7. Accuracy Check
Before starting any critical work, check your laser for accuracy.
1. Plumb Point Accuracy
NOTE: This test should be done indoors with dim lighting. It is
critical that the laser mark is easily seen.
1.
Position laser at Point 1, 10' from a
doorway.
2. Mark beam at Point 1.
3. Mark beam at Point 2, 20' away.
4. Mark Points C on the floor under
doorway and D on doorway.
5. Move laser near Point 2. Aim the beam
through Points 2, C, and 1. Mark Point
E next to D on doorway.
6. If the distance D to E <1/16" for a 10'
doorway, your plumb accuracy is
within specification. (Figure 14)
16
Figure 14
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