Help! New collet, but bits are slipping out?

[daniel]

Hey guys, I'm cutting cabinet grade plywood and my bits seem to slip out after cutting awhile. It happens with both up and down spirals. I'm using a brand new collet from makita and its still happeining. I have a Makita 2.5hp on my bot. I listen to the machine, and as soon as the cuts start to sound deeper I stop the machine and check the bit. It's slipped everytime. I loosen the collet which is still tight. Push the bit back up, rezero and cut again. It now does it with a new collet and new bits. The only thing that hasn't changed is the plywood I'm cutting.
Any Ideas?

[billp]

Daniel,
Have you mic'd each bit? It COULD be the collet, but in many cases router bits aren't REALLY what they are advertised to be...

[daniel]

Good suggestion Bill. I just mic'ed it. I have a nice micrometer and it came up .25. I guess the nest step is to wait and see how the bits do in a different wood. Maybe its possible that my speeds are incorrect. I'm cutting at a depth of .2" at 1.5 ips with a router speed between 16 and 17 thousand rpm.

[rb99]

Get a new collet. Can you get one that is better than the one you are using?

RB

[gabepari]

Do you blow out the collet when changing bits. All the dust that accumulates between the slots can keep the collet from tightening down all the way.

Just a thought.

Gabe

[daniel]

Richard, I purchased the collet from Makita, The manufacturer....Gabe, Brand new collet, and brand new bit straight out of the packaging...Maybe the new collet is defective?

[scottcox]

Daniel,

I have to ask. Are you snapping the collet into the collet nut first?

Bill Young posted a video of this simple but crucial technique here.

[sailfl]

If you are snapping the collet in and you are blowing the dust out, try a new bit from another manufacturer. If there is still a problem, you may have a bad collet. They do make mistakes and they can not quality control every collet. Call the home office and talk with a tech person and get them to replace it.

[zeykr]

I'm not sure about the Makita router, but isn't it like the porter cables where the collet and nut are a one piece assembly so you don't snap one into the other?

[kubotaman]

Make sure you are not bottoming out the bit in the shaft. Push the bit all the way in the collet and then be sure to pull it out at least 1/8". The collet will not tighten on the bit it it is bottomed out to the shaft.