Balance tack?

[luiazazrambo]

On 11/27/2020 at 1:38 PM, jdrichard said:

"I always fear the balance cock falling off the movement on installation and the balance staying in the movement resulting in the hairspring getting really stretched. "

That is my nightmare, unfortunately I have witnessed it, not even once and I have not serviced many watches only a handful.

[jdrichard]

1 minute ago, luiazazrambo said:

That is my nightmare, unfortunately I have witnessed it, not even once and I have not serviced many watches only a handful.

Just use your other hand as a guard while you are removing or installing the balance

[ennaj12]

I made some parts for this balance tool i Solidworks and 3D print out the parts in PLA                                             a very strong plastic, even case openersw  resist the forces, otherwise it is good to make different movements holders.  

[praezis]

This tool was sold as "tool for filing balance screws".

Hence the "unknown" pin. Funny that the tool is still made with that pin without knowing its reason .

I had searched some time for # 30673 until I found mine.
I use it rarely but I am happy I have it when I need it.

Frank

Edited November 30, 2020 by praezis

[mikepilk]

I'm trying to figure out if I can make one with just hand tools i.e. hand held drill, files, etc.

I could use solder (and or pins) to fix the back plate,  solder the legs,  and buy a small brass hinge, again soldered on.

The holes for the pin which holds the balance cock don't need to be absolutely vertical.  I can tap them and use screws, but somehow have to turn the end of the screws down to fit the hole in the balance cock.

..... or I could buy a 3D printer  

 

[Tudor]

This is really nice! 

Can 2-d drawings be made from the solidworks model? If so, I can quote having these made. I certainly want one, and the more we do, the less per they will be.

Aluminum will probably be the least expensive, but brass is what I would like to use. Perhaps chromium plating after polish for that over the top look (although we might want to lightly sand blast the top plate so it does not glare at us when working).

Anyone interested?

PS I think the pin sticking out is perhaps a guide for the file?

[Tudor]

I think this is the new version, from our friends at Bergeon...

BERGEON JEWELRY/WATCH TOOL TO FILE AND DRILL THE BALANCES 6903 | eBay

[ennaj12]

Easy to get 2D drawings from model in Solidworks, it is in that program.

I can made them for you.

[nickelsilver]

That's awesome Frank, I've never seen one in a catalog. Since it was a standard student project I always thought they were simply never commercially sold. A Japanese friend here has the 30673 and really likes it, I'm surprised you don't use yours more.

 

Ennaj12, that looks great! I should point out that the semi-circle that presses on the balance rim is pivoted, so that it always presses evenly on both side. Not strictly necessary but a nice detail.

[praezis]

13 minutes ago, nickelsilver said:

That's awesome Frank, I've never seen one in a catalog

An old Witschi catalog from supposed early 50s. It has many funny timing machines from the era. Catched it years ago on the Chaux-de-Fonds museum fair.

Frank

[Tudor]

16 hours ago, ennaj12 said:

Easy to get 2D drawings from model in Solidworks, it is in that program.

I can made them for you.

That would be great. Then I can refine them, with the details we know, and go out for quote. I'll get it quoted in Aluminum (6061) and brass. The big cost will be the labor, so I don't think it will be much different, but it's always nice to have options.

[jdrichard]

I think I will just build this.

[ennaj12]

Here is 2D drawings on the Balance tool, I found it is easiest to have friction fit on the stick that keeps the balance cock. 

[ennaj12]

[ennaj12]

[ennaj12]

[ennaj12]

Finish assembly 

[Tudor]

Thank you very much!

I can't today (parts to inspect) but I'll work up some refined drawings and go out for quote.

Out of curiosity, is anyone else interested in one of these? Making three will be expensive per piece, but price will drop with quantity.

Tolerance will be somewhat loose, so that helps control cost as well. Dies and movement holders have tighter tolerance, so higher cost despite their relative simplicity.

[jdrichard]

1 hour ago, Tudor said:

Thank you very much!

I can't today (parts to inspect) but I'll work up some refined drawings and go out for quote.

Out of curiosity, is anyone else interested in one of these? Making three will be expensive per piece, but price will drop with quantity.

Tolerance will be somewhat loose, so that helps control cost as well. Dies and movement holders have tighter tolerance, so higher cost despite their relative simplicity.

I would be interested:)

[AshF]

Me too

[Tudor]

Ok guys!

Hopefully the bulk of the parts are out of the way now. I had to do like 40 blend repairs today... no power tools allowed. Swiss pattern files and cratex sticks. 

I’ll keep you posted. 

[jdrichard]

Ok, I spend some time today to make a brass balance tack for holding the balance without tension on the hairspring:

1) cut a tack on a lathe

2) tap it with 8-32

3) cut a sheet of brass square

4) tap the hole 8-32

5) cut 2 different sizes slots for the rolled table to fall through

6) screw in the Tack

7) buff etc

mistakes: tack at small angle, need to tap straighter, need small legs (4 blobs of Rodico being used.), lower the balance cock by tapering further down.

 

 

[jdrichard]

Ok, I spend some time today to make a brass balance tack for holding the balance without tension on the hairspring:

1) cut a tack on a lathe

2) tap it with 8-32

3) cut a sheet of brass square

4) tap the hole 8-32

5) cut 2 different sizes slots for the rolled table to fall through

6) screw in the Tack

7) buff etc

mistakes: tack at small angle, need to tap straighter, need small legs (4 blobs of Rodico being used.), lower the balance cock by tapering further down.

[Tudor]

Looks good so far!

Tap the four corners 4-40 and put in four button head cap screws for feet. 

[jdrichard]

15 hours ago, Tudor said:

Looks good so far!

Tap the four corners 4-40 and put in four button head cap screws for feet. 

Solved the leg issue. Former and glued on a piece of Leatherette that not only provides cushion for the lower pivot, but raises the balance so that legs are not required and there is less tension of the Hairspring:) Done!