..........Balance Tacks.

After the balance assembly is removed from the movement, it must be put somewhere to protect the delicate components.

I've seen some stored like this (avert your eyes if you're squeamish, I can just see Al and the other pro's wincing).



A slightly better option is to do this, but it still entails flipping the balance and risking the hairspring getting deformed.



Many people prefer to hang the balance on a "tack". This eliminates the flipping issue and the hairspring is free of risk. However, they're hard to find in this part of the world and as you can see below, the cost plus shipping is almost as much as a slab of VB (one military form of bartering currency).



So rather than bitch about it, I decided to make my own. First step to find some suitable non-ferrous rod for the tack. Off to one of my junk boxes.



I had some old clock gongs that have nice bronze rods, At 2.8mm they should do just fine. I decided to use a cork for the base and manage to find a couple of nice wooden corks that would suit. I keep a few corks as they come in very handy. A cork and a toothpick and you have an excellent holder for re-luming watch hands. Anyway, I now had the parts for the job, on with it.



First thing is to remove the cork from the head.



Then turn it around in the chuck to find the centre.



And then drill a 1.5mm pilot hole all the way through, and a 2.8mm hole just through the wood and not into the cork.



Next step is to put a taper on the rod. I find bronze difficult to work on the lathe so the rod was chucked in my power drill and the taper ground to shape on a disc sander.



Back to the lathe to finish the taper with a file and a polishing block with 1200 and 2000 emery paper.



Then the rod was reversed, cut to length and the end cleaned up with a file.



All that needs to be done now is push the tack through the hole in the cork and use a drift to seat it just below the surface.



And job done. A most enjoyable hour or so on the tools and I have two new balance tacks that cost me nothing.



And here they are in their natural environment.



You may notice how wickedly sharp the point is. That's the reason for the length of plastic tube you can see in the tray top left. When not being used I just slip the tube over the tack so I don't risk stabbing myself.

I would take orders from members but I don't have any more suitable wide wooden corks.



Maybe I'll have to get a couple of bottles of Nant just in case the requests start rolling in.

 

A very interesting and detailed write up here

That said, I believe that tacks from suppliers in China are quite cheap on the bay...though maybe a little bit on the wobbly side:



If the time becomes available I will have to start looking into member tools and accessories...

 

@ JimInOz they look brilliant, very nicely done

 

You have missed the point completely...

This DIY makes for an excuse to purchase power tools AND alcohol! It is perfection! The Holy Grail of man-scusing

 

Nice work Jim. Of course no watchmaker I know would actually buy a balance tack. Usually at some point in your training, you are required to make one. Here's mine made in a lathe class years ago:



Of course being a graded project, the methods of construction, materials, and tolerances were a little different than yours. The base is brass stock that had to be hand sawed from sheet using a jeweler's saw, filed by hand to a perfect square (.01 mm tolerance!), tapped hole in the middle, then chamfered and straight grain finish applied. If you went undersize on the square, you scrapped it and started over - this sort of "character building" is common in watchmaking training. Many people had to start over, myself included (I still shudder every time I look at my jeweler's saw).

Then to the lathe, where brass stock is turned for overall diameter, lengths are set out as prescribed in the drawings, and the taper is turned also to meet all dimensional requirements. A die is used to thread the end of the post, and the whole thing is screwed together.

Because I am much better at the lathe than I am with those damn saws, I was last to finish my base in class, but first to finish the whole project. And yes they are sharp as hell - I keep an old cap off an oiler on the tip of mine, but sometimes still manage to stab myself with it...

Cheers, Al

 

That's a beauty Al. Almost too nice to use as a tool.

I can imagine the concentration and skill required to control a jewellers saw that lacks the benefit of a deep blade to help keep it on the line.

And your description of making it from scratch took me back to my early lessons as an aircraft fitter.

Our first assignment was to cut a length of 1"x1" mild steel bar stock and then produce a 1"x1"x1" cube, I can't remember the tolerances but they were very very tight.
The only tools were a hacksaw, files, scrapers, micrometer, engineer's square and Prussian Blue. We were allowed to use a surface plate to check for flatness and perpendiculars but everything else was done by eye.

I even cut up an old leather belt to use for soft jaws as the aluminium workshop ones were embedded with previous generations of student's filings and swarf but about halfway through the phase I got a metal basher mate to bend me up a nice new clean pair, they went into my pocket at the end of every class and I still had them many years later.

 

First thing is to remove the cork from the head.

View attachment 398028

Then turn it around in the chuck to find the centre.

View attachment 398029

I Love the lathe setup. I need to find parts like those. old school quality. Thanks for sharing and for the inspire aspect.

 

Nice Job Jim! And thank you Al for your follow up. Al's tack looks like a real piece of art.

I could not do this kind of job. I kind of have "two left hands" for that sort of things...

By the way, Jim, I am not sure a balance tack should be used to store the balance. I guess it could damage the hairspring if the balance remains too long on the tack. The second position (on your pics) looks much safer to me. As far as i am concerned, I use my - ugly Chinese I am ashamed of now - tack for special purposes such as best rate correction. But may I am wrong - Al may correct me if I am.

 

Quite right François, I'll only use the tack when actually working on a movement. I find it reduces the double flipping and it's easier to lift off the tack and mount to the movement in one motion.

If I have to store a balance it's wheel up in its own container, or back in the movement if I was just waiting on parts.

What! You don't have one of these?

 

Thanks Jim.

I love those tools! But I do not really need one because I do not change hairspring on very old watches - usually I have to change a hairspring I try to ding one in a donor. Sometimes I buy a tool because so like it and find a way to use it later, but not in this case!

By the way, I made a typo in my last post - not the first time I do that here! I meant to say: beat error correction.

 

I only use the balance tack when I'm actually working on a balance. The safest place for the balance is on the movement, but when it's not on the movement or being worked on, it's flipped upside-down and stored inside a container. It's usually not stored like this for long - maybe 15 minutes while doing the initial assembly of the movement...

Cheers, Al

 

Great stuff.

 

tools for expert sure...