I am having troubles with bits sliding out of my pc router on my cnc. Anyone having this problem. did it on .25" and .5" chucks so i am thinking it might be bit type or speeds.

Make sure it's clean (almost surgically - every parts of the chuck, collet parts and bit shank) and that it's tight. Does it happen with every bit or just some?... measure the problem tools with caliper.

Does that help?

I will try cleaning collet but it happend with two different collets on different bits so i think it might be something else. has anyone upgraded to the er16?

1) make sure the bit is not bottomed out in the collet. If it bottoms out, pull it back out about 1/4" before tightening.

2) If the bit was not bottomed out, it just wasn't tight enough.

I've got 4 Porter Cable routers and have never had a bit come loose. When tightening the collet, place the two wrenches close together so you can squeeze them with both hands to tighten.

A cheap sh!t collet and nose will allow the tools to worm their way out if you push them hard, and certain harmonics induced during the cut can accelerate this effect. This is because the garbage collets used on ordinary power tools only pinch the tool a wee bit around one annulus at the front of the nut. Thus, any slack on the shank, or the back end of the collet allows that end to precess and wobble around inside the spindle nose. This allows it to worm its way out under load.

An ER16 is quite a bit more solid, much better gripping force. But, you've then got to figure a way to retain the collet adapter securely.

I'm going to take a stab at this and guess you were using solid carbide highly polished bits? Gerry I have had up to 5 Porter Cable 3.25hp routers and they all threw bits. Maybe it was the material I was cutting, bit selection etc, but I simply could not keep them in the collets. My solution was to red loctite them in. Never had one to slip after the loctite. I do however have to clean the bit and the collet when making a change and it is a mess.

Mike

This works on big chuck jaws holding hard material with same problem.

Get a small piece of carbide, a 12v DC plugpack (that won't blow up if overloaded.)

Put a 1000uF electolytic capacitor across the output (observe polarity)

Now connect one side to the collet, and the other side to the piece of carbide held in a clip or whatever.

Spark it up and down lots all over the the holding surfaces.
It will become embedded with microscopic bits of carbide.

Now you can hold really hard things because the jaws will key into the surface!
Find some tool steel and other bits of hard stuff to practice on and look at the surface with a magnifying glass. You'll see when it's working.

Put a 20 or 30w 12v light globe between the power pack and the elctrolytic to limit the current.:devious:

By jove, Neil, I think you've invented the Rocklinizer :D

By jove, Neil, I think you've invented the Rocklinizer :D

Now it is even simpler.
Just rough up the cutter/router/drill shaft using this process.
May have to replace collets ocasionally, but if tight and true they WILL NOT SLIP!

:idea::cheers: