At least as many of its surfaces should be trued as are necessary for the "lay out."
After the boring is completed the edge E is trued by the large-face milling cutter M bolted to the spindle sleeve.
When these surfaces have been trued up carefully, remove the piece from the vise and saw the pattern from it.
After the corner has been soldered and the box pickled, it is again placed over a block and trued up square.
If the face is somewhat irregular, it can be trued up by placing it on a block of wood and going over it with a rawhide hammer.
This will give the general shape of the bowl which may be trued up later by sawing and filing.
The invert was trued up by drawing along the runners a semi-circular templet having a radius of 21½ ins.
Straight-edges are sometimes made of cast steel and trued on both edges.
Smoothing planes are, as the name implies, used to simply smoothen the work surface after it has been trued.
The surplus metal on the top end is now cut off and trued up.