Watch Those Jaw Numbers

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Must do dumb things....
Feb 26, 2011
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I was working on a rod gland for a steam engine I'm working on. Several parts are round plates with a six hole bolt circle. I used my 4" Chinese rotary table in the mill to drill the parts.

The rotary table has replaceable inner and outer jaws. The jaws are "labeled" 1, 2, and 3 for their relative positions in the chuck. So as I replaced the inner jaws with the outer jaws, I thought I found the identification number and inserted them correctly into the chuck.

Well..... NOPE!

My bolt circle is off center. Take this little story as a parable about checking jaw positions. (After the screw up, I punched much more readable numbers into the jaws).


It's not the end of the world. I can redrill the holes and use the part as intended without any other issue. The screw up will be hidden on the final engine.


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