Balloon chuck precision

[LittleWatchShop]

Only recently have I employed a balloon chuck.  Once I realized their utility, I decided to try.  I have multiple.  Some I inherited and some from various watchmaker tool lots.

So far...all of them I have tested are imprecise.  Not the problem with the chuck...I checked.  Maybe I am too critical.  But with a pivot wobbling back and forth, how am I going to polish it?

Maybe it is a fundamental problem...dunno...comments??

 

[JohnR725]

8 hours ago, LittleWatchShop said:

imprecise.  Not the problem with the chuck...I checked.

I'm not quite sure what you're saying here?

I have found it typically there is one of the bluing shocks that I have that I prefer so I had the mark that so I know which one I preferred because some they well I just typically don't use some even though I have five or so what work I usually have one that I marked because I know what works well. Sometimes it looks like it's wobbling I just taken out of the 5 mm Chuck that it's in and just put it back in again and it seems to be fine.

Casually from memory any of the ones that have the end that screws off I don't recall them ever being where there supposed to be. But I suspect if they get dropped that's going to be an issue.

 

[nickelsilver]

We had some in school, I found the same, not very true. Our teacher mentioned that when new, the cap has no hole, and you were to drill it in the lathe it would be used in. I kind of doubt that; the ones I saw were on 8mm collet shanks, which if made well, should seat in a good lathe spindle within a few microns each time. But there's the thing; a set of balloon chucks from Levin would pretty certainly be excellently made, and work well. A set from Marshall, they might make the body diameter a bit smaller to be sure it would fit in whatever spindle. That won't repeat very well at all- the body diameter is very, very important- it's not just the angle on the collet head/spindle bore that gives repeatable precision.

 

I never saw the attraction of balloon chucks or some of the little "pivot polishers" that hold the balance between centers, with the pivot to be worked on sticking out a thin support. But we were drilled on Jacot tool use in school, and I keep one set up a meter from my bench at all times.

 

 

[LittleWatchShop]

1 hour ago, JohnR725 said:

I'm not quite sure what you're saying here?

I have found it typically there is one of the bluing shocks that I have that I prefer so I had the mark that so I know which one I preferred because some they well I just typically don't use some even though I have five or so what work I usually have one that I marked because I know what works well. Sometimes it looks like it's wobbling I just taken out of the 5 mm Chuck that it's in and just put it back in again and it seems to be fine.

Casually from memory any of the ones that have the end that screws off I don't recall them ever being where there supposed to be. But I suspect if they get dropped that's going to be an issue.

 

The body seemed to run true, but the hole in the end where the pivot protrudes did not run true.

1 hour ago, nickelsilver said:

But we were drilled on Jacot tool use

I have one...I guess I am going to have to learn to use it!! 

I have Levin step collets.  I put the balance in one of those yesterday and it ran true, but I think I just need to learn the Jacot.

[dadistic]

I've been very curious about balloon chucks.  I haven't really been sure how they are supposed to be used,  I wasn't even sure what they are for!  I'm guessing from the comments that they are for polishing pivots, but I don't see how that works. To me, it looks like the balance is mounted inside the chuck, but I don't see what keeps the balance from spinning freely inside the chuck.  

Now a Jacot tools I understand, I just have to get better at using it

 

[LittleWatchShop]

10 minutes ago, dadistic said:

I've been very curious about balloon chucks.  I haven't really been sure how they are supposed to be used,  I wasn't even sure what they are for!  I'm guessing from the comments that they are for polishing pivots, but I don't see how that works. To me, it looks like the balance is mounted inside the chuck, but I don't see what keeps the balance from spinning freely inside the chuck.  

Now a Jacot tools I understand, I just have to get better at using it

 

@jdricharddoes a pretty good job here.  Quite clever actually.  The pivot protrudes beyond the end of the head.  But to work, the hole needs to be true...thus this thread.

[nickelsilver]

I'm always amazed jd uses his crappy Peerless lathe so much when he has like a dozen others including a beautiful Paulson (made by Boley Leinen).

 

As you can see, you polish the sticking out in the air pivot, in his case with a burnisher, but many in the past used bronze or even wood with polishing paste. In a Jacot, one side of the pivot is supported in a beautifully made bed of its exact size. It becomes almost a challenge to break a pivot. But pivot unsupported... yikes.

