Porter Cable HEAT

[stickman]

Guys,

I bought a rebuild kit and had our local tool god replace the bearings. I was sure it was causing an overheating problem at the collet. I got it home tonight and the ran the router for less than a minute. The shaft of the router was too hot to touch. I took the top of the router and the top of the shaft is hot at both ends.

WHAT is the deal? Anyone had a problem with the Porter Cable like this? Can someone point me into a direction or is my router burned out? Would love some help on this one... I thought I'd be up and running, but yet I am a fish out of water. AGAIN! :o(

Is this covered in ShopBot's warranty?

Jay

[olecrafty]

Jay,
If the new bearings are installed properly you may have an electrical problem. Four causes that are usually associated with heat problems are;
1. A problem with the brushes can cause a heat build up.
2. The electronic components that control the speed are in trouble causing the wrong voltage to go to the windings resulting in heat build up in the rotor.
3. A short or open in the windings will produce heat in the rotor also.
4. A short in the rotor itself will cause heat build up also.
Good luck I hope this helps.

Kaiwa
olecrafty@charter.net (mailto:olecrafty@charter.net)

[dingwall]

Jay, the bearings are packed full of grease when new. Run the router on low speed for 30 seconds. Feel the collet. If it's warm,let it cool down and then run it for 1 minute. Let it cool down and run it for another minute. Keep doing this until it can run for a minute without significant heat. Then try for a couple of minutes.

I broke my new bearings in over the course of an afternoon and now it runs fine.

[stickman]

Sheldon and Kaiwa,

I spent the weekend in frustration. My router still is heating up. I might go out and let it run for awhile. I am taking it to work with me and dropping it off to the service tech. See if he can find anything else wrong with it.

I am going to guess that it is electrical. The router collet get screaming hot and then the whold body gets hot. It will still be hot a hour later.

I have a Porter Cable ordered and should be here mid-week. I am hoping that it will be covered with Porter Cable's warranty.

Thanks for your guys help.

Disappointed,

Jay

[Mike Windsor]

I'd be interested to know what the problem / solution is . ---I just noticed my pc router doing the same thing all of a sudden . I first noticed it while changing a bit and the collet was too hot to hold . I changed the bearings about four months ago and it didn't start running hot until recently .

[waynelocke]

I am also following this thread with interest and have the same problem. I changed the bearings and the collet gets too hot to handle. There is no bearing noise of any sort. I have follwed Sheldon's advice on breaking in the bearings but it does not seem to have helped. I would love to know what the tech says.
Wayne

[olecrafty]

I run 2 Z axis and do a lot of production runs. When the first PC failed I was in the middle of a run with a short time frame. I am near a PC repair shop so I hotfooted it over there for repair. After finding out there was a month backlog I bought a factory rebuild to replace it with while being repaired.

The factory rebuild lasted all of 15 minutes before the heat problems began. The router was so hot I had to let it cool to remove it from the machine. One of the brushes had failed and shorted to the housing. A quick trip to the repair center (this time the router was on the bench as soon as I walked in) a change of brushes and I was back in business. Now when one quits I send it to PC for repair install the spare and go back to work.

Most of my cutting is in hardwood and many of the cuts are full deep cuts with 1/2 inch endmills, If the router isnt crying for mercy I speed up the bot. I us a steady stream of compressed air to help remove chips and cool the endmill. A little rough on the equipment, but I have built my business on doing things others turn down becouse of short time frames and complex task.

I guess I wrote all that to say check the brushes. I know long winded Texas approach but at least I had a point.

Kaiwa
olecrafty@charter.net (mailto:olecrafty@charter.net)

[gerald_d]

Some things that can go wrong with small bearing changes in general (I have never seen a Porter Cable in my life):

1. The replacement bearing has the wrong type of shields or seals. High-speed bearings have non-contact "shields" as opposed to rubbing "seals". Seals are more expensive and therefore some sales people will tell you that they are better - not true for high speeds where the rubbing seals run hotter. (an example, from a spec sheet for a 15mm ID bearing, the max speeds are 24 000 rpm with shields, and only 15 000 rpm with seals. Most power tools (drills, angle grinders, skil saws, etc.) run at the lower speeds and it is good to fit "sealed" bearings to them - however, the repair shop is doing you no favours to give you a "sealed" bearing for your router)

2. The replacement bearing has the wrong "clearance" (runout?). Bearings are available with different internal clearance specs - you need to fit the same that the OEM factory used, because they know how tight the housing and shafts are. A replacement bearing salesman seldom cares about that. (Metric bearings have a C3 marking that shows extra clearance)

3. The bearing housing and shaft were not perfectly clean - the bearing is squashed into a smaller space than it is supposed to go.

