4Grip collets offer better cutter grip for lower noise levels and increased cutter life.
These collets require greater clamping force, as they are more rigid and therefore MUST only be used in conjunction with ball bearing nuts.
Tool life and cutter performance are greatly influenced by the fit and rigidity of the cutter in the toolholder. This, in turn, is totally dependent on the collet.
It follows therefore that as much of the collet as possible should be in contact with the cutter. On standard collets there can be as many as 16 slits in the collet to allow compression and, therefore, a large proportion of the circumference of the cutter is not in contact with the collet.
Wealden 4Grip collets have a maximum of 8 slits, ensuring that the ratio of slit area to collet area on the circumference of the cutter is greater. This is particularly important on smaller diameter cutters, as the slit area will be a much greater percentage of the cutting tool shank. This increased grip will be noticed especially in a significant reduction in noise levels whilst cutting.
The downside of a more rigid collet is the need for greater clamping force when tightening. For this reason, 4Grip collets MUST
only be used in conjunction with ball bearing nuts.X