Restoring the cutting action of the wheel
Dressing of Grinding Wheel The purpose of dressing is to restore the correct cutting action of the wheel. Dressing removes the clogs on the surface of the wheel and the blunt grains of the abrasive, exposing the new sharp abrasive grains of the wheel which can be cut and brought to shape efficiently.
Spot facing
The process of producing a flat seat for a bolt head at the opening of a drilled hole is called as Spot Facing.
Tolerance
Tolerance is defined as the difference between the maximum and the minimum sizes allowed in manufactured components.
1 mm
For a hole designated as 28 +/- 0.5 mm, the tolerance is 1 mm.
0 mm
Hole Basis System In hole basis system hole limit dimensions are considered constant and various types of fits are obtained by suitably varying the limit dimensions of the shaft.
In a hole basis system the lower deviation for the hole 'H' is zero.
