I have a question about my table saw. It is a 10" Rockwell table saw that
is about 30+ years old. Lately when I run it the motor has been coming up
to speed but then slowing down and speeding up on its own (without a load).
I checked the brushes and they look OK. Any idea what could be causing this
or how to fix it?
Woody
"woodman" <[email protected]> wrote in message
news:fmyQi.999$tX1.614@trndny05...
> It has the original motor. I don't know what type it is, just that it is
> not a separate motor, but instead is integrated into the arbor that turns
> the blade (via a very short 6" belt). Today I disassembled the saw,
> removed the blade and turned it over (table down) and ran the motor for
> awhile. At first it varied speed as before, but after a few minutes it
> started running at constant speed. I guess tomorrow I'll turn it back
> over and see if it still runs constant or varies again.
>
> Woody
>
>
> "Jim" <[email protected]> wrote in message
> news:[email protected]...
>>
>> "woodman" <[email protected]> wrote in message
>> news:PQqQi.972$tX1.498@trndny05...
>>>I have a question about my table saw. It is a 10" Rockwell table saw
>>>that is about 30+ years old. Lately when I run it the motor has been
>>>coming up to speed but then slowing down and speeding up on its own
>>>(without a load). I checked the brushes and they look OK. Any idea what
>>>could be causing this or how to fix it?
>>>
>>> Woody
>>>
>> What kind of motor would that be? Your saw is rather young to have been
>> supplied with a repulsion-induction motoe. If it has a universal motor,
>> it is rather old to have the original one.
>>
>> In the case of the repulsion-induction motor, a failing centrifugal
>> switch would cause this problem. There may be other reasons as well.
>>
>> If you have a universal motor, I don't know. The no load speed of these
>> things is usually limited by friction in the bearings. Perhaps the
>> bearings need replacement. There may be other reasons as well.
>>
>> I would take it to an electric motor repair place. Those guys see more
>> bad motors in a week than we do in our entire life.
>>
>> Jim
>>
>
>
It is a universal motor which uses the direct drive method. This is the
same mechanism used in circular saws.
You could take it apart and lubricate the bearings.
Jim
"woodman" <[email protected]> wrote in message
news:PQqQi.972$tX1.498@trndny05...
>I have a question about my table saw. It is a 10" Rockwell table saw that
>is about 30+ years old. Lately when I run it the motor has been coming up
>to speed but then slowing down and speeding up on its own (without a load).
>I checked the brushes and they look OK. Any idea what could be causing
>this or how to fix it?
>
> Woody
>
What kind of motor would that be? Your saw is rather young to have been
supplied with a repulsion-induction motoe. If it has a universal motor, it
is rather old to have the original one.
In the case of the repulsion-induction motor, a failing centrifugal switch
would cause this problem. There may be other reasons as well.
If you have a universal motor, I don't know. The no load speed of these
things is usually limited by friction in the bearings. Perhaps the bearings
need replacement. There may be other reasons as well.
I would take it to an electric motor repair place. Those guys see more bad
motors in a week than we do in our entire life.
Jim
It has the original motor. I don't know what type it is, just that it is
not a separate motor, but instead is integrated into the arbor that turns
the blade (via a very short 6" belt). Today I disassembled the saw, removed
the blade and turned it over (table down) and ran the motor for awhile. At
first it varied speed as before, but after a few minutes it started running
at constant speed. I guess tomorrow I'll turn it back over and see if it
still runs constant or varies again.
Woody
"Jim" <[email protected]> wrote in message
news:[email protected]...
>
> "woodman" <[email protected]> wrote in message
> news:PQqQi.972$tX1.498@trndny05...
>>I have a question about my table saw. It is a 10" Rockwell table saw that
>>is about 30+ years old. Lately when I run it the motor has been coming up
>>to speed but then slowing down and speeding up on its own (without a
>>load). I checked the brushes and they look OK. Any idea what could be
>>causing this or how to fix it?
>>
>> Woody
>>
> What kind of motor would that be? Your saw is rather young to have been
> supplied with a repulsion-induction motoe. If it has a universal motor,
> it is rather old to have the original one.
>
> In the case of the repulsion-induction motor, a failing centrifugal switch
> would cause this problem. There may be other reasons as well.
>
> If you have a universal motor, I don't know. The no load speed of these
> things is usually limited by friction in the bearings. Perhaps the
> bearings need replacement. There may be other reasons as well.
>
> I would take it to an electric motor repair place. Those guys see more
> bad motors in a week than we do in our entire life.
>
> Jim
>
I greased up the transmission and noticed that a lot of the grease was
coming out of the joints, so I checked all of the bolts and found many of
them loose from years of vibration. I guess that was also preventing the
grease from being fully distributed inside, and once I tightened the bolts
and re-greased, the problem was fixed.
Thanks for your suggestions, Jim.
Woody
"Jim" <[email protected]> wrote in message
news:[email protected]...
>
> "woodman" <[email protected]> wrote in message
> news:fmyQi.999$tX1.614@trndny05...
>> It has the original motor. I don't know what type it is, just that it is
>> not a separate motor, but instead is integrated into the arbor that turns
>> the blade (via a very short 6" belt). Today I disassembled the saw,
>> removed the blade and turned it over (table down) and ran the motor for
>> awhile. At first it varied speed as before, but after a few minutes it
>> started running at constant speed. I guess tomorrow I'll turn it back
>> over and see if it still runs constant or varies again.
>>
>> Woody
>>
>>
>> "Jim" <[email protected]> wrote in message
>> news:[email protected]...
>>>
>>> "woodman" <[email protected]> wrote in message
>>> news:PQqQi.972$tX1.498@trndny05...
>>>>I have a question about my table saw. It is a 10" Rockwell table saw
>>>>that is about 30+ years old. Lately when I run it the motor has been
>>>>coming up to speed but then slowing down and speeding up on its own
>>>>(without a load). I checked the brushes and they look OK. Any idea what
>>>>could be causing this or how to fix it?
>>>>
>>>> Woody
>>>>
>>> What kind of motor would that be? Your saw is rather young to have been
>>> supplied with a repulsion-induction motoe. If it has a universal motor,
>>> it is rather old to have the original one.
>>>
>>> In the case of the repulsion-induction motor, a failing centrifugal
>>> switch would cause this problem. There may be other reasons as well.
>>>
>>> If you have a universal motor, I don't know. The no load speed of these
>>> things is usually limited by friction in the bearings. Perhaps the
>>> bearings need replacement. There may be other reasons as well.
>>>
>>> I would take it to an electric motor repair place. Those guys see more
>>> bad motors in a week than we do in our entire life.
>>>
>>> Jim
>>>
>>
>>
> It is a universal motor which uses the direct drive method. This is the
> same mechanism used in circular saws.
>
> You could take it apart and lubricate the bearings.
>
> Jim
>