 

The Jacot didn't catch on in the U.S. like in Europe, way back early 20th century skilled yanks used "pivot polishers" which were actually sophisticated live spindle grinders to shape and finish pivots. While really useful for many things, I can do both sides of a new staff in a Jacot before you'd even get one of those devices clamped in the lathe bed.

[dadistic]

Thanks for the link. It answered the last question I had, which is that the balance is held by friction, it has to be tight enough that it doesn't spin inside the check as you burnish. 

I'll stick with the Jacot, and as usual, practice, practice, practice.

Cheers!

[LittleWatchShop]

I got my jacot tool out to see that it is all there.  Now I need a vise to mount it.  You got to be able to rub your tummy and pat your head to use it...seems like.

[JohnR725]

8 hours ago, nickelsilver said:

But we were drilled on Jacot tool use in school,

I'm curious about which school. The first school the instructor used a balloon chuck For polishing the pivots and it worked fine. Like any tool if you understand how to use it you can make use of it some tools of course work better than others. The second school I don't even remember seeing anything for polishing pivots at all. But way back when they didn't have Deeper pockets as they did later on.

40 minutes ago, nickelsilver said:

But pivot unsupported... yikes.

Like anything you just have to be careful. Although I would agree the term burnishing isn't exactly what I would think in this set up because I don't think you can get enough pressure but Indefinitely polish the pivots and make them look nicer which a lot of times is all you need.

14 minutes ago, dadistic said:

I'll stick with the Jacot, and as usual, practice, practice, practice.

I once had some old-time watchmaker show me how to use the tool. When he did it it produce the most beautiful black polish I've ever seen so tool is really outstanding but. As he pointed out if you want to be good at it you have to use it in practice every single day basically into a really really good and you probably should still continue to practice. It's like everything else in watch repair it requires lots of practice. Then his other comment made was that your bird assure basically should conform to the shape of your pivots so conceivably you might need more than one burnish her because you may have different curvatures although you may not be concerned about polishing the curved partier pivot.

So for me since I didn't practice and finally sold my tool because I was never using it anyway I just use the balloon chuck. Which for the most part works fine. No matter what if you have some staffs you really should just replace them neither tool necessarily is a miracle fixed to make you a new pivot.

[dadistic]

I ordered a little machine vise from AliExpress, so that it could sit flat on my bench. Doesn't add a lot of height, so It all fits under my microscope.  Hefty little piece of steel,  but this one is a bit small.  I would set up a mounted vice, but it's a little tricky drilling holes in a glass top

https://www.aliexpress.us/item/3256803197259569.html?spm=a2g0o.order_list.order_list_main.5.7370194dDaqeYh&gatewayAdapt=glo2usa&_randl_shipto=US

Mine is the 1.5". There is one that is bigger, The QGG50, that is 2" that I think would work even better.  

Cheers!

 

Edited January 18, 2023 by dadistic
Added picture and text

[LittleWatchShop]

Just ordered this.  Looks similar in size to yours.  We'll see how it goes.

[LittleWatchShop]

Aspiring to become a real watchmaker.

[nickelsilver]

On 1/18/2023 at 9:11 PM, JohnR725 said:

I'm curious about which school.

 

I went to the (then) AWI school, late 90s. In my year they brought in "experts" for each stage. When we got to pivot work, it was a fellow called Ron DeCorte, who broke our balls super hard, but we were making 0.05mm pivots with confidence by the time he left. When I later went to WOSTEP I spent some time learnin' a couple of their full training students in the use of the Jacot. The teacher they had then was very nice, but very hands-off, sink or swim. One of those students (meant to sink) went on to work with a killer artisanal watchmaker, where I worked too in the early 2000s. He went on to work for Dufour, I went independent; still best of friends.

[JohnR725]

4 hours ago, nickelsilver said:

WOSTEP

The interesting thing with WOSTEP Is it's evolved over the years. I don't even know if they even had a jacot when I was there in school in 1979.

[LittleWatchShop]

On 1/18/2023 at 2:19 PM, LittleWatchShop said:

Just ordered this.  Looks similar in size to yours.  We'll see how it goes.

So far, I love this vise.  Its made in America!

[LittleWatchShop]

On 1/18/2023 at 5:49 AM, nickelsilver said:

But there's the thing; a set of balloon chucks from Levin would pretty certainly be excellently made, and work well.

Well, though somewhat against your advice, I acquired these Levin chucks.  They are true!!

[JohnR725]

1 hour ago, LittleWatchShop said:

They are true!!

Outstanding that there are true because oftentimes anything vintage is not.