Application Note

Using the Plan Wheel on Metric Plans

The Federal Metrication Program requires the use of metric dimensions and scale factors on all plans for certain federal projects. Using the PlanWheel to make measurements on those metric drawings is easy.

First, set the PlanWheel scale factor to match the print. The scale, if done in correct metric format, will look like 1: 50 or 1: 100, etc. (You will find all common metric scale factors in the PlanWheel Group 1, 2 and 3 scale factors.)

After you set the correct scale factor, set the PlanWheel to read out in the units you prefer. This need not be meters; you may read out in feet if you prefer. It's that simple!

Notes:

1. If you are used to working with U.S. scales, you will notice that the metric scales do not include the units of measurement. Where you may be used to ¼" equals one foot, or one inch equals ten feet, the metric scales are just 1:100. This means the actual project is 100 times bigger than it looks on the drawing. (You could look at it as one centimeter on the drawing is actually 100 centimeters of the project.) You do not need to worry about units, however. Just set the scale factor to match the plan.

2. The Plan Wheel can be set to read in U.S. standard units (MI, YDS, FT, IN) only, or in metric units (CM, M, and KM) only, or in both U.S. standard and metric units. The metric scale factors, however, are always available regardless of the PlanWheel units.

To change the units mode, hold down CLEAR and, at the same time, press UNITS. Repeat until you find the correct set of units. Then let up CLEAR. (For more information, refer to the instructions that came with the PlanWheel.)

3. If, after rolling a measurement, you wish to convert into another readout, say from feet to meters, simply press UNITS until you reach the desired readout.