With the exception of the ball-end cutters, all types have eccentric relief on the cutting lip (see figure below). This type of clearance gives a stronger edge compared to a conventionally ground end cutter with two clearance faces. When this type of relief is ground, the grinding wheel must be tilted or dressed at an angle according to the figure and formula below.
All Dormer carbide milling cutters with TiCN and TiAlN-X coatings should be recoated after regrinding in order to give the same performance as a new tool. On end mills, the most important layer is on the clearance side which means that if the cutter is not seriously damaged after use, the regrinding can be carried out on the rake side only, without recoating. The service life can then be estimated at about 80% of a new tool.
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Table showing Cutter Geometries
| Article No. | Diameter mm | Rake angle
Main edge | Relief angle
Main edge | Primary relief
End teeth | Secondary relief
End teeth | Relief to centre |
| S200, S201, S241, S271, S275, S276 |  | 9-12° | 8-10° | 6-7º | 15-18º | 1-2º |
| S100, S102, S300, S302 | | 9-12° | 8-10° | 6-8º | 25-28º | 2-3º |
| S120, S122, S124, S125, S126, S128, S308, S310, S311, S312, S320, S322, S326, S327, S330 | | 9-12° | 8-10° | 6-8º | 25-28º | 1-2º |
| | | | | |
| S281 | | 9-12° | 9-11° | - | - | 1-2º |
| S500, S501, S510, S511 | Ø2 - Ø3 | 9-12° | 19-21° | 15-17º | 24-26º | - |
| Ø4 - Ø8 | 9-12° | 13-15° | 13-15º | 24-26º | - |
| Ø9 - Ø20 | 9-12° | 11-13° | 11-13º | 19-21º | - |
| S502, S503, S522, S532 | Ø2 - Ø3 | 0-3° | 19-21° | 15-17º | 24-26º | - |
| Ø4 - Ø8 | 0-3° | 13-15° | 13-15º | 24-26º | - |
| Ø9 - Ø20 | 0-3° | 11-13° | 11-13º | 19-21º | - |
| S282 | | -7/-10° | 8-10° | 6-8º | - | 1-2º |
| S290 | | 0-3° | 8-10° | 10-13º | 25-28º | 1-2º corner radius |
| S306 | | 4-6° | 8-10° | 6-8º | - | 1-2º |
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Article No. S100, S102, S300, S326, S327
| Diameter mm | Corner chamfer
|
| 2 - 4.8 | 0.10 x 45º |
| 5 - 8.7 | 0.15 x 45º |
| 8.75 - 19.7 | 0.25 x 45º |
| 19.75 - 20 | 0.35 x 45º |
| | S306, S312
| Diameter mm | Corner chamfer | Helix reduction max. A mm |
| 2 - 3.75 | | |
| 3.8 - 8 | 0.15 x 45º | 0.35 |
| 8.1 - 12 | 0.15 x 45º | 0.35 |
| > 12 | 0.20 x 45º | 0.50 |
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