by the shock mount and type of hair spring (i.e. Incablock, flat spring)?  I have replaced several balance completes (wording?) and so far have not had an issue with getting the wrong one, at least not that I have seen.....

[JohnR725]

1 hour ago, nlapietr said:

I assume you would order by the shock mount and type of hair spring (i.e. Incablock, flat spring)? 

Normally with modern watches there's only going to be one. Then that one will fit. The older ones where we of the variations then you should be able to do exactly what I have quartered you have above it should fit.

Where we get them problems is older watches. American pocket watches for instance staff numbers failed to disclose you can have several different pivots sizes. Or there's one particular Elgin watch that I think there's 12 different staffs for one part number. As because are several different pivots sizes for each variation there are several variations. So is not enough to use a part number.

It's where the old Swiss numbering system you look on a parts list and you see that the balance complete is this part number but every single balance complete is the same part number. It's only a modern times did they grasp a problem and the parts all have unique part numbers.

Then of course unhelpful is the parts list. Which I've attached for the original watch in this discussion. We see that the balance complete the 721 and it has a flat hairspring. With no form of shock protection but fails to disclose all the variations because this was the original parts list.

Other sources a reference material are things like the bestfit books a two volume edition books are a bit pricey as an up and published in a very long time but you get the PDF at a bargain price.

If you're into wristwatches providing they aren't new wristwatches sort of? The book was published in the Mid-70s. I'm attaching a page from the book. Providing you know what watch your looking for you to look up and get all kinds of part numbers. You can find out if there's another movement like a bass caliber for the watch. You look up the parts and see if there's variations.

Suppose for instance and I did this a couple weeks ago you have a watch the candidate if I. You can use what's called the fingerprint system the setting parts on older watches are all unique. But I couldn't because the dial was on all I had was the stem and the backside of the watch. Which meant I measured the stem dimensions and in the book you look up stem dimensions. Found several that were close was an automatic watch I went to the section on automatic watches found one matched and were able to order parts.

The book itself is available at this link

https://mccawcompany.com/product/bestfit-encyclopedia-books-111-111a-digital-download-pdf-version/

Then no pictures they also have a online edition that is a little more money than the books. But if you're in the wristwatches in trying to find parts it's really helpful to have this.

https://mccawcompany.com/product/bestfit-material-matsys-for-life/

How do curiosity I went to the online version which I have you'll notice several different balance completes. I also got the mainspring number even though we already had that. Then I went to the http://www.julesborel.com/ Website entered in the mainspring number and snipped out out so you can see it's available brand-new.

Unfortunately finding watch parts is a interesting event that requires work sometimes quite a bit of work. You may spend more time and effort trying to track down parts than the actual repair will take.

 

 

2449_AS 1187,1194.pdf

[Nucejoe]

Pivots on AS1187 came in  10.5"'  and 11.5 "' ,  each fits the other with no issue.

Staff total length varies from 295 to 305, all beat the same,  seems like you have received a longer one, all you need to do is shim the cock. 

I think if a pivot is fitted with different shock system its was made for, the watch will still run, you just may loose some amplitude. You have already observed this to be correct , when oscilator turned freely as you backed off cock screw.