4. The shields/seals were damaged during the installation - the punch tool made a small nick in a shield and there is now friction.

5. The bearing is sitting at a slight angle to the shaft. The method used to push the bearing onto the shaft was pushing at one point only.

6. Hammer forces were applied to the balls of the bearing. eg. while fitting the bearing to the shaft, hammer blows were applied to the outer ring. Bearings must be pushed gently into place, using a pipe that fits over the shaft, and which pushes on the inner ring only. Similar approach for pushing a bearing into a housing. Hammer and punch method only for the experts.

7. The bearing has not seated to its proper "home" position. ie. when you tighten up the motor housing, the bearing experiences an axial force. Very tricky to solve. See point 3.

[olecrafty]

one to add to the bearing list. Incorrectly place bearings can shift the position of the rotor. This can cause excessive vibration or heat or both.

Kaiwa
olecrafty@charter.net (mailto:olecrafty@charter.net)

[stickman]

My router is back at the service center. The tech is going to check it out, top to bottom and inside and out. I'll update ya'all when I know more. Or what they decide to do with the router.

[waynelocke]

Jay,
What did the tech people find?

[stickman]

Wayne,

The tech is replacing the field coil in the router. Sorry I hadn't gotten back to the group on this. I ended up buying another router for backup. Right away it got hot, so I'd run it for a little while. Runs cooler now, but its still getting warm.

Jay

[gary_n]

Wayne,

How long has your router been getting hot? It seems now that mine is also getting hot. I just had mine overhauled at Porter Cable service center in Dallas. Maybe I need to take it back.

[cnc_works]

I have a new PC 890 and several PC 690's and one 7518. All the smaller routers get hotter than I would like to touch after any prolonged cutting. New, factory rebuilt, shop rebuilt all behave much the same. And it doesn't seem to make any difference about the air circulation. My smaller router is completely enclosed and the SB is open.

Since it seems to be consistent across all the routers I use, I just run them. I'm not happy about them being so hot, but it doesn't seem to make any difference in bearing life or performance. I seem to get my 100 hours, give or take, from them no matter. The 7518 doesn't get as hot but I only run it in the open SB when I really need the extra power, which isn't often.

I know I haven't contributed much to the discussion, but maybe my experience will be interesting to someone.

Donn

[billp]

Donn,
Am I reading that right? You only get 100 hours per router? Are you consistantly running your machines at their top speeds and in thick materials? I've got a PC 3.25 on my machine for over 5 years now,used it daily, and only changed the bearings last year...

[cnc_works]

Bill, my failing seems to be that I am never specific enough.

The only router I have a long enough history with to make an observation about is the PC690. And, though keeping exact records is impossible for me, I seem to have to replace bearings every six months or so. Given that sometimes a week will go by without my turning on the CNC and other times I'll run it two or three hours a day, I'm just guessing at the 100 hours in six months.

Again, this is in an enclosed cabinet on a small CNC with 300in/oz steppers. I haven't had the SB with the 7518 and 890 long enough to make any judgements.

And, most of the cutting is moderately light. Engraving and lithophanes for instance, though I do cut a fair amount of Corian. When I do have to cut thick/hard material, I probably err on the side of too many passes, so the stress on the bearings should be minimal.

Donn

[gbatten]

Donn,

Have you checked the voltage to the router? Make sure you are getting full voltage "at the router". Low voltage can lead to higher operating temp due to increased current flow (I think). If you are using a long drop cord to power the router, that could be contributing to the problem. It is also possible that the power company is delivering lower voltage to you. This is just my opinion. Good luck.

...Gene

[kerrazy]

Check the size of wire running to your router as well. I would suggest no less than a 12 guage wire running any distance to the router. While the router is running hold the extension wire and see if it is hot as well. If so this could be the root of your problem and I would definatley run a heavier guage wire to the router.

[stevem]

This is not a problem with the wiring to the router.

