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©2014 Johnson Level & Tool - Rev. 1
Calibrating Vials
To access the calibration screws remove the stickers located to the
right and left of the vial at the top of the unit. First, adjust the
calibration screws to move the bubble back to center taking out half
of the error in the vial. Rotate the level 180° on the same gauging
edge and move the bubble to center. Repeat this process until the
error is entirely removed and the bubble stays in the center. Plumb
vial and 45° vial cannot be calibrated.
Checking Laser
Once the vials are accurate, laser accuracy can be verified (near tar-
get, far target method). Start by placing the unit on a flat surface and
aim the laser at a stationary target. Position the unit/target at close
range and note a reference point on the target. As the unit is moved
away from the target, such that alignment of the laser to the target is
fixed, and the only variable is distance, the accuracy of the laser can
be verified/calibrated.
Calibrating Laser
There are set screws on the side and bottom of the unit that provide
calibration for the laser.
For vertical calibration, use underside screws, tightening the front
screw to adjust up and tighten the rear to adjust down.
For horizontal calibration, use two screws on the side of the part
number and date code. Tighten the front screw to adjust right.
Tighten the back screw to adjust left.
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