# Bit moves from collet nut



## mertenj (Oct 24, 2005)

I have a craftsman router model 315.174921. I have not used it heavily and am an occasional weekend woodworker. I ent to cut some dados in a plywood panel today and found that after extensive testing to make sure my settings were correct, the bit moved away from the collet and the dado was now the wrong size.

What caused this? How do I fix it?


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## reible (Sep 10, 2004)

Hi, 

Welcome to the forum!

I have several craftsman routers.... but not that model. Some craftsman routers have what seems to be a self-adjusting problem. I don't recall the model numbers so I can not tell you if yours has been known to have this problem.

What you will need to figure out is what is moving.... the height adjustment or the bit in the chuck. 

If the bit was a new one did you clean it off.... some bits have a coating to keep them from rusting.... that needs to come off.

The chuck needs to be clean and free of burrs or damage.... inspect and clean.... one trick I use is to a cotton swab to wipe around the chuck... if a burr is there the cotton will catch on it and some will pull off.

Like wise the bit needs to be burr free and clean.

The bit needs to be deep enough in the chuck (one method is to insert it as deep as it will go then pull out 1/16 to 1/8"), it needs to tighten, shall we say very tight. Some bits maybe undersized.... or have other defects that make them hard to use. Or the chuck might be damaged.... Sears chucks are normal cheap for those style routers maybe a $3 or so but then there is postage.....

To see if the bit is moving measure from the chuck to the tip of the bit and then do some routing and re-measure..... any movement should show up.

To eliminate the height adjustment issue use a warp of duct tape around the body then do some more routing and see if the depth changes.... take the duct tape off and try again.....

Now my guess is the cuts got to deep right? Cut some stock the width of the dado and as deep as necessary so it doesn't come above the flat surface. Now glue those pieces in place after the glue has dried make a new dado.

Hope this gets you started,

Ed


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## kp91 (Sep 10, 2004)

Ed,

Like the tip about using a Q-tip to find burs. That's a new one to me!


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## Erich (Sep 2, 2005)

Hi,
I have a 315 also and wonder if you have a phillips screw in the base of the collet as I do in mine. The purpose of that screw is to hold the 1/4 inch collet down tight and if it is loose it will change the depth of your router bit. Hope this helps. Delta


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## template tom (Sep 18, 2004)

mertenj said:


> I have a craftsman router model 315.174921. I have not used it heavily and am an occasional weekend woodworker. I ent to cut some dados in a plywood panel today and found that after extensive testing to make sure my settings were correct, the bit moved away from the collet and the dado was now the wrong size.
> 
> What caused this? How do I fix it?


If the bit is workig loose there is a good chance you may have a sixmm cutter fitted to a 1/4" chuck
Tom


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