Measuring pivot diameters

[Bonzer]

I'd be interested to know what are the best ways to measure pivot diameters to help determine jewel sizes. 

I have a tapered gauge from a Jacot tool but wondered whether to either try an obtain a Seitz pivot gauge or maybe JKA Feintaster micrometer as that would help with other things too.

What do you use? 

[JohnR725]

19 hours ago, Bonzer said:

Seitz pivot gauge or maybe JKA Feintaster micrometer as that would help with other things too.

Both of these are excellent things to have. Then ideally you want both of them not one or the other. The micrometer is just good for all kinds of things not just pivots. The pivot gauge is nice because often times people measure the pivot and will pick a jewel it's too tight. Where we drop it into a hole you can see if it feels right you basically get a better feel for whether the hole sizes going to be correct or not.

[Bonzer]

Thanks. I think this comes under the maxim that 'you can never have too many tools'

I'd better start saving then

Another question:

If a jewel is slightly too loose, can the hole be closed and then reamed to the jewel size?

[nickelsilver]

Another thing that makes the Seitz gage useful (essential in my mind) is with small pivots it's very easy to form micro flats on the pivot with a regular micrometer that uses a screw. The JKA is different in that it uses a light spring to close, but it's not as accurate as a screw mic.

 

If a jewel is slightly loose you can (usually) close the hole a bit so that it holds, but it doesn't always work. Sometimes you have to ream up to the next outside diameter, if you have a jewel that size. Or you can ream up, or preferably bore in a faceplate, perhaps 0.6mm oversize and make a bushing to take the correct jewel.

[mikepilk]

On 2/4/2023 at 11:00 PM, Bonzer said:

I'd be interested to know what are the best ways to measure pivot diameters to help determine jewel sizes. 

I have a tapered gauge from a Jacot tool but wondered whether to either try an obtain a Seitz pivot gauge or maybe JKA Feintaster micrometer as that would help with other things too.

What do you use? 

I measure VERY carefully with a micrometer, or I use some of the spare Incabloc chatons I have - you can look up the hole size, and find one that just fits with a little play.

[Jon]

I use a bench micrometre; JKA Feintaster. Although, they are going for silly money these days. Five years ago, you could pick them up for less then £100. Now they are triple that!

A jewel gauge is useful too, as someone has already said, it's handy to check the pivots 'feels' free in the jewel.

[Bonzer]

7 hours ago, Jon said:

I use a bench micrometre; JKA Feintaster. Although, they are going for silly money these days. Five years ago, you could pick them up for less then £100. Now they are triple that!

I have been looking at the Feintaster but as you say.....frighteningly expensive at the moment!

[JohnR725]

9 minutes ago, Bonzer said:

have been looking at the Feintaster but as you say.....frighteningly expensive at the moment!

What you want to do is set up a search on eBay for the items you're looking for and yes you can specify a price range and then just wait and watch. Is amazing what will come up sooner or later at really good prices. True nowadays they're few and far between but it's amazing what will come up on eBay sooner or later at a good price you just have to be really really patient

then it depends upon where you live in the planet. For instance in the US if you belong to the national Association of watch and clock collectors they have meetings. Their chapters all across the country when they have meetings though the a lot of them will have tools sales or a march for they sell stuff just depends on the chapter. Then blotted chapter's pool their resources and have a regional meeting that definitely has a Mart region by stuff and then once a year this a national meeting which also has a Mart for buying and selling stuff. This is where I picked up most of my tools over the years were the regional meetings before he eBay came in. People and by stuff to get whatever it is they want to then sell the rest it really bargain prices so that's where I picked up my Feintaster. Just can't quite remember the price it seemed really really good at the time though.

So yes there are other things in eBay out there the problem is you have to find them. But even eBay if you just keep an eye open and your patient wonderful stuff will show up at a nice price

 

[Neverenoughwatches]

9 hours ago, Jon said:

I use a bench micrometre; JKA Feintaster. Although, they are going for silly money these days. Five years ago, you could pick them up for less then £100. Now they are triple that!

A jewel gauge is useful too, as someone has already said, it's handy to check the pivots 'feels' free in the jewel.

I also use a bench micrometer, a bergeon,  accurate and smooth operation with a very light touch. Have measured hundreds of staffs and stems with it. I can see Nicklesilver's point though . At x 40 i couldn't see any noticeable damage on the few that i checked. Thats not to say there wasn't any that was less visible. 

[LittleWatchShop]

My Dad left me a JKA and a Seitz.  I picked a Bergeon screw-type micrometer on ebay.  The Bergeon is my go-to for quick measurements, but the JKA is my reference for accuracy (The formation of the measurement pads is really handy for staffs).  I can see that the Seitz tool is probably the gold standard.