HAMAR LASER STEALTH Series, General Training Manual

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104
Three-Point Buck-In Procedure Using Multiple Targets
This method requires three A-
517 Targets and three readouts.
The procedure is basically the
same as with one target but saves
the time required to move a
single target to the three different
footprints.
1. Zero all three targets on the
near footprint.
2. Place two of the targets on the
other two footprints.
3. Tilt or aim the laser until all
three readouts read the same
numbers and the same sign.
4. When all three readouts read the same,
the laser plane is then parallel to all three
points.
5. It is best to have the numbers on the
three readouts less than .025. If they are
greater than .025, re-zero all three
targets on the near footprint and repeat
this procedure.
Two-Point Buck-In (Straightness)
A laser beam is often used as a "straight edge" to measure straightness. Examples are machine tool ways
or bore straightness measurement. The laser beam must be adjusted to be parallel to or coincident with an
edge or centerline. The process of making that adjustment is called "bucking in."
Two points in space define a unique straight line; therefore, two reference points are needed in order to
relate the position of a laser beam to a surface or centerline. Any two points may be chosen (the suitability
of the points cannot be judged until after the measurement has been done). The points are usually selected
near the extreme ends of the job for the sake of convenience. A Two Point Buck-In makes the laser beam
parallel with these two points.
The Two-Point Buck-In procedure is most commonly performed using an A-517 Single Axis Target and a
scanning laser.
If you are using a
straight line laser you will need a two-axis target on a T-230 x and y
adjustable stand. The procedure will be the same, but you must also adjust the horizontal readings to zero.
On the near point, adjust the target micrometer, and on the far point, aim the laser with the azimuth
adjustments.
Two Point Buck-In Procedure
1. Place the laser in a position that is as close to the near target position as possible.
Orient the laser so that either the long axis of the base or the short axis of the base is parallel to the
near and the far target positions.
2. Adjust the target micrometer until the readout reads zero.
3. Move the target to a far position and aim the laser using the adjustment micrometers until the
readout reads zero.
4. Move the target back to the near position and adjust target again until the readout reads zero.
Figure 50 – Three-Point Buck-in Using Three Targets (Recommended Setup)