The amount and size of fine woody debris found on the floor of a forest is an indicator of fire risk. Fine woody debris is measured along a line and recorded in size intervals. These are grouped into .5, 1, 3, 5 and 7 cm diameters categories. A gauge with these sizes cut into the edge of the material makes the task of measurement much quicker, more accurate and simpler. These are called Go-Nogo Gauges.
Step 1: Select Material
Select a material that is durable such as aluminum or puckboard. For this example I have used 1/8 inch Al plate.
Step 2: Measure
Measure out each of the of the opening categories carefully, and scribe the sizes on the material.
Step 3: Cut and File
Cut the openings with a bandsaw staying on the waste side of the scribed lines.
File to the scribed marks. Check opening sizes with a standard measure.
Step 4: Add a Hole
Make a hole in the gauge for a line that can be fastened and place a piece of flagging tape so that the gauge can be easily seen.