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How do you measure balance staffs?

bkerr

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Do you have any special tools?

I have three differnt tools that I have used. I took some pics of all three. The best one is marked Germany. Has anyone ever seen one of these before?
If any of the German reading guys take a look I'd like to have the instructions interpeted.

BTW you will see a staff in the tool, look ma no hands!!
-> posts merged by system <-
?? something happend to the next page.

I'll wait to see if it pops up. Lots of snow comming down right now:eek:
 

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movement2009

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I am not expert but have dial gauge (the last photo) and have play with it.
The time I need to measure the balance staff is to make a new one for the broken one. The last one is the best for measuring dimension of the different parts of the balance staff but it is not handy.

When the new staff is on the lathe, you can't use these tools if you are not turning it between center. Another tool for measure balance staff is the pivot gauge (hope I use it properly?!) but it is rather difficult to "read" correctly especially when you are talking about the control of 0.01mm. I made a mini caliper (with mitutoyo mini head) for such measuring and I also making a mini "height tool" or mini "comparator depth gauge" which I found from books, can't find such tool in the market.

Would like to hear what other's experience:)
 

Jerry Kieffer

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I am not expert but have dial gauge (the last photo) and have play with it.
The time I need to measure the balance staff is to make a new one for the broken one. The last one is the best for measuring dimension of the different parts of the balance staff but it is not handy.

When the new staff is on the lathe, you can't use these tools if you are not turning it between center. Another tool for measure balance staff is the pivot gauge (hope I use it properly?!) but it is rather difficult to "read" correctly especially when you are talking about the control of 0.01mm. I made a mini caliper (with mitutoyo mini head) for such measuring and I also making a mini "height tool" or mini "comparator depth gauge" which I found from books, can't find such tool in the market.

Would like to hear what other's experience:)
My personal method of cutting staffs is as follows.

If I have the dimensions, I first cut the work piece to the exact length of the staff. This has always saved a lot of time and fitting headaches. The only measuring tool that I use, is a small starrett no. 232 0-.500" Micrometer.
It is used to measure overall length of the work pieces and diameters only. I also no longer use a graver to cut staffs in favor of machining the staffs in the same manner the originals were machined. When machining a staff, I measure diameters using the small micrometer as a reference point. From that point final diameters are machined using handwheel settings under magnification. The final diameters are checked again using the micrometer. Lengths are measured using Gage Pin diameters by optical comparision. I have found this to be far more accurate than any combination of measuring tools I could come up with. Pivots are machined until they are a "Sticky" fit to the balance jewel. This fit is checked by holding the jewel in a special #7 tweezers I made up similar to a pearl tweezers. Two "Eyelets" were silver soldered on the tips that allows the jewel to be securely held for the fitting process. A Balance jewel can be seen held in the tweezers in the attached photo.
From the point of a Sticky fit, I then polish to a final fit to the balance jewel that is used for that pivot.


If I have no staff dimensions, I first measure across the in place cap jewels using the micrometer. I then subtract the cap jewels for a over all length.
The sample staff diameters are measured with the micrometer. The lengths are measured using Gage pin diameters by Optical comparision.

Jerry Kieffer
 

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movement2009

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Always glad to hear from Jerry. Your tweezer is very attractive and I will try to make one, thanks for sharing.

After reading your post, I found I use the wrong word "caliper" it should be micrometer, I found an old photo. It's light weight and compact.
micrometer.jpg :)
 

bkerr

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Excellent guys, I may take the liberty and make up some of those tweezers. I have a small set of metric mic's as well. For some reason my pics did not go through the first time but here is a staff in the tool taking different measurements. The other tools require hold the staff with tweezers. More than one has gone across the room never to be found!

