Thread: But we did agree to disagree

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.02 ends because there is only an expected 0 for infinity
.020 """ """ """ """ _______________________""""""""" etc
they are the same measure ..
when you make it .021111111111111 then it is not the same measure as
.0209999999999999...

In my GE machining history a long time ago and then my design positions - our design practices said .02 meant .020, .0200 or .02000 or for as long as you wanted to add zeros to the end. There was no tolerance implied. If there was a tolerance, it was either stated in the title box on the front of the drawing (usually another drawing, called a spec) or at the specific dimension itself if it deviated from the spec drawing allowance. It didn't mean .021, .022, .0201 or any other dim.

Many companies have design practices that deviate from this and do allow you to make assumptions - but you sure don't have that luxury on a 43 inch long staem turbine blade or 100,000 pound (plus) shaft that rotates as high as 5000 rpm or more. If you can find a copy of Machinery's Handbook, my newest is the 21st edition(old), there are about 50 pages of a chapter, Allowances and Tolerances, and another 10 of measuring instruments that are guaranteed to induce sleep.