- Joined
- Sep 11, 2014
- Messages
- 76
You know, the distance between point A and point B are the same no matter what ruler you use. I don't know why a meter,
"The metre (BIPM spelling), or meter (American spelling), (SI unit symbol: m), is the fundamental unit of length (SI dimension symbol: L) in the International System of Units (SI).[SUP][1][/SUP] Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it has been defined as "the length of the path travelled by light in vacuum during a time interval of 1/299,792,458 of a second.",
is a better measurement than a yard. but the modern definition of a yard is based on the meter.
I am accustomed to working with imperial measurements while my lathe lead screw and change gears are metric and the dials imperial, go figure. This explains why the last division on the dial was a different size, I just thought it was poorly made. I recently needed to make a metric part, so I converted to imperial and built it. You should use what you are comfortable with, its all the same.
Caster
EDIT: Interesting observation, was an inch prior to 1959 a different size than an inch today? Has anyone made a replacement part using pre 1959 specs and not have the part fit?
"The metre (BIPM spelling), or meter (American spelling), (SI unit symbol: m), is the fundamental unit of length (SI dimension symbol: L) in the International System of Units (SI).[SUP][1][/SUP] Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it has been defined as "the length of the path travelled by light in vacuum during a time interval of 1/299,792,458 of a second.",
is a better measurement than a yard. but the modern definition of a yard is based on the meter.
"Traditional standards for the exact length of an inch have varied in the past, but since July 1959 when the international yard was defined as 0.9144 metres, the international inch has been exactly 25.4 mm. "
I am accustomed to working with imperial measurements while my lathe lead screw and change gears are metric and the dials imperial, go figure. This explains why the last division on the dial was a different size, I just thought it was poorly made. I recently needed to make a metric part, so I converted to imperial and built it. You should use what you are comfortable with, its all the same.
Caster
EDIT: Interesting observation, was an inch prior to 1959 a different size than an inch today? Has anyone made a replacement part using pre 1959 specs and not have the part fit?
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