Hot Collet on Porter Cable 7518

[DonkeyHody]

I got a Porter Cable 7518 3 HP router a few months ago and mounted it in my table. Awesome power and easy adjustment; I've been very pleased. Today, after running it for about 30 minutes with a 3/8 round over bit on some cypress, the collet nut was too hot to hold. The bit was a brand new Whiteside, and it never loaded the motor, so I suspect the heat came up from the router bearing instead of down from the bit. I've never had a collet nut burn me before. Anybody else experience this? Should I be talking to Porter Cable about a replacement?

DonkeyHody "Every man is my superior in that I can learn from him." - Thomas Carlyle

[Eric Ryder]

Examine the bit to see if the bearing had seized or if the shank was slipping in the collet.

[Edwin Pawlowski]

That makes no sense to me. If the motor was never loaded the bearings are probably just fine. 30 minutes of cutting wood will generate a lot of friction and friction generates heat and the heat will travel the path of least resistance. That would be down the shaft and into the collet nut that makes a good heatsink.

Did you grab the housing? Was it warmer near the top or was the collet nut hotter than the motor housing? How hot was the bit? Ed

[P©WÉ®T©©LMAN]

Suspect either an overheating collet end bearing on the armature or a dull bit heating up from excessive friction or simply too long an operating time without a break.

[DonkeyHody]

The aluminium router base was warm to the touch, but aluminium is a very good conductor and will draw heat from the collet anyway. The bit was warm of course, but cooler than the collet nut. The nut wasn't sizzling, but was too hot to hold onto. The bit was brand new, and the pilot bearing on the bit has not siezed. From the very light feed pressure required and the quality of the cut, I know the bit is plenty sharp. I suspect the shaft bearing next to the collet is failing, but I wanted to see if this kind of heat build up is normal before I get too excited.

DonkeyHody " We should be careful to get out of an experience only the wisdom that is in it - and stop there; lest we be like the cat that sits down on a hot stove-lid. She will never sit down on a hot stove-lid again---and that is well; but also she will never sit down on a cold one anymore." - Mark Twain

[Tony Mo]

the collet nut was too hot to hold.

I'm just thinking out loud here but when you put in the router bit and it bottomed out in the collet, did you back it out about 1/8"? I was told to do this at a woodshow demonstration so that the heat from the bit did not transfer to the motor. Maybe this is causing the same problem for the collet. Just an idea

"Keep your stick on the ice." Tony

[P©WÉ®T©©LMAN]

"DonkeyHody" wrote in message news: [e-mail]...

It's not normal to get that hot, the bearing is probably poor.....quite a common problem these days even with PC & it only gets worse if you continue to use your router without maintenance at this point, you could try a bearing lubricant spray if you want to find out for sure, remove your collet & turn the router upside down, proper bearing lubricant can penetrate most bearing seals & reactivate any original lubricant, spray lightly around the shaft past the treads & let gravity do its thing while rotating the shaft by hand, you may feel any resistance reduce as you do this, do not use too much lubricant as it may go past the bearing housing & on to the armature body. If you notice that the router runs cooler & quieter at the shaft area after this then this is your short term fix....when you get a chance replace the bearing ASAP unless the problem does not re-occur at all. After purchasing a can of bearing lubricant (which can last for years) you can always give a light spray before or after a period of extended use.(allow any excess to evaporate prior to turning on if you have applied to heavily (it is highly combustible). As an extra precaution make sure your router bit has not been allowed to bottom in the collet as this will allow the heat to easily transfer up the shaft to the bearing, even 1/16-1/8" is enough to cut down on the heat transfer considerably plus your collet will hold the bit more effectively with out having to overtighten due to binding, almost every router we have in for service has the router bit rammed up to far & the nut way overtightened.

[Swingman]

From experience, the 7518 has a tendency to get plenty hot with prolonged use, more so than any other router I've used and/or owned. However,the beast is basically all motor and you would expect a proportionate increase in heat during use. Thus far, the phenomenon has never been a problem in the three years or so I've used a 7518.

IMO, this tendency to run hot, and the resulting different rates of expansion of the metal parts, collet, bit, etc., may be one of the reasons folks seem to report more incidences of slipping bits with the 7518.

It is also my experience that proper installation of the bit is critical with this beast, particularly with prolonged use of a 1/4" collet and bit ... you'll want to check the tightness and depth of the bit frequently, or risk the consequences of a bit "climbing" in the collet.

[DonkeyHody]

Thanks to all for your help. The bit was 1/2 shank and I am religious about always lifting the bit to be sure it isn't bottomed either in the bottom of the collet or against the chamfer under the blade. I'll fire off an e-mail to Porter Cable and see if they'll replace the bearing or the router. Wish me luck.

DonkeyHody "Every man is my superior in that I can learn from him." - Thomas Carlyle