Vernier Height Gage

The accuracy of the finished workpiece is generally determined by the accuracy of the layout;therefore great care must be used when laying out. To make a precision layout, a person must beable to read and understand drawings, select and use the proper layout tools for the job, andaccurately transfer measurements from the drawing to the work piece.

The vernier height gage may be used to measure or markwork off vertical distances to + or - .001 inch (.02 mm)accuracy. The main parts of the vernier height gage (Fig. 21-2) are the base, beam, vernier slide, and scriber, which isattached to the vernier slide when marking layout lines.

Other accessories, such as a dial indicator or depth gageattachment, may be added to the slide for measurement andinspection work.

The graduations on the beam and the vernier slide are thesame as those on a vernier caliper and the readings are madein the same manner as the with the vernier caliper.

When hole locations and dimension lines are made on alayout, they are generally made from two machined edges

called reference surfaces using X and Y coordinates. Anylayout composed of holes, angles, and lines may becalculated using trigonometry to determine the coordinatemeasurements.

The vernier height gage is a delicate and highly sensitivemeasuring instrument.

- Handle with Care

- Always be sure the bottom is clean

- Be sure the table top is also clean

- Pull the height gage along the work. Do not push it.

Layout Table

Layout work may be performed on a layout table. These canbe made from granite or cast-iron. However Granite layouttables are considered to be better then cast-iron type becausethey:

- Do not become burred

- Do not rust

- Are not affected by temperature

- Very stable compared to cast-iron. - (No internal stress, this eliminates warping and

distorting).