Basic rules of dressing
To achieve a superior surface finish and high material removal rates, it is of paramount importance to work with SMALL amounts of infeed ad (depth of cut) (0.002 to 0.01 mm; 0.00008 to 0.0004 inch) per dressing pass. In order to increase the wheel's surface roughness, increase the traverse velocity vd rather than increasing the depth of dressing cut ad. Higher traverse velocity vd equals higher wheel surface roughness and a more free-cutting, aggressive grinding wheel. Inversely, reduced traverse velocity vd equals a smoother wheel surface roughness and an improved surface finish on the workpiece but lower material removal ratesduring grinding.
IMPORTANT!
- Always apply grinding fluid when dressing. Dressing diamonds are very heat-sensitive and can be destroyed by excessive heat generation. Apply fluid right from the start of the dressing operation before the diamond gets heated. Intermittent application of grinding fluid may lead to heat-cracking of the diamond.
- Never traverse the grinding wheel without any depth of cut (ad = 0 mm). Use amin. depth of dressing cut
of 0.002 to 0.005 (0.00008 to 0.0002 inch). Without any depth of cut the CBN grit would be blunted, the
CBN grinding wheel would lose its cutting ability and lead to burning.
Wheel peripheral (surface) speed during dressing
If possible, use the finaloperating surface speed when dressing the grinding wheel.
Depth of cut ad
Select a range from 0.002 to a maximum of 0.01 mm (0.00008 to 0.0004 inch).
Traverse dressing feed rate vd
As a guideline use 150 to 300 mm/min (6 to 12 inch/min) feed rates. The feed rates depend, of course, on the wheel's rpm, and therefore, feed rates are more accurately expressed in mm per 1 revolution of the wheel:
0.005 to 0.025 mm (0.0002 to 0.001 inch).
Selection of dressing tools
Preferably choose rotary dressing tools. Use the following list in descending order of priority:
1. Diamond profile rolls or diamond form dressing disks
2. Truing brake
3. M CD blade dressing tools
4. Multi-point dressers
5. Grinding into mild steel
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