Cool Bit, Hot Collet

[rcnewcomb]

We just swapped out the Porter Cable router with a replacement. I've noticed after running a job that the collet is quite warm but the bit is only slightly above room temperature. The collet is the one that came with the new router. I haven't tried a different collet yet.

Anyone recall what makes a collet hot but the bit cool?

[ken_rychlik]

Probably the bearings are not broken in yet. If it doesn't get better, the bearings may not be any good. Just becasue they are new doesn't mean they are good.

Kenneth

[myxpykalix]

I have experienced the very same thing on several occassions however I don't believe it is a bearing issue. The reason i think that is because I could cut something the very next job and for a longer or shorter time and it not have any heat. I have tried to take mental note of what i was cutting, length of time cutting, material, ect to try to discern a pattern to figure it out but have yet to know what it is.

Randall are you using .5 or .25 bits when this occurs? What material are you cutting? Are you doing 2d or 3d cuts?
It is the craziest thing because you can grab the bit and hold it but the collect will leave a red mark it is so hot.

My theory is that it is a transfer of heat from the material to the bit, to the collet. I have taken the collet off and felt the threads where the collet screws in and that is not hot like the collet.

It is funny because i have felt the collet after a 6 hour 3d carving and its cool and then done a 5 minute 2d cut and it burns your hand. I think its friction and the type of metal the bit is versus the collet.

[ken_rychlik]

Ineresting Jack.

I guess he could take the collet nut off all the way when it's hot and feel the shaft of the router to get a better idea.

Kenneth

[burchbot]

Hi Randall
I had that problem with my P.C. from day one and it is six years old. All I need to do is turn it on and let it run for a few minutes. I emailed P.C. years ago about the problem and they said it would stop when the seals broke in. It never did.
Dan

[paul_z]

I had the same problem with two PC routers. After dozens of hours of use, the collet temperature dropped. I assume it was the bearings.

Paul Z

[rcnewcomb]

So some of these 12 hour 3D toolpaths that I'm prototyping now may be just the right medicine, huh?