Datum references

From Wikipedia, the free encyclopedia

Datum references refers to the 2 straight edges on a workpiece (wood, plastic or metal). For metal and plastics workpieces, the datum reference is called "datum edge". The First datum edge is marked with a slanted line (/) and the second is marked with 2 parallel slanted lines (//). Datum references on a wooden workpiece are called face side and face edge. These are marked with a pencil. The datum references of the materials are to be checked for squareness (90 degrees on the edge). If the edges are not square, they will need to be planed or files until they are as described with these following steps:

1. Plane the face side, check for flatness using a metal rule
2. Mark the face side accordingly
3. Plane the face edge, check for squareness using the tri-square
4. Mark the face edge accordingly

The straightness of an edge can be checked using a steel rule.