Bit Slipping

[aussie]

Hi All,

I have experienced a 0.25 EM slipping during a cut twice now...

The bit is located well within the collet, collet and nut cleaned between bit changes, I am taking small depth of cuts 0.125 or less.

Would appreciate any ideas why this is happening from time to time.

Thanks,

Ron

[gerry]

How old and what brand is the collet? Cheap collets are not always sized correctly. The can also be out of alignment. Also, measure the true diameter of the bit. It can be undersized. Precise Bits or Techniks collets are pretty inexpensive and good quality.

[aussie]

Apr 2, 2019 0:53:46 GMT -5 gerry said:

How old and what brand is the collet? Cheap collets are not always sized correctly. The can also be out of alignment. Also, measure the true diameter of the bit. It can be undersized. Precise Bits or Techniks collets are pretty inexpensive and good quality.

The collet and EM came from Axiom, which I believe is an Amana 46415 0.25EM part of AMS 133 Starter Kit.

I have had the AR 6 for about 6 months and is only hobby use.

Thanks for your reply

[johnb]

"Well within the collet"...the bit can be too deep in the collet. Is the collet grabbing on the flutes or the transition from shank to flute? If you have it bottomed in the collet, it won't grab the shank properly.

And another possibility...you're in Australia, right?  Is it possible that your collet is metric rather than inches?  That would be a mismatch with a 1/4" bit.

[aussie]

Apr 2, 2019 7:00:09 GMT -5 johnb said:

"Well within the collet"...the bit can be too deep in the collet. Is the collet grabbing on the flutes or the transition from shank to flute? If you have it bottomed in the collet, it won't grab the shank properly.

And another possibility...you're in Australia, right?  Is it possible that your collet is metric rather than inches?  That would be a mismatch with a 1/4" bit.

Yes that could be a possibility... will back off the depth of the bit and see how it goes.

I expect the collet supplied by Axiom would be imperial... shall ask the Distributor in Australia.

Thanks for your suggestions.

Ron

[traindriver]

I have had the bit slip out of my collet a few times in the three plus years I've had mine, so I resorted to tightening it really tight. About four months ago, we got a large cnc router where I work, and it has larger collets. I watched one of the machinists clip the collet insert into the threaded nut and wondered if mine was supposed to work the same way. Sure enough, I found the collet clips into the nut, and it takes way less effort to tighten the collet now. in my ignorance and impatience to get started making something, the first time I cut something, I put the collet into the spindle, spun the nut on a little, then inserted the bit and tightened it down, and had been doing it that way ever since. I imagine it's written down somewhere that the collet and nut are to be attached, then put on the spindle, but who has time to read?

[bauldy]

I would be confident that the collet is a standard Imperial size, the same one that comes with all machines shipped.
The Axiom bit set supplied in Australia however, is not the Amana one that is supplied in the U.S. (Due to cost)
I was assured that it is a good quality set, but perhaps check the actual size.
Alternatively, perhaps purchase an additional EM (you are bound to need another eventually!)
That way you can see if the issue is with the EM or the collet.

Regards

Bauldy

[redwood]

Just as Traindriver, I had used my ARpro6 a long time (over a year) and had no issues. All of a sudden my bit slipped. I assumed I had forgotten to tighten it, but when it happened again, right after, I ordered a new collet. Everything seemed fine again. Later, the slippage started again. I contacted Axiom and Chad asked whether I was snapping the collet into the nut. Whoa, I was a 40 yr. carpentry contractor that had a used a router quite a bit. I had never, as far as I can remember, snapped them together. Well guess what, they do snap together and I haven't had a slip since. I really felt stupid when I learned that.

[aussie]

Apr 4, 2019 13:23:07 GMT -5 redwood said:

Just as Traindriver, I had used my ARpro6 a long time (over a year) and had no issues. All of a sudden my bit slipped. I assumed I had forgotten to tighten it, but when it happened again, right after, I ordered a new collet. Everything seemed fine again. Later, the slippage started again. I contacted Axiom and Chad asked whether I was snapping the collet into the nut. Whoa, I was a 40 yr. carpentry contractor that had a used a router quite a bit. I had never, as far as I can remember, snapped them together. Well guess what, they do snap together and I haven't had a slip since. I really felt stupid when I learned that.

[aussie]

Yes I discovered that I had not been snapping the collet into the nut..... I think that was the problem all along.
Thanks to everyone for your suggestions.