Page 282 - Mechanical Engineer's Data Handbook

270 MECHANICAL ENGINEER'S DATA HANDBOOK

7.2 Angle measurement

1.2. I Combination angle slip gauges Internal taper (using two balls)

Precision angle blocks are available with faces inclined
to one another at a particular angle accurate to one
second of arc. The puges may be wrung together as
with slip gauges, and angles may be added or subtrac-
ted to give the required angle. Details of a 13-block set
are given.
13-Block st:
Degrees: 1,. 3,9,9, 27,41.
Minutes: 1, 3,9, 27.
Seconds: 3,9, 27.
Plus 1 square block.

I

7.2.3 Sine bar
1.2.2 Measurement of angie of tapered
bores This is used to measure the angle of one surface relative
to another. It consistsof a precision bar with rollers, a
precise distance apart. The angle of tilt is determined
The method of measuring the angle of internal and
external bore tapers is shown using precision balls, from the size of slip gauge used.
rollers and slip gauges.
Angle of surface 6 =sin- (9
External taper (using rollers and slip gauges)
where: L = distance between rollers, h = height of slip
gauges.

Slip gauges