On Tuesday, 17 Dec 1996, Dave Williams wrote:
> -> T-gauges are neat, and a whole lot more accurate than one might
> -> think, but they can be fooled.
>
> I have a two-point dial bore guage. The old T-guages are actually
> easier to use.
Oh, my, yes.
> -> They only measure at two points, and you can
> -> miss an out-of round condition.
>
> How else are you going to find an out-of-round condition? You turn the
> guage 45 or 90 degrees and measure that way. The difference tells you
> out of round.
If the OOR condition is oval (two-lobe) as typical in a car cylinder. If
it is three- or five-lobed as from a twist drill, you may never see it
with a two-point measuring device. That's when you need that three-point
bore gauge or a radial indicator setup.
Phil
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