I’m on my second model 7518 in 5 months for the same problem. Changing the bearings is not the cure. Just received the router that was new last Wednesday after sending it to Porter Cable for repair this past Monday. Porter Cable deems the overheating collet to be normal.

Although I believe this to be a design or manufacturing flaw in the router, I have to admit that customer service at Porter Cable is exceptional.

[kerrazy]

I have been running my router since my last post and just checked the collet for heat, and it is truly insignificant. Something funny going on for you guys.
I am in the middle of carving a two sided 4' X 6' Cedar sign with lots of hogging out and V-bit work.

Dale

[waynelocke]

Gary, I have been out of town for several days. My PC began getting hot when I changed the bearings a month or so ago. I bought the bearings at a bearing supply house and the larger bearing had a different shielding than the original ( I don't remember exactly but that was the only one they had) I just received some official PC bearings last week and am going to try them.
Wayne Locke

[stevem]

Has anyone managed to solve the overheating collet problem? The hot collet is imparting heat to the HSS bits and causing them to burn within 20 minutes of use when cutting plastic. The bits get too hot to touch even after 15 minutes of spinning in the air.

[bruce_clark (Unregistered Guest)]

Steve,

While this may not be a "fix", it could be used as a "work around".

They are "cold air" guns

http://www.process-controls.com/Pelmar/Spot_Cooling_Systems.html

They are most excellent for plastic and they--the manufacturer--recommends them for grinding as well. Something to consider.

Bruce

[billp]

Steve, At the Oklahoma Camp Joe Crumley had a unit called an "Arizona vortex CNC cooler". It was easily mounted on a'Bot by a magnet, and the claim was that it reduced the temperatuire of the air coming out of it's nozzle by something like 75-90 degrees. When they turned it on there was definately some very cold air being sprayed onto the bit. www.arizonavortex.com (http://www.arizonavortex.com)

[stevem]

Bruce and Bill, I am familiar with the vortex cooling systems, but there has to be a solution for the overheating router. The router design or assembly appear to be defective.

[Brady Watson]

I have a small 1.5HP PC hand router and it only has maybe 1 or 2 hrs on it tops. It also gets hot. I am wondering if this is just a PC thing or do other routers like the Bosch and Makita have the same symptoms?

-Brady

[stevem]

Brady, I have 3 Makita routers. Yesterday my homebuilt CNC router ran 6 hours non stop. The Makita collet was cold to the touch at the end. I suspect the PC router will self destruct the day after the warranty expires.

[stickman]

UPDATE... ...UPDATE

I picked up my PC router. The tech replaced the field coil and fixed a bearing problem. The top bearing's outer collar was moving within the housing.

Got it home tonight and ran it for about three minutes. The collect got hot. I held onto the motor casing while it ran, you could feel the heat building up. The service tech is confused and much that he gets from Porter Cable is not much.

Does anyone know of any barrel type router bodies like the Porter Cable that would fit into the Shopbot saddle.

So that's where I am at with that. Another note, from a source I've heard that a big name tool maker has bought Porter Cable.

Well that is my news for the night on the Porter Cable heating situation. I am hoping that one day I can upgrade to a spindle.

Jay

[windsor@muskoka.com]

I have two PC routers . The newer on that I changed the bearings in recently is getting smoking hot after about ten minutes of running , . I was doing a long part file where acuracy wasn't too critical , and decided to put the old router in the machine . with the old router after running for three hours straight the collet and router body are almost cool to the touch . --with the new router and bearings the collet is to hot to touch . I might try changing the bearings again , but am wondering if it might be some type of bearing pre-load problem ( between the top and bottom bearing ) that's making the heat ?

[waynelocke]

I think that Black & Decker bought Porter Cable which does not seem like a good thing.

There seems to be a definite problem with changing the bearings. Mine was cool to the touch until I changed the bearings. I still have not put in the official PC bearings. It would seem from these posts that PC techs have the same problem.

[gerald_d]

I have said of lot of this before...

Here (http://www.edswheels.com/faqbearings.html) is an easily understood story on small bearings - don't laugh at it because it is from a skateboard website! (They even explain "ceramic" bearings)

The main reason that I posted the link, is to show the difference between shields and seals. And at that website they also seem to have the attitude that seals are better than shields. Powertool repair shops think that they are doing you a favour by supplying sealed bearings as opposed to shielded bearings.

