Replies

1. 
   BG | Jan 20, 2005 06:06pm | #1

   Patrick,

   I had this issue about a year ago with a Whitesides upspiral bit and my DeWalt 621.  I swapped out the bit, DeWalt replace the collet...and its holding...but I don't use the bit.

    

1. 
   highfigh | Jan 20, 2005 06:14pm | #2

   There's another thread for the same problem here or in Tool Talk. Try installing the bit without bottoming out. Or, put it in, then after snugging the collet a bit, slide the bit out about 1/8"-3/16". Most bits have a fillet where the shank meets the head and if the fillet is in the collet, once the collet is tight(as much as it can be when it's clamping on the fillet instead of the shank), the torque acting on the bit when you start cutting is enough to loosen the bit.
   "I cut this piece four times and it's still too short."

2. 
   JohnWW | Jan 21, 2005 01:16am | #6

   Patrick,

   In general, unless the bit has spun badly in the collet, the shank won't wear out.  Collets however, do wear out with use, and may need to be replaced once in awhile.  When you replace the collet, it is a good idea to replace the nut at the same time since they wear out also. 

   Before the new collet is installed, check that the tapered bore in the spindle is smooth and burr free.  If needed, very lightly polish the bore with something like 600 grit emery paper moistened with a little oil.  If the bore is badly burred or pitted, or worn into a bell shape, the router has probably reached the end of its life since it usually isn't cost effective to replace the armature and shaft assembly.   

   The bore of the collet should be clean and grease free, but the outside tapered surface of the collet, and the top surface that the nut bears on, should get a bit of wax for lubrication.  The threads on the spindle nose and the nut should get a touch of light grease.  The wax and grease on the moving surfaces will allow the collet to wedge tighter and grip the shank of the bit with considerably more force.

   John W.

2. 
   UncleDunc | Jan 20, 2005 06:55pm | #3

   http://forums.taunton.com/tp-knots/messages/?msg=21125.1

3. 
   forestgirl | Jan 20, 2005 08:09pm | #4

   Good advice above, but the very first thing to do when a router bit slips is to take it out and make sure everything's clean -- the bit shaft, the collet.  Any little thing can interfere with the snugness of the collet. 

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
   Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

4. 
   Pondfish | Jan 20, 2005 11:38pm | #5

   1) be sure it is in very tight.

   2) for (1) to happen, all parts must be clean and oil-free.

   3) never, never bottom out a bit.

   4) The likelihood a bit will pull out is proportional to the force being applied to the bit.  If you are taking big bites with your bit, it will increase the possibility of it pulling out.

   5) ditto for a dull bit.  despite what bits cost, when you get a dull bit, throw it out.  Dull bits cost more in ruined work and nasty accidents than a new one costs.

   6) verbally threaten the bit before you start working with (5).

    

   ;-)

5. 
   ron61 | Jan 21, 2005 03:39am | #7

   The collect is shot and needs to be replaced. - If the bits moving  its spun and will get worse.