The tool is from Germany - are they still made? Where can you buy one? I have a friend who saw mine and would like to get one but, he is not getting mine!:D
 

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RunesS

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The tool is from Germany - are they still made? Where can you buy one? I have a friend who saw mine and would like to get one but, he is not getting mine!:D
Yes it is. We use some of them at The Danish School of Watch- and Clockmaking. One of the danish suppliers have them on their website.

http://www.lindholts.dk/vrktj/hndvrktj/mleinstrumenter.html

It is in danish i'm afraid. But if you scroll down to the bottom, there it is!

Best regards Rune B
 

Dushan Grujich

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Good Day,

To measure staffs when turning I use an JKA Feintaster much like the one shown in the earlier posts.

Depth gauges, such as the Levin, are available from Rudolf Flume and are made by Mitutoyo. Alas, 250 euros seemed too much to me so I made myself a surrogate, a comparator gauge, by modifying an old drafting compass. With it I can transfer dimensions either from an old staff and compare to the work or to the JKA dial micrometer. It works out to be quite accurate and incredibly useful.

http://s005.radikal.ru/i212/1001/cd/239c9311b2eet.jpg

There is another tool which I have, I did not do any work on it, I've just put it together. I needed a small, but hefty, dial gauge stand which I could use on my bench. So I found on fleabay a surplus Star staking tool frame, with a bore 8 mm in diameter, just perfect to accommodate a standard 2-1/2" digital dial gauge. A small steel table came with it having single centred hole 4 mm in diameter, again perfect, it could use the stumps meant for Seitz jewelling press.

The only thing I made for it, are about a dozen stumps to fit 4 mm bore which can be seen next to the brass pushers which I made for Seitz jewelling tool for setting the watch hands. (I bought one extra Seitz press, paid for it $29, and I use it only for setting the watch hands, adjustable with micro-metric screw to 1/100 mm.)


31.jpg http://s001.radikal.ru/i194/1001/d1/a91cb2e9c677t.jpg

The real advantage over the mechanical dial gauge like JKA is that with digital dial gauge, one can set zero anywhere, add or subtract measurements, and it is vertical, it can be pre-set to any start value as well. One can use a blind stump, or one with the hole, put a staff in the hole and take measurement without worrying if the staff is aligned with axis of a dial gauge.

And the stand cost was only twenty euros, for the Star staking frame.

Cheers

Dushan
 

bkerr

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Now I have two projects tweezers and a new measurement tool to make.

Some pretty smart guys!!:D

Those brass stumps are great!
 

movement2009

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Good day Dushan, may I ask what is the total length of your depth guage so I have an idea how big/small it is. Also, can you explain what is the purpose for the shape of the tip of your tool? It looks like the structure of a broacher?


The idea of using staking tool frame and stumps to measure the length is excellent!
Many thanks.

Thanks Bkerr for having such great post.
 

Dushan Grujich

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Good Day, movement2009

I shall try to answer your questions.

... may I ask what is the total length of your depth guage so I have an idea how big/small it is.

http://s004.radikal.ru/i206/1001/85/5de22e4a5bc8t.jpg

... can you explain what is the purpose for the shape of the tip of your tool? It looks like the structure of a broacher?
The tip of the gauge is of the shape of the "D"
style drill bit. The purpose is to allow one to come as close as possible to the staff and measure the length of staff, in lathe, without removing it.

Namely, without the cut-out it is quite awkward to securely rest the tip of the gauge e.g. on the seat of the balance wheel and measure the top balance staff height or some other axial length. One can always shape his gauge in any way which suits the particular purpose. Keep in mind how a single gauge will never be enough.

The idea is explained in detail in the book "Precision Time Measures" by Charles T. Higginbotham, as I have already stated earlier in one of my posts in this forum.

To aid my self further in taking measurements of the unfinished staff while in the lathe, I use "Dixième" for taking all radial dimensions.

http://s002.radikal.ru/i197/1002/5e/c5410ecb6dect.jpg

Dixième precision, 1/10 mm, is quite sufficient for turning of the staff, as the final sizes are arrived at during the finishing.