However, at very high speeds, the friction of seals does cause a higher heat build up and they do run hotter. Until they literally melt away at the rubbing surface and start behaving like shields.

If I pick a 20mm ID bearing from my catalog (42mm OD, 12mm wide), and look at the manufacturer's recommended max. speed, the following picture emerges:

Open bearing (no shields or seals) oil lubricated: 20 000 rpm
Open bearing with grease: 17 000 rpm
Pre-greased shielded bearing: 17 000 rpm
Pre-greased sealed bearing: only 11 000 rpm

Summary:
- 1/2" collet routers running at 20 000 rpm are running above the limits recommended by the bearing manufacturers.
- Make sure that you have shielded bearings (often slightly cheaper), as opposed to sealed bearings that most people think are better.
- New bearings often run hot for a while, and eventually settle down to a lower temperature.

Then one must also watch the bearing clearance (http://www.crsrl.com/Technote/engnote2.htm)<-link. You can walk into a bearing shop with a sample bearing in your hand, and the salesperson will give you a "normal clearance" CN bearing, unless you specifically ask for an extra clearance C3 or C4 bearing (America may have different codes for the clearance). It is standard practice for a tool repair shop to buy bearings direct from bearing suppliers, and they buy the standard clearance sealed bearings as a rule - but your router may be a lot happier with with a shielded extra clearance bearing, as may have been fitted at the router factory originally. Our Metabo certainly wants a 6201.2ZR.C3 bearing as opposed to the typical 6201.2RSR bearing. (Standard Metric designations used by many suppliers)

[paco]

I have this feeling about the PC collet... Mine too is getting hot with only few seconds on... but right at collet... Anybody tryed another brand/type of collet on his 7518 PC?!!

[gerald_d]

A tight collet cannot generate any heat. However, a permanently slipping collet would get so hot that it would weld itself to tgether!

(PS. I am away on business - enjoy the relative silence from me for a few days more!

[sheldon@dingwallguitars.com]

Has anyone checked into ceramic bearings for the PC?

[sagreen83]

Paco,

I am running the Eliminator RC chuck on my new PC and I am not seeing any heat problems at all. But I didnt try it with the original chuck, so I dont know if it generates heat or not.

Scott...

[paco]

Hey Scott!
Mine too is new... Willing to try the original collet? I plan to try running my PC for few minutes without any collet to see... By the way, bit is'nt hot... only collet!

Gerald,
do you have a clue of what is happenning wih our PC? Where talking of a general user trouble with new and used PC router...

Thanks in advance!

[paco]

Chuck too hot to touch after 1 min. without any collet!?!? In my area, services center have'nt seen or heared about any trouble of this kind on PC 7518!?!? Maybe we (users who own "hot" PC 7518) could compare our serial number... Mine is 123863 A 3031... Curiousity...

[stevem]

Paco, I note that you are in Canada.
The overheating PC spindles are a common problem, but most people who don't use multiple bits on the same job have not noticed it, since they are not touching the collet after cutting. I have been in contact with the service manager at PC Canada, so he has now heard about this problem. He doesn't know how to fix it, but seems to be trying to find a cure.

[paco]

What is he considering? In what kind of delay? Would you share contact so I can "PUSH" too?!!!

Hey Steve! About your probe??? Any update???

[stickman]

I haven't had a chance to run my rebuilt porter cable, but I wanted to also let you guys and gals know a few things on the PC.

My service tech noted that the top bearing was moving in the casing. That motion was creating head that was traveling down the shaft of the router. He scored the sides of the bearing housing in order for it to "stick" within the housing. Gerald also noted that bearings tend to heat durning inital uses. So when I get a chance I will change out routers and let you know.

Jay

[kerrazy]

Scott,
Get rid of that RC collet, before you get injured.

I ahve run one here and the 1/4 inch insert slips severly and will cause some real problems for you.
Dale

[jay]

Well,guys I too now have a problem with a very hot new rebuilt Porter Cable. It was rebuilt at the PC repair depot four or five months ago. I just installed it the other day and was very disappointed to find it was running so hot I could hardly change the bit in it. I called the repair depot and talked to the manager. Asked if he has seen a difference in the bearing over the last year or so. He said he has. His comment was the bearing they have now look as though they came from China when compared to the bearing they used to use a year ago. I sent the router back under warranty and ask to have premium bearings installed. He said it may cost a little extra but to me it is worth it. My other PC, I rebuilt a month or so ago with no heat problem. So, in future I'll do my own rebuilds. I can still purchase the brushes from PC for $14 and change, they are easy to replace. I will look up my invoice for the manufacturer and part number from the local bearing supply shop and will post the manufacturer and number in a day or two.

