Plastic caliper wear out quickly. HC steal, and titanium do not. PLASTIC has gross temperature fluctuations. Single sheet cigarette cellophane, .001, or 1 mill, or one thousandths of an inch. A PLASTIC caliper will not yield the same measurement in a hot garage, & air conditioned house. A PLASTIC calipers “spindle tread” is 100 treads per inch. you would be lucky to keep that tolerance for more than 10 correct measurement.

Who cares right?

I have a few Paulson chips that I purchased this year. They miced out smaller than the tolerance band of plus or minus .001”. After more careful visual inspection, I discovered the cheque had been turned on a lath to picture a better condition than was advertised.

Who cares about a $20 cheque. What about a $2000.00 cheque. PLASTIC CALIPERS?