Of course I am talking of turning a balance staff with hand graver, steel wire held in lathe collet and all turning done in one go, no reversing of the staff in the collet.

http://i067.radikal.ru/1002/08/bc2f6a5b0196t.jpg

Typically the end result, a balance staff, looks like the one on the image, ready to be parted and have pivots finished in the Jacot lathe. Pivots are about 1 to 1-1/2 one-hundredths of a millimetre in diameter and after finishing they shall get to be exactly 9/100 mm.

I hope this shall help You.

Cheers

Dushan
 

Dushan Grujich

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Unfortunately I have made a mistake in my last sentence, it should read:

Typically the end result, a balance staff, looks like the one on the image, ready to be parted and have pivots finished in the Jacot lathe. Pivots are about 1 to 1-1/2 one-hundredths of a millimetre larger in diameter, and after finishing they shall get to be exactly 9/100 mm.

My apologies for the error!

Cheers

Dushan
 

movement2009

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Good Day, movement2009

I shall try to answer your questions. ........


Thanks Dushan, much appreciated. I will try to get the book you mentioned, hope it is not out of print now. Sorry I can't visit the forum everyday so I have missed some of your valuable posts. I am sure I need to search all your previous posts.:)
 

RJSoftware

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Hello Dushan.

Great tools..!

On your digital guage.

I am curious how you can adjust the guage to hit on different shelfs of a staff, to get measurements.

Only thing I could think of is one of your custom brass stumps has offset so the stump could be turned/rolled to provide a different shelf for the guage to land on.

(hard for me to explain this)

otherwise, if a staff where only be able to be dead center below, directly under the guage tip, it would only be able to land on one spot.

Having a stump with a small offset post would be able to be turned to expose different shelves.

The only way I can think to make an offset stump would be to drill a hole offset peen in a post and then grind smooth.

I like the other tool, the modified compass.

You got me checking out my kids compasses. :D

You know, kind with the two needle points. Cheapy one.

Wondering if I can modify one of them. I like the way you have the measuring part towards ends of handles as the more distance the cleaner/clearer the measuring.

I am thinking of grinding tips flat. Maybe bend tips inward a touch so that just a very small portion touch.

RJ

 

Dushan Grujich

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Good Day, RJ,
I am curious how you can adjust the guage to hit on different shelfs of a staff, to get measurements.
For taking measurements of balance staff diameters I use my other dial gauge, which is very much like the one shown in the post #5.

281.jpg 282.jpg
The vertical gauge I use for taking measurements of the balance staff heights. Nevertheless, I can use digital vertical gauge to measure staff diameters as well. To do so I use different kind of stump, like the Seitz stump (shown below) which is normally used to adjust canon pinion friction. I use it in combination with a sapphire needle point tip mounted on dial gauge.

http://s61.radikal.ru/i172/1003/e6/a09f0785fca7t.jpg

Only thing I could think of is one of your custom brass stumps has offset so the stump could be turned/rolled to provide a different shelf for the guage to land on.
BTW all of the stumps I have made are made from hardened steel, ground square and the surfaces used for measurement are highly polished. I use them in my Seitz jewelling press as well, so they all are placed on a wooden strip together with brass pushers which I have made for setting hands on watches and are used with Seitz press. Brass pushers are in the back row and steel stumps are in the front.

https://mb.nawcc.org/

Having a stump with a small offset post would be able to be turned to expose different shelves.
That is not a bad idea either.

I wish You luck in your attempts to devise your own tools. Making one's own tools to suit particular needs and habits is the best way to go.

Cheers

Dushan
 

Dr. Jon

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I alos use and recommend the JKA Feintaster

the JKA Feintaster design was sold to Interapid who made some for Bergeon. Frei still has them in their catalog but they are no longer in the Bergeon catalog.

I use the Feintaster for most measurements but sometimes I also use a microscope with a micrometer.

There are two flavors that are useful.