[jay]

Sorry for the long delay in getting back to the forum but . . . stuff happens.

After sending the router back to PC under warranty it was returned with another set of new bearings. It now runs as cool as it did when new. Maybe they had a bad shipment of bearings or changed suppliers and after all our complaints they have gone to a different supplier or different bearing.

I am happy now. Well, a little ticked it still cost me an extra $20 for shipping the router back to them to fix their crummy bearing. Tried to get the $20 in parts or refund but they would not bite.

[Jim Avey (Unregistered Guest)]

PC 7518 router. Whats the trick to getting it apart? I have replacement bearings ready to install. I removed the screws at each end thinking the motor would just pull apart. That didn't happen. Does the collet unscrew from the arbor somehow?

[ron brown]

Jim,

The Collet will remove with an impact and 1-1/8" socket.

Ron

[Jim Avey (Unregistered Guest)]

Well that worked nicely! Now, where can I get replacement brushes online?

[ron brown]

Jim,

I got the last two sets I bought from Porter-Cable repair centers.

http://www.acetoolrepair.com/PorterCableHTML/75182.htm had parts lists available when I posted this. ShopBot carries some Porter-Cable parts.

Ron

[jumbaugh]

Has anyone tried the Milwaukee 5625 router? Supposed to be 3.5 HP with 36 variable speeds sealed bearings and 5 yr warentee as opposed to porter cable. Also, if anyone has done it, the Milwaukee has a body diam. of 4.01 and it appears that the porter cable is about 4.25, which will help on room for dual z units. We are using the cast (alumninium) holders for the routers, and would this down size work or need modifications such as going back to the original stainless steel clamps?? Thanks

[billp]

Jim,
I think that's the same model I tried, and reported on here; http://www.talkshopbot.com/forum/messages/29/5842.html#POST20544
If so, it IS about.15 thinner than The PC and I had to shim it to get it to hold firmly in the existing mount.

[paco]

Hi Jim!

It's been about a few weeks now that I installed the 5625. This motor is fairly easy to installed but not "plug & play" as the PC 7518; you'll have to remove the "Height adjustment Shaft assembly" and free the "Cord protector" to avoid having the cord getting squeezed at the Z bay.

As for the motor size difference, it's about 0.040" smaller than the PC 7518; shiming is enought.

Here's a pic of what it look like once installed...


3900

Come back if you need more infos... I'll post the mail I've already fowarded a couples of time to others...

[paco]

Hey Bill!

Thanks to you for sharing with me (us) your obervations about the 5625 (I belive you were the first); that's what convice me to try it... and I VERY happy since!

[kerrazy]

Hey guys,
The Router heat problem was covered ealier, it is the bearings that are causing it to overheat. THe new bearings PC is using from the factory as well as the rebuild ones are terrible. Any repair guy worth his salt should have caught that. I had my Router taken in over XMas shutdown for an overhaul, and told him to ensure he did not use the currently supplied rebuild ones from PC as they are cheap off shore bearings.
Sure enough he did use them, but atleast he was smart enough to run the router to realize what I was talking about. He put the good bearings in and no problemo, no heat, no vibration.
Gerald you put me onto this in the beginning with one of your earlier posts, last summer maybe? Could you shed some light as to the appropriate bearing type
Dale

[stickman]

Dale,

You've been a silent one on the forum, has that shopbot of your got you tied to the shop or have you purchase three more Alphas?

Do you have a supplier or the specs needed for GOOD router bearings. I am coming up on my second rebuild, here shortly and would really like to get away from the factory bearings. I know if I purchase the bearings, my "great" repair guy, will not have a problem putting them in.

Thanks

[Andy (Unregistered Guest)]

This probably isnt going to help anyone but I run a 5.6KW spindle and this also gets RED hot. Not only the outer casing but also the collet and cutting tool. I'm not sure of this has any bearing on your porter cable system problems but I thought I'd let you all know that spindles get hot too- just in case this helps.

