Router Table Excitement

[Chet]

I was doing a little prototyping for an up coming project.  Yesterday I was cutting a grove using my router table.  because its a prototype, I was using some poplar and the grove was 3/8 wide and was going to be 5/16 deep.  I was on my third pass, the first being 1/16 deep, the second 1/8' deep and the third was the same.

About a two thirds of the way along I started to feel a growing vibration so I hit the stop paddle with my knee and held to work piece with the push pad standing back as far as I could with out letting go of the work for fear it would shoot off some where.  About then the router bit broke through the work piece which lead me to think the bit had come loose out of the collet.  But as it turns out the top 1 1/4" of the bit just broke off.  It chewed up my insert plate pretty good as well.

[wtnhighlander]

Dang! That's the kind of thing that is really hard to plan for!  Any idea why the bit broke?

[Dave's Not Here]

Somebody owes you a new router bit and possibly a new pair of tighty-whities.

[Chet]

On 7/5/2022 at 3:58 PM, wtnhighlander said:

Any idea why the bit broke?

Nope,  where it broke was under the table so its not like it hit a foreign object imbedded in the wood and I wasn't putting it under any undue work load, it was just a piece of poplar.

The bit was about five years old.

On 7/5/2022 at 3:59 PM, Dave's Not Here said:

possibly a new pair of tighty-whities.

They were fine.  there was some warning when the vibration started.

[Ronn W]

I have had collets come loose before but not what you experienced.  Glad you are OK.

[Coop]

Dang bud, glad Itwas only the router plate and poplar and not a piece that contained flesh and blood. Was it a name brand bit?

[Chet]

On 7/5/2022 at 8:24 PM, Coop said:

Was it a name brand bit?

Whiteside

[Tom King]

I'd replace the collet.   I think something happened to the collet.

Call and talk to someone at Whiteside.  I would expect they've seen it happen before.  I've talked to a guy there named Todd several times.  He has a good understanding of everything they deal with.

This doesn't diminish Whiteside from the top of my list of preferences for router bits.

[JackmanRobyn58]

Thanks for advice. @Chet glad you're okay.

On 7/6/2022 at 2:41 PM, Tom King said:

I'd replace the collet.   I think something happened to the collet.

Call and talk to someone at Whiteside.  I would expect they've seen it happen before.  I've talked to a guy there named Todd several times.  He has a good understanding of everything they deal with.

This doesn't diminish Whiteside from the top of my list of preferences for router bits.

 

[Chestnut]

Is it possible the bit got dull? 5 years isn't that long but with some good use it could have worn out. Looks like an all carbide bit?

I've broken a few core box bits but it's mostly because they went dull. The cutting action starts to vibrate and then the shaft breaks, not like this though.

Glad that your hands are safe and that there were no injuries.

[Tom King]

Probably worth a check of the router bearings too.

[pkinneb]

I agree with @Tom King my first call would be to Whiteside.

[Immortan D]

I'd check the router lift. Maybe it became loose causing the bit to drill into the wood.

[drzaius]

A very similar  thing happened to me with a brand new $135 spiral carbide bit. It loosened in the chuck just enough to work its way out and then all hell broke loose. The bit didn't break, but it was ruined. I always try to remind myself and others that those collets need to be TIGHT. It's not like a saw blade that will tend to tighten itself.

[Chet]

On 7/6/2022 at 6:39 AM, drzaius said:

I always try to remind myself and others that those collets need to be TIGHT

This is the thing I keep coming back to.  The shank was still in the collet and I had to use the tools to loosen it.  But it could be that I didn't get it tight enough and when the vibration started the shank got wonkie in the collet and made it feel like it was tight.

 

On 7/6/2022 at 4:41 AM, Tom King said:

This doesn't diminish Whiteside from the top of my list of preferences for router bits.

I am with you on this, the replacement that I ordered is Whiteside.

[Ronn W]

May not be relevent to your mishap but for the benefit of those with less router experience - it is important to raise you router bit about 1/8" up from being bottomed out in the collet before tightening the collet.  If you try to tighten the collet with the bit all the way seated in the router, you cannot get the collet fully tightened.  Then tightening action of the collet pushes the bit down ever so slightly.  You have to leave a little space under the bottom of the bit for this to happen.  I have had a couple of times when my bit came up through the wood before I learned about that.

[Tom King]

Collets do get to the point that they won't hold a bit, too.  I never figured out why, but have had it happen multiple times.  It may seem like it's holding, from the way it feels after tightening one, but the bit will still walk, even though it's grabbing hard enough to do some cutting.

[drzaius]

I suspect that slippage may be involved in collet wear. Another reason to crank 'er up tight.

[Tom King]

They can get to the point that regardless of how tight you turn the nuts, the collet still won't hold.   We took off 3/4" of about 200 square feet of the top of old flooring in an 1828 house, and wore out three collets in the process.  I even tried tightening them with two regular 1-1/8" wrenches, which are over a foot long each.  I never figured out what happens to them, or spent much time thinking about it.

[Mark J]

Any way to tell a collet is worn out?

[Tom King]

The only way I could tell was that the bit slipped longer.   I could tell because it became harder to cut, and made a different sound.  I wish I knew a better way.  The bits I was using were just straight cutters.  I expect things good get more interesting with a spiral upfeed.

[drzaius]

2 hours ago, Tom King said:

 I expect things good get more interesting with a spiral upfeed.

Oh yea.

[wtnhighlander]

I'm guessing that as the collet wears, the slots squeeze together and contact each other before the ID clamps down on the bit. At that point, it can never tighten enough.