pat32rf
Veteran Member
My Dad, (first auto mechanic, then tech school teacher of same) had one that looked identical. His was an old unit back in the 60's...By the 70's we had electronic units at work for checking rpm..
I could do a different "what is it" thread every week
I could do a different "what is it" thread every week :laughing:
JB
KubotaSam got it!. I have the exact same item. It was supplied with different tips, but was made to read the RPM of any rotating shaft.
Yep! If you are measuring the speed of a 1" shaft or a 10" diameter flywheel attached to the same shaft, that tach is gonna give different readings. However, for multiple readings of similar shafts, the tach could be used with some accuracy as long as the rubber tip doesn't wear too much.
JB, that sure looks like it hasn't been used more than once or twice.
Jim,
The diameter doesn't matter, since it will only read from the dead center of whatever is spinning.
The tip is applied directly to the center, parallel to the shaft, not perpendicular. This tip is old and hard but could be easily replaced, and yeah it doesn't look like it saw much use, it's looks like a well made gauge, like everything else back then.
JB