> "T" gauges and inside micrometers measure only two points, or a simple
> diameter. If you have three-lobe or five-lobe out-of-roundness,
> you can miss
> it using these tools.
Well perhaps, except the same thing is true of a dial bore gage. It
measures 3 points, so if you're on the peaks of a 3-lobe, you could still
miss it.
But, engine cylinders wear into ovals, with the axis of the oval across the
crankshaft (where the piston skirt touches the bore). Making two
measurements at right angles with a two-point gage will tell you both the
oversize, and the ovality, directly. Even with a dial gage, you still have
to make both measurements.
Randall
/// triumphs@autox.team.net mailing list
/// To unsubscribe send a plain text message to majordomo@autox.team.net
/// with nothing in it but
///
/// unsubscribe triumphs
///
/// or try http://www.team.net/cgi-bin/majorcool
|