1) Is a stage micrometer. It has a micrometer controls in two dimensions so you can move the staff under cross hairs and measure distances.
2) Is a filar micrometer. It is an eyepiece with a thread/hair that moves under micrometer control. It also has s scale perpendicular to the thread which helps keep track of the dial readings.You need to calibrate it by measuring a known object. This has the benefit that you can rotate it to align the scale and motion along the axis of what yuo are measuring. Another advantage is that you can measure in part in sequence and collect dimensions of each part and get a total length when you reach the end of the staff. Getting better than 1/1000 mm is fairly easy.

Filar micrometers are hard to find but fairly cheap when you do. They will fit any microscope that takes standard eyepeices.

For work in the lathe I use a spring loaded dial guage. A micrometer is too heavy and likely to break a pivot. My spring loaded dial guages have knife edge jaws so they can measure the work along its axis and pick up tapers.

This approach used to be quite expensive but old microscopes with these can be bought for less than a Feintaster. It is also a better way to measure pivots and can also measure jewel holes. It's non-contact making it pretty safe.

The down side of the Feintaster and spring guages is that they can go out of calibration so you have to check them often.
 

RJSoftware

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Hey Dr. Jon.

>>I use the Feintaster for most measurements but sometimes I also use a microscope with a micrometer.

This might be a bit much to ask, but, any chance of posting some pictures here of both the microscope and the Feintaster in use?

Definitley curious about this.

RJ
 

Dushan Grujich

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The down side of the Feintaster and spring guages is that they can go out of calibration so you have to check them often.
Good Day Jon,

Well, this is a new one for me. Never happened so far. I have and use a number of different dial gauges. I check my dial gauges regularly against a set of standard gauge blocks of ISO tolerance Grade 0, traceable to national standards institute.

How does that happen?

Cheers

Dushan
 

Dr. Jon

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I find that the mounts that attach the jaws bend slightly and when that happens they go out.


I have a few very precise round standards I use to check to make sure all my gauges read the same.

Also the Feintaster has some adjustment and the I had to tweak the two jaws to get them to agree.

I found that when I did what Dushan did.

I'll try to post some pictures but getting a view through the filar might be tricky.
 

Dr. Jon

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Here are some view of my microscope with the filar micrometer.

On the left is a side view. The secnd view os of the filar micrometer eyepeice. Th eknurled screw on teh right locks it in place on the microscope tube. This allows for fine adjustment of magnification and alignment along the staff axis.

The third is a view through the eyepiece. The long vertical line moves under control of the divided dial on the left. The horizontal red line points to the moving indicator. The upper diagonal to the horizontal reference and the lower diagonal red to the 1/10mm division. I also put in some numbers which are there but out of view of the photograph. The views through the micrometer are 2 millimeters, 1 mm and about .5mm. One complete turn moves the line one small division so the dial indicates 1/500, 1/1000 or about 1/1500mm.

The field of view ranges from 2mm to about 3/4mm. The stage micrometer allow the item to be stepped along to measure up to several cm of length.



The right view is the from the top. The red lines point out the dials on the stage micrometer, one moves vertically the other horizontally.
 

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Dr. Jon

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The microscope and micrometer in the previous post are by Bausch and Lomb I'd guess from the 50's but I am not very familiar with microscope styles. Here are some vies of another filar micrometer. In German its called a Scraubenmikrometer.

This is a lovely instrument but it does not work as well as the less attractive B&L. Its return spring is too weak so it is sluggish in one direction and its not well matched to the power of my microscope. It is easily calibrated and if my other one did not work so well I'd use this one. It has a moving cross hair.

I think this one is lot older I'd guess about 1900 but it's only a guess.

In their day this kind of setup cost a lot more than dial gauges but microscopes with this setup are not much desired and when you find them go pretty cheap, especially when you consider what they are and cost new.

I paid well under $100 for the B&L set up which included the three objectives several eyepieces the case and some junk I will probably pitch.

This micrometer was well under $50 if I recall correctly.
-> posts merged by system <-
Here are some spring micrometers,

The one on the left is my workhorse for checking small dimensions on the lathe. The next shot is a close up of the jaws. They can work a bit loose so I have to carefully re-zero it. I have no idea who made it. I replaced the thumb piece. I used a plastic tubing plug which I filled with epoxy putty.