As far as I know the elte spindle I have is factory sealed and there is no servicing that I can carry out on it. It's a three phase system. I have been in touch with ELTE direct in Italy and they don't seem too concerned (although my Italian stinks and their English isn't too hot). I haven't had problems with collets sticking or jamming although it's a bit of a concern as I've burnt my fingers a few times

I shouldn't really be posting on here as I don't have a shopbot- I've just found that this site is the most helpful CNC site anywhere on the web.

In so far as cutting plastics goes I found that Perspex (plex) needs to be cut quite slow or everything gets hot, sticky and real messy. I broke a whole heap of Onsrud cutters trying to wizz through 5mm plastic- whoops.

[jumbaugh]

Thanks Bill and Paco, Based on your experience I'm going to go ahead with the Milwaukee. I currently have three porter cable routers and one is ALWAYS in for repair. Paco, I will probably be getting back to you when I get it for the fine detail of installation. Thanks.... Jim

[richards]

Replacing the bearings in the Porter-Cable 7518 is a fairly simple procedure requiring few tools and taking about 45 minutes for left-handers (right-handers could probably do it in half that time).

Yesterday I bought the SHIELDED bearings (6202ZZE/C3 for the top and 6005ZZE/C3 for the bottom. This morning, I dismantled the old 7518 that's been chugging away in the router table for several years. Since I had never replaced bearings in the 7518 before, I called all of the authorized repair centers in the Salt Lake area and found out that everybody is either on vacation or too swamped to get it back in less than a week. So, off to the local auto supply store to buy an air impact wrench and a 1-1/8 socket to remove the bottom bearing.

The only tools required were the impact wrench and socket ($35.00 total), a phillips screwdriver, a T20 Torx screw driver, a channel-lock pliers, a leather belt to protect the rotor from the pliers while the impact tool was removing the nut, a 5/8-inch socket, a 13/16-inch socket (both used as bearing pusher/seaters), a 5/32 allen wrench, some denatured alcohol to clean things up, a hammer to gently tap old bearings out and new bearings in, a few scraps of MDF to protect things from the hammer, and the air compressor to power the impact wrench and to supply air to blow out dust. I also shortened the power cord to about 18-inches to make it easier to manage. That required the usual cutters, strippers, heat-shrink tubing, hot air gun to shrink the tubing, 1/4-inch quick-disconnects, and a crimper

After finishing the first 7518, testing it, and then running it for twenty minutes, I was so impressed by the LACK of heat, that I replaced the bearings in the 7518 on the Shopbot. Both routers sound better and run much cooler.

If I can do it, anybody can.

[gerald_d]

6202ZZE/C3 & 6005ZZE/C3

The red ZZ's confirm they are shielded bearings and the green C3's show that they have extra clearance for higher temperature (or tighter housings). Totally the right choice for very high speed in an area that is prone to overheating. Personally, I would also fuss over the brand name and country of manufacture - we use SKF from Europe.

[marshawk]

Gerald,
Where do you get these bearings? I have tried a search on the SKF website, but it comes up blank.

Thanks,

Chip

[gerald_d]

Link1 (http://www.skf.com/portal/skf/home/products?newlink=1_1_4a&lang=en)
Link2 (http://www.skf.com/portal/skf/home/products?newlink=1_1_16&lang=en)
Look at the "Product tables" in the left column - Single Row Deep Groove bearings.

Or, just phone your bearing shop and see if they understand ZZ (or 2Z) and C3 - I am sure that they will.

[gerald_d]

Your nearest (6 miles west of you) authorised SKF distributor:

Ardom Bearing Group
1000 Bennett Boulevard
Lakewood NJ 08701

Phone: 732-370-2310
Fax: 732-364-5013

Tell them you want single row deep groove ball bearings with two shields (ZZ) and C3 extra clearance, then tell them inner diameter, outer diameter and width of each bearing. More than this I cannot do!


And something that I should have said first....

A big welcome to Chip Marshall, who must be related to Gene!

[marshawk]

Thanks Gerald, I appreciate the info!

Yes...Gene is my brother, although I try not to spread that around ;-)

I have been lurking on this forum for a while, but will try to be more "type-ative" in the future.

Thanks again,
Chip