Replies

1. 
   Samson | Dec 31, 2007 06:18am | #1

   Forgive my ignorance, but what's the difference if your bit "bottoms out" ?  I pretty much only use my router as a plunge, so maybe it's a fixed base issue?

1. 
   mapleman | Dec 31, 2007 06:47am | #2

   Samson,

   Supposedly  if you let the bit bottom out there is a chance for the bit to work loose in the collet (some bits flare out just a hair where the shank meets the cutting part of the bit).  I think the collet holds much tighter if you pull the bit out just a tad. I use  1/4" and 1/2" O-rings on all of my bits to prevent them from bottoming out when tightening the bit in the collet.

   Lee

1. 
   saschafer | Dec 31, 2007 06:59am | #3

   But that's when the business end of the bit bottoms out against the top of the collet, not when the end of the shaft bottoms out at the bottom of the hole (which is what the space ball would prevent).

   -Steve

    

1. 
   mapleman | Dec 31, 2007 09:02am | #7

   Steve,

   You've got a point - I didn't think of it like that. All router bits do not have the same length shaft.

   Lee

1. 
   Disputantum | Dec 31, 2007 11:17am | #8

   I'd assumed that it was to prevent the shaft from getting cockeyed and not allowing the collet to fully tighten. But it's such a tight fit, I don't know if that's possible. Anyway, I've never had a problem with the bit staying put while I do the tightening. I push the bit all the way down and then pull it up a hair.ne sutor ultra crepidam

2. 
   forestgirl | Dec 31, 2007 07:20am | #4

   My understanding is that, since the bit expands with heat, dropping it in all the way to the bottom can cause problems when it gets hot, stresses the collet maybe?  Every router book or basic how-to article I've read mentions this.  I always drop mine in, get the collet almost-snug and tug the bit up just a smidge before tightening.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

   Edited 12/30/2007 11:21 pm by forestgirl

1. 
   Jimurock | Dec 31, 2007 07:38am | #6

   I thought and do likewise, but the (very brief) manual for my Triton says to make sure the bit is all the way in.  I don't but maybe should.  And I have a cheap no-name plunger for edging which seems to have some kind of spring in place to prevent bottoming out.  There's virtually no manual with that one.

   Jim

1. 
   BG | Dec 31, 2007 01:23pm | #10

   Jimrock,
   The Triton instruction "Triton says to make sure the bit is all the way in" relates to the !/4" adapter/insert....that goes into the 1/2" collet.

1. 
   Jimurock | Dec 31, 2007 09:05pm | #12

   Ooops.  That makes so much sense I won't even check it.  Thanks.  I knew speed-reading would get me in trouble some day!Jim

3. 
   MikeHennessy | Dec 31, 2007 03:42pm | #11

   A router collet works by moving the bit down into the shaft, allowing the taper on the collet to tighten the collar around the bit as it does so. If you restrict the ability of the bit to move down by, e.g., bottoming the bit, the collet can't perform as designed and the bit may not be held as tightly as you'd like. Then, as FG notes, when the bit heats up and expands, it may push the collar up/looser, so the problem is made even worse.

   The collets on my routers are all snug enough that it takes a bit of pushing to get the bits to move in them even when they are not tightned, so the bits aren't likely to inadvertantly bottom out. If the OP's collet is looser, I see no issue with using space balls, or similar, to avoid the issue.

   Mike HennessyPittsburgh, PA

2. 
   forestgirl | Dec 31, 2007 07:22am | #5

   I don't know what the diameter of a space-ball is, but it's probably more than the O-ring mentioned above, which would be my choice.  You don't need much space.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 
   
3. 
   dgreen | Dec 31, 2007 12:55pm | #9

   I thought it was because tightening the nut forced the collet and the shaft of the bit downwards, not leaving room for it to do so could result in bottoming out early resulting in the collet not getting fully tight.

   ------------------------------------

   It would indeed be a tragedy if the history of the human race proved to be nothing more than the story of an ape playing with a box of matches on a petrol dump. ~David Ormsby Gore