The next one is what it replaced. I've had this one a long time. It comes out of the case so it works well for checking work on the lathe, Sadly its calibration is wrong. I included a shot of its jaws.The pivot for the counter is gone and I have not replaced it.

The last shot is a standard. these are identified to 0.0001" precision and my digiatl micrometer, by Brown and Sharp is within that tolerance. For my 3.189mm standard the one on the left reads 3.190 +/- 0.001. The other reads about 3.210 or about a 1% systematic error.
 

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RJSoftware

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Very nice instruments Dr. Jon. Your post are much apreciated.

Dr. Jon>>The third is a view through the eyepiece. The long vertical line moves under control of the divided dial on the left. The horizontal red line points to the moving indicator. The upper diagonal to the horizontal reference and the lower diagonal red to the 1/10mm division.


RJ>>So, you can view for example a balance staff that you freshly cut and see if your measurements are in the ballpark.

RJ>>If you have this microscope attached to the lathe, I suppoe you could cut and measure while your working. (no need to stop -take measure -cut, stop -take measure -cut etc...).

RJ>>But, I am also guessing that the accuracy may be rough. So you might fine tune by measuring with the instrument when the cuts get close to where they need to be (do a rough cut with the microscope).

RJ>>Wonder what is the working clearance with a microscope such as these? I want a scope that I can attach so I can cut -see and measure same time.

RJ>>That would be the best arrangement I think. But, we all know how reality goes, always a snag somewhere...!

Dr. Jon>>I also put in some numbers which are there but out of view of the photograph. The views through the micrometer are 2 millimeters, 1 mm and about .5mm. One complete turn moves the line one small division so the dial indicates 1/500, 1/1000 or about 1/1500mm.

Dr. Jon>>The field of view ranges from 2mm to about 3/4mm. The stage micrometer allow the item to be stepped along to measure up to several cm of length.

RJ>>Stepped along.... do you mean that you can adjust the scale for larger or smaller scale? Not sure I understand.

RJ>> Do you use this gridded microscope for staff cutting?

RJ
 

dross

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Jon,

You wrote "I have no idea who made it." If I understand correctly you have a Waltham Watch Company gauge if it measures in mm.

Here is mine with W W Co. marked on it.
 

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Ansomnia

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I'm away from home at the moment but I have tools relevant to the original question. I actually posted my photo before but people probably forgot about it.

I picked up a number of spring-loaded measuring instruments from the Hamilton watch factory in Lancaster, PA some time ago. The tools appeared to have been set up for production work - they seem to be very effective for repetitive measurements for checking tolerances within a preset range. They feature sharp tempered steel jaws that vary in shape depending on their function.


Michael
 

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Dr. Jon

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RJ

I use the microscope for measuring the original staff only. I sorry I did not make that clear in my posting.

Microscopes for use in lathe cutting are tricky to use for direct measurement. To my knowledge the only way to get reliable measurements is to move the or use a calibrated filar micrometer. Other wise parallax is an issue. It is possible to get around that by using special micro lenses (Called telecentric) and video cameras. That gets into real money.

My B&L microscope is not useful during cutting. I also have an opthomological surgical microscope I bought to use on my lathe. Its a lovely beast but I have found that surgical loupes work a lot better and i don't use it much.

When I use my micrometer microscope to get large dimensions, I use the stage. Its similar to the step and repeat technique used to make integrated circuit chips. I usally mount the staff on a carrier to fit in the stage micrometer and embed it in Rodico. I can also get most of the staff measurements before I cut it off the balance.


Before I start to cut I make a dimensioned drawing of the original. I have a form I made in Powerpoint that has the generic sketch and blanks for all measurements. I use the microscope to fill in the blanks and the form to be sure I have all the dimensions. I use the staff shape and nomenclature from the Bulova course material.

The form also has entries to change references so I measure lengths from these while the work is in the lathe.

