The Survey of Antique Fractional Gage Blocks

I'm still new to all the different aspects of machining, especially metrology. So Mike antique set of blocks made me dive the rabbit hole and when I searched "fractional gauge blocks" this came up: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4654600/

Basically laying out how gauge blocks are old "zombie technology". Many things were mention including wringing. Although I'd heard it mentioned like when Mr.Pete put together a stack for making precision angles for a sine gauge it was taken for granted and I never looked further. In the zombie tech article it makes it pretty clear that the ability to wring is crucial to proper use of gage blocks which of course I didn't know. I also didn't know that wringing isn't completely understood as I just assumed it was like vacuum developing between two flat surfaces but it still works in a vacuum!

I've toyed several times with buying a set of blocks for checking and measuring but was always stuck between buying old name sets that were often in not that great of shape and missing blocks for 4x's what a new set from Shars would cost. But after that article I can see it would have been a blunder as corroded blocks won't wring.

This is not to demean your score Mike as it's useful art, it is sharing what your survey has led me to in further understanding.
 
C-Bag said:
I'm still new to all the different aspects of machining, especially metrology. So Mike antique set of blocks made me dive the rabbit hole and when I searched "fractional gauge blocks" this came up: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4654600/

Basically laying out how gauge blocks are old "zombie technology". Many things were mention including wringing. Although I'd heard it mentioned like when Mr.Pete put together a stack for making precision angles for a sine gauge it was taken for granted and I never looked further. In the zombie tech article it makes it pretty clear that the ability to wring is crucial to proper use of gage blocks which of course I didn't know. I also didn't know that wringing isn't completely understood as I just assumed it was like vacuum developing between two flat surfaces but it still works in a vacuum!

I've toyed several times with buying a set of blocks for checking and measuring but was always stuck between buying old name sets that were often in not that great of shape and missing blocks for 4x's what a new set from Shars would cost. But after that article I can see it would have been a blunder as corroded blocks won't wring.

This is not to demean your score Mike as it's useful art, it is sharing what your survey has led me to in further understanding.
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An interesting paper.
From a hobbyist or small shop standpoint, I don't believe that gage blocks are a dying technology. One of the issues with making accurate parts is that there is a method of verification of the accuracy of our metrology instrumentss. A common practice requires that a calibration standard have an order of ten times better accuracy than the device being calibrated. At the bare minimum, an order of three times better accuracy. The most accurate device that most of us has in the shop for measuring length is the micrometer, typically with a resolution of .0001". For internal verification and/or calibration of a micrometer, a gage block set makes a convenient and economical calibration standard.

Working for an ISO certified manufacturer requires that all instruments, the use of which affect manufacturing quality, be calibrated by methods traceable to NIST. This usually means sending the instruments to a certified metrology lab. This is typically not the case for the small shop or the hobbyist. We just need to calibrate our instruments to our own satisfaction. Calibration of a micrometer to .0001" allows it to be used to calibrate our calipers, DRO's, etc. with confidence.
 
I agree RJ. I was as usual dragging on but came to the same conclusion. I still need a way to calibrate and gauge blocks are still useful to me. But like so many things in the thread it was surprising to find out that it was seen as zombie tech. I am still hesitant about exactly what to buy. Can I ask what you have?
 
I had good luck at auctions. Gage blocks are one of those things a business would buy new so they’re left for the pickings cheap. I had gotten lucky at one and got five sets in one bid. Two do-all sets and two mitutoyo sets one blocks and one set is round with a tapped center hole then a large set of brown and sharpe. The two do-all’s looked like they were used in the shop missing one and three blocks. The B&S and the mitutoyo were mint either use in inspection or sat on the shelf. I might have paid a hundred bucks for them. I just remember it was the opening bid and no one else bid on them. I was happy I got way more than I’ll ever need for less than some junk now days. Name brand sets can definately ring up some Benjamin’s.
 
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