======Etalon 12" Dual Beam Dial Height Gauge======

This is a Yellow Level Tool and is unlocked by Metal Shop Orientation.

This instrument is typically used on the [[surface_plate|Surface Plate]]. It can be used to scribe horizontal layout lines on workpieces, as well as measuring the height of features relative to the surface plate (or to other features)

====General====
  * Ensure the base of the instrument is clean before placing it on the surface plate.
  * The dial on the instrument reads in thousandths of an inch (1 division = 0.001", 1 rotation = 0.100")
  * The mechanical digital counters read in whole inches on the left of the decimal, and tenths of an inch on the right (one hundred thousandths)
  * The upper counter reads upwards, the bottom counter reads downwards. 

====Scribing====
  * Attach the scriber to the bottom of the gauge arm, using the clamp.
  * Zero the instrument
    * Using the handwheel, wind the gauge downwards until the scriber //just// touches the surface plate.
    * Press the reset button for the upper mechanical digital counter.
    * Turn the face of the dial until the pointer reads Zero.
  * Using the handwheel, crank the gauge upwards to the desired height.
  * Holding the instrument by the base, gently (but firmly) drag the scriber across the workpiece.

====Measuring====
  * Attach an indicator to the gauge arm, using the indicator adapter with the appropriate snug.
  * Zero the indicator.
    * Using the handwheel, wind the gauge downward until the attached indicator has some preload.
    * Turn the face of the indicator dial until the pointer reads Zero.
  * Zero the height gauge.
    * Press the reset button for the upper mechanical digital counter.
    * Turn the face of the height gauge dial until the pointer reads Zero.
  * Using the handwheel, wind the gauge upwards until the probe of the attached indicator is clear of the feature to be measured.
  * Holding the instrument by the base, move the indicator over the feature to be measured.
  * Wind the height gauge down onto the feature until the attached indicator reads Zero
  * The reading from the mechanical digital counter, and the dial on the height gauge, is the height of the measured feature.