The Feintaster is also good for length dimensions but for things like pivot diameters, details of the conical part and shoulder heights the microscope works best. Where the Feintaster is good I use to cross check the microscope measurements.

I expect that after I have made a few dozen staffs, I will be able to do it by eyeball but I am not there yet.


I use the spring loaded micrometers during cutting. Because I use several instruments it is important that they be in calibration.

My "school" instrument is a bit easier to handle for checking parts in the lathe but its calibration is wrong. Since i don't know how to re-calibrate it I still use it but only for very small dimensional changes. If I know I have to take off a few thousandths I'll use it instead of the other gauge as do the final trimming.

Dross, thanks for the attribution of the Waltham gauge. Mine is in mm. My only reservation is whether Waltham made it , just stamped their name on it to keep it from "walking off", or just had it private labeled for them.

Whoever made it did a nice job. Its easy to use and not too nasty to service. Its spring is heavier than that of my school gauge and has less clearance inside the jaws so I still get some use from both.
 
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movement2009

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Anyone use digital microscope? This toy is made in Taiwan (many China copies with poor quality and less power, avoid!!!)- Dino, the price is nearly double if you buy it from Bergeon.
The xy stage table is from second hand market.

attachment.jpg


attachment.jpg

The resolution of the photo seems not good but is acceptable, the accuracy depends on the calibration, (I am still a fool in this issue!!!) it is not convenience as a hand-held measuring tool because connection to a computer is needed and I need to take a snap shot before you can get the dimension with the provided software.

KK Au
 

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RJSoftware

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Thanks Dr Jon for excellent information.

KK is the software like a CAD program where you have to give it one known demension?

Very interesting setup..!

(You guys are heavy into this, this is encouraging).

RJ
 

movement2009

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Thanks Dr Jon for excellent information.

KK is the software like a CAD program where you have to give it one known demension?

Very interesting setup..!

(You guys are heavy into this, this is encouraging).

RJ
You need to read(guess) the magnification power (when you set the enlargement) and then tell the software what is the magnification power is. After reading the experience of other members, I think I better buy a "standard gauge blocks" and include one every-time I take the snap shot. This I can check if the magnification power that I input is correct.
This toy (really like a toy when compare with other watchmaking measuring devise!) is rather new to me and would like to know how others use it.

KK Au
 

Dr. Jon

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I like the digital microscope a lot. Its major benefit is major reduction in arithmetic errors which I find I make distressingly often.

If or when I start replacing staffs as a business I will seriously consider getting something like this.

I would also check out its accuracy near the edge of the field. Unless you get specially made optics this can be a real problem and these telecentric optics are not cheap.

The major down side is cost. Measuring microscopes like mine were also once very expensive but now can be had for well under $100 for the whole thing, particularly if the case has cosmetic issues.
 

RJSoftware

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I have a copy somewhere of cad/cam program that I bought cheap off ebay.

What I use to do was get persons who wanted a finial cut to send me a photo of the wood finial and I would use it in the cad/cam software.

The problem is that people often didn't have an original finial to take the photo of or would shoot the picture at a slight angle.

The cad/cam software required a straight on shot to get the profile AND one known distance.

So you introduce the photo into the cad/cam and set some distance with the known portion of the object and the cad/cam would generate all the other distances.

With the larger world of wooden finials I could print out an actual size print and then adhere it to cardboard and cut out a template for turning.

It was a nice process, but, the wood work was a bit much work for what I was charging.

Took about 1/2 a day with wood setup, lathe work and cad/cam processing.

I could not see charging much more than $20 for the work. I don't think people would really want to pay much more than that.

Besides in that world, you can guestimate and be satisfied with results.

I suppose then simply taking a nice photographic shot of a balance staff and then introducing it into the cad/cam would be the equivalent if the only primary objective is to obtain the measurements.

The cad/cam includes a grid which is also nice for following the progress of curves.

But, I don't think that simply measuring is the goal. It has to be a live process. Where I can see as I cut.

