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View Full Version : PC Router suddenly got quiet



mjindustry
12-15-2008, 08:12 PM
Hello guys. I was running a practice file on some pink foam today and all of the sudden the PC 75182 router got really quiet. Well like half as loud as normal anyway. Then it ran that way for the next five minutes and the part was done. Is this an indication of something, like does it need to be replaced now? I bought this used and I know it had plenty of hard hours on it. Thanks for any ideas...

Jason

GlenP
12-15-2008, 08:36 PM
Hey Jason, wish mine was quieter, perhaps this is the calm before the storm! Keep a spare router just in case. Good luck and have fun.

steve4460
12-15-2008, 09:51 PM
Check the brushes . They don't cost that much and are somewhat easy to replace .

blackhawk
12-16-2008, 11:39 AM
Jason - I am an engineer for an electric motor company. With a brush type motor, the motor will run quieter after the brushes are worn down to match the commutation surface. We usually run our brush motors for 6 to 24 hours straight to break in the brushes. The noise will drop dramatically during this time. But you say that the motor had a lot of hours on it already. Sometimes we have found that the brushes have hard deposits embedded. This can cause noise, so you may have finally burnt through the hard spot and into the good part of the brush. We had a suspect brush supplier once, and we had their brushes analyzed by a lab. The lab told us that it looked like they swept the floor and threw that into the brushes that they were making. Hopefully these same people don't supply Porter Cable.

If your router is running cool, not drawing too many amps, the RPMs are correct, and the runout is good, you should be OK. Just keep a check on it.

mjindustry
12-16-2008, 02:23 PM
Thanks guys!

Well I went to run a new file today and the router wouldn't even turn on. It seems to be dead now.

What does a guy do with one of these when it doesn't even turn on....Is it time to buy a new one?

blackhawk
12-16-2008, 02:40 PM
You can replace the brushes and also replace the bearings. There are several old threads about doing this. Shopbot sells the brushes and I think the bearings also. Someone on one of the threads bought their bearings from MSC.

Here is a link to a post that I just did for a brand new PC router, available on Amazon. This is the best price that I have seen.

http://www.talkshopbot.com/forum/messages/15719/36786.html?1229382199

ljdm
12-16-2008, 02:54 PM
Might want to check with Shopbot - when I bought my brushes and bearings from them earlier this year, they said they weren't going to sell them anymore.

steve4460
12-16-2008, 09:06 PM
Call porter cable for parts or repair stores in your area . I just had to do mine and they are cheep . the shipping cost more then the brushes.

mjindustry
12-16-2008, 10:35 PM
Seriously!!??

The thing doesn't even turn on...I just need to replace the brushes and all will be fine?

steve4460
12-16-2008, 11:15 PM
Thats what mine did not to long ago .when you open up the top make sure you don't lose the slider for the variable speed and then with compressed air also blow out the switch . fine dust has a way of getting in there .Keep us posted on how the surgery is going .

mjindustry
12-17-2008, 12:17 AM
Thanks! Brushes ordered.

bcammack
12-17-2008, 09:02 AM
We used to break in our slot car motors by running them immersed in a cup of distilled water. (seriously!) Shortened the break-in time to about 10 minutes..

robtown
12-17-2008, 10:52 AM
I've had two PC routers that the switch has gone bad on.

mjindustry
12-17-2008, 11:37 AM
Seems likely that brushes are the issue here most likely? Remember, the router got quiet and ran really slow and then next time wouldn't start.

Regardless of the outcome here, I'm going to be purchasing a new second router and maintaining a backup.

rb99
12-17-2008, 12:11 PM
I used to send them out and get the bearings replaced (with an upgraded bearing) as well as the brushes etc.

RB

jeffreymcgrew
12-18-2008, 07:43 PM
When it got quieter, did it also start spinning a lot slower? We've gotten too much dust in our speed controller to where it wasn't getting a good connection anymore and had some strange issues with the router not holding a consistent speed. Took it apart and cleaned it all up and the problem went away.

But new brushes aren't a bad idea anyways.

mjindustry
12-18-2008, 11:23 PM
Jeffrey- It did spin slower when it went quiet. I took the brushes out today but my new ones aren't here yet. It looks really dusty inside the router and around the speed switch. I will do my best to clean it out before reassembly.

Brush Condition Update: The brushes look to be worn down to about only 25-30% of original length when compared photos of the new brushes on the web.

mjindustry
12-20-2008, 10:24 PM
New brushes installed and now the router seems to be running perfectly. Thank you for all the help!

How do you know if the bearings are worn out or not? I'm guessing you would have to remove them to see? I might just have my local service man do them, he said $50 parts and labor to replace the bearings. Seems fair enough and I do not currently own an impact wrench.

jamesgilliam
03-05-2009, 01:11 PM
Well 693k lines into a 705k+ file my PC went quite and was turning alot slower than it should. The air from the cooling fan would not even blow the chips away from the bit. A quick swap with my backup, a little rewrite of the file and I am back to cutting. I am hoping it either dust buildup or the brushes.

mikek
09-14-2009, 01:19 PM
Just had mine quit during cutting. Was only cutting .02" so nothing was hurt, but it won't go! Brushes are OK, switch is OK so it must be the speed control module. It was mostly clean inside.