Kval 960-3, Operation And Service Manual

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Appendix: Router Collet Assembly Basics
KVAL Operation/Service Manual
3-16
Appendix: Router Collet Assembly Basics
A collet is the steel sleeve that holds a router bit in a router. The collet works with the router shaft
(connected directly to the motor) and the collet nut.Collets are machined to perfectly mate with
the tapered recess in the end of the shaft and to hold a router bit with just enough clearance to slip
the bit in and out when loose.
• For the best grip, a router bit should be fully inserted into the collet and then backed
out about å" (leaving between œ" and 1" of the shaft in the collet). The gap allows
the collet and bit to be pulled down as the nut is tightened. If the bit is bottomed out
in the shaft before tightening, the bit has nowhere to move and the collet won't
tighten properly.
• As with most tools, parts that have metal-to-metal contact, or are in contact with
dust and pitch, will wear over time or require maintenance. Worn, scratched, dirty or
out-of-round collets will not provide adequate holding power and can increase run-
out and vibration.
• To extend the life of your collet, never tighten a collet without a bit in place. This
can compress or deform the collet, leading to an improper fit on the bit.
Checking Collet Assembly
Pitch and dust can build up in and on the collet, as well as in the recess of the shaft and inside the
collet nut. A simple cleaning every so often will ensure a tight fit on the bit.
• Clean the collet parts with a dampened rag.
• Use a small brush with either nylon or brass bristles to reach into close areas. These
bristles will clean the collet without damaging the metal surfaces.
Collet Spindle
Collet
Nut
Verify that there is no damage or
bluing on the side of the collet