 |
Problem:
|
Short tool life and
poor performance of 1/4" and smaller carbide tools. ER collets
1/4" and smaller fail to provide consistent T.I.R. and high
rigidity, thus increasing tool wear and driving up cost.
|
| Reasons: |
| 1. |
ER Collets 1/4" and smaller allow
40% of the collet to extend out of the collet pocket. This means 40%
of the jaws surface area does not properly collapse on the tool shank
because they are unsupported by the walls of the pocket. |
| 2. |
Because so much of the collet is out
of the pocket, when the ER nut contacts the shoulder of the collet,
friction causes it to twist the jaws of the collet during tightening.
This distorts the collet axis in the pocket, contributing to inconsistent
T.I.R. (Refer to the diagram to see how DNA nut does not contact the
collet shoulder.) |
| 3. |
On ER collets 6mm diameter and smaller,
the small jaws do not provide the holding force and rigidity on the
shank necessary to produce acceptable T.I.R. |
