Router Overheating

Woodworkers discuss how hot router bits and collets should be expected to get during normal operation, and what might cause them to overheat. September 7, 2006

I have two PC 7518 routers - one mounted in a Precision Router Lift in a router table and the other one in a Legacy Ornamental Mill. They both have Eliminator chucks. My problem is heat. The arbors and chucks on both units get very hot. They can be held in my hand for just a short time before it starts getting uncomfortable. It does not matter what bit is being used and I never use them for heavy cuts. The same problem existed with the original chucks. And the routers are being run less than 30 minutes. My question is this normal for the Porter Cables or do I have a problem of some kind? I have an old Makita 2 HP and a Bosch 3 1/4 HP and don't experience any heat problem with them.

Forum Responses
(Cabinetmaking Forum)
From contributor A:
I have the 3.5 hp PC router and it gets hot. The original bearings were fine but when those wore out, the new bearings seem to get the collet hot. Not the bit, but the collet. But it has been running for almost a year and still runs fine so I guess it's OK.

From contributor B:
If you can hold it in your hand for a short time before it is too hot to hold then it is not hot, it is very warm - probably around 115-120º F. This is not hot for a steel or carbide bit, or the collet and bearings. When things get above 250º F then you should start to think you have some sort of problem. Cutting wood generates heat, and the heat is transferred from the bit to the collet and bearing, and it goes the other way around too. The motor produces heat and transfers this through the shaft to the bearing to the collet and bits. If you have ever burned a piece of wood using a router then the surface temperature of the wood/bit meeting area has exceeded 400º F - an average temperature where wood will scorch or burn. I don't think you have anything to worry about.

From contributor A:
In my router the bits are not much warmer than room temp. I can touch them without any discomfort. However the collet and lower portion of the router is very hot – too hot to hold. I would assume the bit would not transfer cutting heat (friction) to the collet and stay cool. However, the heat transfer of carbide (or the rate of cooling) may be such that this is in fact what happens.

From contributor C:
It doesn't sound right to me. I have several PC 1-1/2 hp routers and a 3hp Ryobi and the collets don't get hot. Maybe the gizmo you put on it is slipping. Try a standard setup and see if it heats up.

From contributor B:
You can do a simple test. Turn the router on and just let it run. No load, no cutting. Let it run for 15-20 minutes. Check the temperature of the collet area now. Is it very hot? If so, it may have a problem. If not, it is probably just the inductance heating of the coils being transferred through the metal parts. The router bits would stay a bit cooler because they have the best opportunity to have a cooling breeze. If it doesn't seem to affect the operation of the routers, so don't worry too much. If you can smell electrical burning, then you should worry. Shut things down and keep an eye one it in case it catches fire (highly unlikely).

From contributor D:
I have noticed my PC routers collets getting very hot also. Of course, with the temperature in my shop at almost 100 for a week everything is running hot.

From contributor B:
At the Shop Bot forum they came to the conclusion that the bearings supplied with the router and through the service centers were faulty. They gave some specific bearing replacement numbers. I suggest you talk with you PC rep. Have them replace the bearings, under warranty, with the correct bearings. These are the bearing numbers:
6202ZZE/C3 and 6005ZZE/C3.

From the original questioner:
Thanks to all for the comments and suggestions. To me, the bottom line seems to be that Porter Cable has a design/manufacturing problem. Why should we pay high dollar for a new router and then have to replace the bearings to obtain performance that should be expected out of the box?

Like I said in my original post, a 20 year old Makita that has been used like a shaper and an eight year old Bosch have never had this problem. Neither unit has ever had the bearings replaced and only replaced the brushes in the Makita a couple of years ago.
Again, thanks to every one.

From contributor F:
I own a bunch of PC tools and the truth be known the answer is simple: Makita and Bosch just plain make superior machines. The really scary part is that PC, and Delta are now Black and Decker owned. I guess we can guess where this is heading.

From the original questioner:
Until the acquisition of three pieces of equipment in the past couple of years that use the PCs, I never owned a PC router. Perhaps by the time these fail, another company will have a round body the same size. I've had very good luck with the Makita and Bosch but thought the PC would be good also.

From contributor F:
At the way tools are going there will probably be only one company making all our tools and who knows what name it will have. Just another point if you don’t already know this, Milwaukee tools which were so great and well known are now owned by Ryobi. If you call Porter Cable directly and explain your problems they will just about turn the world upside down to help you, really. I have had several reasons to them in past couple months and they were outstanding in their help to the point of sending free parts that the service centers claimed were no longer available, which was the reason I called them. I didn’t get the chance to holler - they just upped and solved it. If you go to PC website under "contact us" you will find their 1-800 number.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor G:
I had the same issue of overheating and bought an Arizona vortex mini cooler. I connect it to the router (it is small) and it blows cold air onto the bit as well as blowing about the dust.