Machinist’s blocks, 0.5, 0.6, O.7 inch height, purpose?

I won a Kennedy box half-full, at auction. It had been owned by a master machinist who closed his shop. All the Starrett etc. instruments formerly in it were removed and sold separately, so most of remainder were shop-made tools. I have no idea what these blocks were for. I’ve cleaned the drawer and isolated the mystery blocks. There are four configurations of plan view but only three heights, namely very close to 0.500, 0.600, and 0.700 inches height. The side faces aren’t as well-finished as the possibly surface-ground tops and bottoms, so I didn’t bother measuring except one or two on the left which are like 1 x 1.25 inches.

So most of us are familiar with 1,2,3 and 2,4,6 blocks but are these something similar or what? I’m pretty sure they aren’t shop-made gauge blocks or he wouldn’t have had them kicking around with other hardened things in his K box. Anyone recognize these?

I think you just answered your own question "Shop made tools".

Cannonmn said:

View attachment 274701I won a Kennedy box half-full, at auction. It had been owned by a master machinist who closed his shop. All the Starrett etc. instruments formerly in it were removed and sold separately, so most of remainder were shop-made tools. I have no idea what these blocks were for. I’ve cleaned the drawer and isolated the mystery blocks. There are four configurations of plan view but only three heights, namely very close to 0.500, 0.600, and 0.700 inches height. The side faces aren’t as well-finished as the possibly surface-ground tops and bottoms, so I didn’t bother measuring except one or two on the left which are like 1 x 1.25 inches.

So most of us are familiar with 1,2,3 and 2,4,6 blocks but are these something similar or what? I’m pretty sure they aren’t shop-made gauge blocks or he wouldn’t have had them kicking around with other hardened things in his K box. Anyone recognize these? View attachment 274700

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height blocks (sometimes called chucking blocks) are use to support sides (vertical mill) when part in a mill vise so part is clamped on both ends of part.
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if part only clamped on right side of mill vise the left side of part can much more easily move when doing heavy milling. many parts are not simple rectangles and need a chucking block to better clamp both ends of the part in a mill vise. they dont need to be gage block high precision cause mill vise movable jaw can tilt/pivot a .001 or .002" over 6" usually
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if one side of part is wavy from being torch or plasma cut many use a piece of plywood or a tongue depressor or craft stick instead of steel chucking block. the movable vise jaw will compress and the wood will conform to wavy torch cut part shape but the wood will be permanently deformed so its usually a one time use
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custom size steel chucking blocks often are stored for particular parts by the hundreds sometimes thousands of sizes. but if in a vidmar cabinet drawer and sorted by size then often the same chucking block size can be used for many different parts instead a special chucking block only for one particular part

I think I read that a 5 6 7 triangle is also a right triangle just like the well known 3 4 5 triangle?
Bill D.

Bill D said:

I think I read that a 5 6 7 triangle is also a right triangle just like the well known 3 4 5 triangle?
Bill D.

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5 6 7 is not a right triangle. Pythagorean theorem.

CarlBoyd

Bill D said:

I think I read that a 5 6 7 triangle is also a right triangle just like the well known 3 4 5 triangle?
Bill D.

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Pythagoras says no. 3*3 + 4*4 = 25 = 5*5, but 5*5 + 6*6 = 61 != 49 = 7*7 .

If those blocks were in my toolbox, I'd be using them to support stuff up off the drillpress or mill tables when I needed to cut through holes or profile an edge.

Yes, just spacers used for set-ups. I have some lengths of flat ground stock that I use in a similar manner. I bought several lengths of it and cut them up into various lengths. Since I wanted four each of several lengths and one piece was not enough, I purchases a couple of pieces of each size. The two pieces differed by a thousandth or two so I marked the ones that came from the same piece of stock with notches on one corner: one notch for the first piece of that size and two notches for the second piece. That way I can match things up as close as possible when need be. These assortments of blocks have been useful many times and they were relatively cheap and easy to make.

I'd have expected 0.800 as well. In conjunction with 1-2-3 blocks that gives you 0.1 increments from 1" to 3.8". mMybe 0.900 too to close the gap.

Clive