For now, (for me) I am settling with good ol magnification of an eye loupe. That and I don't even posses a crosslide (YET...!)

I have been thinking of super gluing two straight edge razors on one of my calipers and cutting angles on the razors so to make its probing capable.

I'll glue the razor blades facing each other and against each other with the caliper closed.

Then when I go to measure, I open the caliper and the 2 edges can do the fine placement. That sould be good for measuring shelf distances.

For overall length I'll just use a regular micrometor.

RJ
 

Dushan Grujich

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Good Day!

I have decided to come back to this thread because I have acquired an interesting measuring microscope the other day. The scope in question was made by Czechoslovakian company Srb & Stys in Prague between WWI and WWII.

MS-08.jpg MS-06.jpg MS-07.jpg

The scope was used as a forensics tool for examination and measurements of barrel traces on fired bullets. It consists of an optical head with a cross hair and complete head can be moved by a micrometer allowing one to make measurements with resolution of 1.0 micrometer. The original object carriage is missing, nevertheless it can still be used for precision measurements including balance staffs. I have tested it for accuracy against the standard microscopy slide and I am very pleased with it.

Field of view is 6.0 mm, visible in the eyepiece, the magnification is not marked on the scope, it appears to be about 15. Scope is made out of solid brass, it is quite rigid and it weighs somewhat over 8 lb. There is a prism in the optical path which provides normal non inverted image allowing easy use of the scope.

The scope design is quite interesting, by elliminating inherent errors in optics, which is used only for centring and not for the measurements, it makes a very good measuring tool.

Cheers

Dushan
 
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RJSoftware

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Nice. Interesting history for it too..!

Any chance you could take some pics of a balance staff in it..?
 

D Magner

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Dushan,
That is a neat scope. I would like to have something like that. I like that the head looks like it could be swung to the rear or even removed & mounted to something else and still be used as a measuring device. Unique.

Measuring diameters is usually pretty easily accomplished, it is the lenght to a step or shoulder that can be difficult to measure. I have the die plate off one of the smaller K&D staking sets that is ground top and bottom. To measure to a shoulder, place staff into a appropiate hole and measure total thickness of staff and plate with micrometer. Substract plate thickness & you have accurate measurement from end of staff to shoulder.
David
 

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Dushan Grujich

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Nice. Interesting history for it too..!

Any chance you could take some pics of a balance staff in it..?
Good Day!

I have tried to take few shots of the balance staff magnified in scope, unfortunately I could not do it with my Canon, I shall have to use another camera with an adapter to do it.

BTW I have done some further tests as I was curious of the magnification of the scope. The results I have come up with are following: magnification 24x, depth of field is a bit more than 2 mm (0.080"), field of view is 6.0 mm (~1/4") and horizontal travel of the optical head is about 30 mm (~1-1/4") while the micrometer reading is up to 25.0 mm (~1.0"). Distance from the lens to the object is 50.0 mm (~2"). The scope column is 200 mm (~8") high, when the optical head is lifted to the uppermost position it allows insertion of the object carriage up to 50.0 mm high with optical head in its lowest focusing position. The optical head vertical travel, along the focusing ways, is 40.0 mm (~1-1/2").

The optical head can be swung around the column (diameter 22.0 mm, ~7/8") and it is also possible to remove it from the stand and mount elsewhere.

MS-12.jpg

There is a spare Boley & Leinen WW lathe cross slide in my workshop which I am considering to use and make an adapter to mount it as an object carrier to facilitate measurements.

Cheers

Dushan
 

technitype

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These tools are offered for sale on Ebay from time to time. Just search for the word "feintaster".

I saw one recently on Ebay for about $300.00.
 

Dushan Grujich

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These tools are offered for sale on Ebay from time to time. Just search for the word "feintaster".


I saw one recently on Ebay for about $300.00.
G'Day!

That is much too high. They can be bought for as low as EUR 50 to 80.

Cheers

Dushan
 

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