Router bits working their way out of collett

[Neville Bastian]

Every 4 to 6 months we seem to have a router bit work its way out of the collett even though its been tightly tensioned. Its normally the 9.6mm one we use in panel release. Is this normal? I normally replace it with a new collett. Can the faulty ones be repaired?
Is their a feature in control nesting that would know the spindle is working harder and under additional strain because it is cutting deeper than normal.If we are cutting 16 or 18mm at the same speed that should affect power draw or something. If that could be registered and a percentage window added it could send a message to the controller that it exceeds given limits. My thoughts are not go into emergency stop but reduce speed to 10% so the operator can stop things. Things can go pear shaped when emergency stop is pressed for no good reason. We did have a guy who pushed that to have a tea break. Hello, anyone home.

Regards

Neville

[Marius Gouws]

Morning Neville
It happen to me as well with my 8mm dado (compression) cutter when it cut 18mm deep or more. Here it happen quickly in a matter of like 300mm, it start pulling it out off the collet and snap it off. I set my max penetration for that cutter now to 10mm. When inspecting the cut that it makes when this happen you can clearly see that it just start to cut deeper at some point until it breaks.

[Neville Bastian]

Good afternoon Marius,
It does happens fairly quickly so I guess it would be hard to prevent visually. To stop it I think it would have to be electrically monitored which maybe more difficult than I think. Yesterday it went for about 2m before it severed. When this happens it also stuffs up the Z axis by not drilling at 90 degrees which is a pain to get right again.
So how are things over your way? The same as the US or getting better?

Regards

Neville

[Matt Snowball]

Same thing happened to me once. Bit worked its way out of collet about .75" before I noticed.

I check tightness on all collets every few hours cutting now. Haven't found one loosen off since though.

[Will Williamson]

But do you inspect and clean your bits and collets every time you install the bit? and do you clean and lubricate the end of your collet where the nut contacts the collet every time?

[Neville Bastian]

Hi Will,
We don't lubricate or clean except for a spray of Dry Lube. We were told not to scratch the surface as our previous machine we used to clean with steel wool or fine sandpaper 400g.
Maybe if the Thermwood staff reply on what is the correct method or refer me to the service manual.
Thanks

Neville

[DanFecteau]

It happens to me this week but it's always when there's a lot of stress on the tool. I was cutting 1 3/4" solid maple, first pass at 1" depth and the tool was only 1/2" diameter and 4" long so it was probably vibrating cause it was not deep enough in the collet....I think that's the main reason of this problem.