Re: [CAD_CAM_EDM_DRO] Re: Router life, getting better bearings,

Well I don't know about design life for anyone router, but can offfer a
few observations.

First I have to agree atleast a bit with your Router repair person.
It is fair to say that almost all handheld tools with universal motors
should be considered intermittant duty tools. That does not mean
though that they are designed for only 100 hours of use, some of the
imports may be, but I hardly believe that is the case with the PC. As
far as I'm concerned is is a feather in PC cap that they have router
motors that hold up as well as they do in continous operation with only
bearing failures. I'm surprised that they don't limit there warranty
with repsect to this.

As far as the bearings themselves go a 100 hours on grease loaded
bearings at high RPM may be pretty heavy duty. That would depend alot
on the design of the bearing, its preload, operating temperature, grease
and probally a host of other things. It should be noted that machine
tools running high speed spindles often use oil or oil mist
lubrication. Now bearings like almost all things are continously
evolving, it would not hurt to go to a bearing supply house and get a
second opinion on what is available for hi speed and loads. Just
don't get your hopes up that anything will work better in your
application than the PC installed bearings.

One thing to consider is installing the bearings your self and doing so
on a regular basis. This would save the down time associated with
taking things back to the repair house and would allow you to
experiement with other bearings. You could even experiment with
differrent lubrication types. In the end though I thnk you will find
that your best results will come form using off the shelf high quality
bearings.

Thanks
Dave



thorcnc wrote:

>Hi David,
>
>Good points. I'll be taking router #2 in next week for the
>replacement of the bearings complements of Porter Cable. I'll ask to
>see what wore.
>
>When I took my first router in the guy at the shop, who seemed very
>knowledgeable about rebuilding tools, said that almost all of the
>routers are only built for 100 hours of life. Most users only turn
>them on for a few minutes, and then shut them off. I asked him about
>Bosch and Makita, and he felt the Porter Cable is at the top of the
>quality scale (for single-phase). He said all have about the same
>life on their bearings.
>
>Have others out there found this to be true?
>
>Thanks,
>
>Brent
>
>--- In CAD_CAM_EDM_DRO@yahoogroups.com, "David A. Frantz"
><wizard@e...> wrote:
>
>
>>Hi Brent;
>>
>>Before you can make a determination about buying higher quality
>>
>>
>bearings
>
>
>>it would help to know why the originals failed. I would ask for
>>
>>
>the
>
>
>>orignal parts back or rebuild the next one myself so that I could
>>
>>
>get a
>
>
>>good look at the bearings. Plus I'd want to make sure that it
>>
>>
>is
>
>
>>actually the bearigs that have failed and not the mounting
>>arraingement. Wearing out after a 100 hrs seems pretty bad on
>>
>>
>the
>
>
>>surface but we don't know all the ins and outs here of what
>>
>>
>happened to
>
>
>>the motor.
>>
>>Thanks
>>Dave
>>
>>
>>