Measuring Small Hand Gauges?

[dpn]

Hello everyone,

I continue to be very appreciative of the great advice I've received so far from this forum on a variety of topics.

Here's another hands question:

The Bergeon 30464 Hand Gauge Watchmakers Tool seems like a great tool for quickly measuring and categorizing hand gauges. Its smallest measurement is 0.30 mm, however.

How does one measure smaller second hand gauges? The best thing I can think of would be to use a micrometer on the hand pinions, but given the small difference between, say, a 0.27mm gauge and a 0.25 gauge, there seems to be a lot of room for error with a micrometer.

Thanks, as always, for any suggestions!

-- Dan

 

[clockboy]

I have that tool and have used it many times. If you have a hand that is smaller than the gauge can not measure then you measure the pinion it fits onto.

[nickelsilver]

I use plug gages, which are in 0.01mm increments, but they are expensive. If you need to measure the hole in the hand and can't measure the pivot (and a micrometer will easily differentiate between 0.25 and 0.27mm, you can easily see a difference of 0.005mm), you can use a small broach. Slide the hand on until it stops, and measure there. There's a little interpolation to do, but you will be very close.

[dpn]

Thank you all for the great info! I really appreciate it. Sorry if these questions are stupid -- I like to think things out and talk them out to make sure I understand the correct approach to use on a given problem. I have very little hands on technical experience, and so things that may be obvious or intuitive to an experienced horologist baffle me without additional explanation.

If anyone is curious, the reason I'm asking this question is because I'm starting the process of learning how to heat blue hands. It turns out that plain steel wristwatch hands are very difficult to obtain cheaply, but there is a near limitless supply of old steel pocketwatch hands to practice with. As I practice with these, it'd be fun to measure them and see if I can assemble matching sets in dimensions suitable for use on modern wristwatch movements. 

Edited July 13, 2020 by dpn

[saswatch88]

Digital caliper is what I use. When in doubt always go .01 smaller. You can always broch from there


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[dpn]

5 minutes ago, saswatch88 said:

When in doubt always go .01 smaller. You can always broch from there.

Thanks for the info @saswatch88. Would you explain what you mean by this -- stretching out the small tube on the hand? 

Forgive me if this is a stupid question; I'm a complete newbie, and basic tools and techniques are unfamiliar to me.

I've ordered a Bergeon 30464 and a quality digital caliper, so I should be squared away for measurement.

I will be buying a mishmash of old pocket watch hands, as they're the most cost-effective way of obtaining steel hands for bluing practice. I plan on measuring those hands to see whether I can find any matching sets that fit currently-available wristwatch movements, both in diameter and length. If it's possible to expand or contract a hand diameter using affordable tools, I'll be ecstatic.

All the best,

Dan

[saswatch88]

Thanks for the info [mention=5720]saswatch88[/mention]. Would you explain what you mean by this -- stretching out the small tube on the hand? 

Forgive me if this is a stupid question; I'm a complete newbie, and basic tools and techniques are unfamiliar to me.
I've ordered a Bergeon 30464 and a quality digital caliper, so I should be squared away for measurement.
I will be buying a mishmash of old pocket watch hands, as they're the most cost-effective way of obtaining steel hands for bluing practice. I plan on measuring those hands to see whether I can find any matching sets that fit currently-available wristwatch movements, both in diameter and length. If it's possible to expand or contract a hand diameter using affordable tools, I'll be ecstatic.
All the best,
Dan

Bergeon makes sets of cutting broaches. They are 5 sets for different size ranges. They are expensive but cheap broaches dont work well. Look for a used vintage assortment. A hand holder is needed as well. The broaches will cut some of the metal off inside of the tube expanding it. Just be careful when using them I usually only do maybe one or two twists and rechecking fitment. You can very easily cut too much off.



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[dpn]

@saswatch88

Thank you so much for that great explanation, those photos, and those tips. This is super cool. I'll definitely research this more, now that I know what the correct terminology and tools are. I'm in your debt.

Is there a method or tool for doing the opposite -- reducing the tube diameter? I imagine that some sort of very precise and controlled crimping of the tube would work, but I also imagine that attempting to crimp a small seconds tube down by, say, 0.02 mm with a set of tweezers would be disastrous.

There would also be hand height concerns, of course, but I'm just thinking about whether a hand tube could be reduced to fit on a smaller pinion. Maybe that's the wrong approach too -- maybe its easier to try to increase the diameter of a pinion to fit a specific diameter hand?

Thank you in advance for your continued patience here.

[saswatch88]

[mention=5720]saswatch88[/mention]  Thank you so much for that great explanation, those photos, and those tips. This is super cool. I'll definitely research this more, now that I know what the correct terminology and tools are. I'm in your debt.

 

Is there a method or tool for doing the opposite -- reducing the tube diameter? I imagine that some sort of very precise and controlled crimping of the tube would work, but I also imagine that attempting to crimp a small seconds tube down by, say, 0.02 mm with a set of tweezers would be disastrous.

There would also be hand height concerns, of course, but I'm just thinking about whether a hand tube could be reduced to fit on a smaller pinion. Maybe that's the wrong approach too -- maybe its easier to try to increase the diameter of a pinion to fit a specific diameter hand?

Thank you in advance for your continued patience here.

 

 

some people use a cannon pinion tightener or nail clippers to crimp a Sweep seconds tube, It can’t be disastrous if you don’t know how much force to use. You can very easily just break the tube right off or over crimp it. tweezers has never worked for me. Personally I would not suggest any of these methods unless you are a seasoned watchmaker. I would just invest in some cutting broaches and a hand holder. I find that vintage sets work very well they do not make the steel like they used to. I bought a set from Esslinger for about $25 and they suck. For the same price you can get yourself a vintage set. And the hand holder is about 10 to 15 bucks. 

No the adjustment must be done at the hand not the Pinion. As far as height goes that would mean staking on a new tube and that Requires a much higher level of experience. Even I can’t really do it it’s very difficult. You can shorten the tube just know that you are going to cramp the end when you cut it or file it down. And then you’ll need to use rounding broches to round it back out without removing any metal and widening the inside diameter of the tube.

 

 Keep that in mind that there are two types of broaches: cutting broaches and rounding/smoothing broaches. Smoothing is better used with chronograph hands after cutting, Pivot whole shaping and cleaning.

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