"sailor" wrote in message
ups.com...
Charley wrote:
Delta "Unisaws" do not use 1 hp motors and their motors don't have
brushes
either. The smallest motor that I've ever seen on a Unisaw was 2 hp and
all
Unisaws were manufactured with induction motors and they don't have
brushes.

If your non-Unisaw motor has brushes, then the problem is likely to be
bad
bearings or worn/damaged brushes and a bad commutator (the contacts on
the
armature that the brushes rub on). If the motor has been over heated and
the
windings have been damaged, then this is also a likely cause of your
problem. Does the motor have a bad burning smell to it? Did it smoke the
last time that you used it? If so, it's time to go shopping for a new
motor
or maybe a whole new saw. If not, then you can have the commutator
cleaned
and dressed (resurfaced) and then replace the bearings and brushes and
your
saw should run OK again. All of this work is best done by an electric
motor
shop or dealer service facility, if you haven't done this type of work
before.
--
Charley


Charlie, just wonderin where you got your Unisaw info from. I've only had
the
saw for a short while, and from what I read, in the groups, it sounds
like is is an
orig. 1 hp motor. Aparentlly is called a repulsion-induction motor, and
the brushes
are used for starting. This motor has brushes, and says delta on it. It
says 1 HP.
And the switch plate says Unisaw. It's looks almost exactlly like a
friends, except
that this ones base is cast iron. It was made in 1946. It even smells
lkie a Unisaw,
sooooooooooo it's a Unisaw.

The motor doesn't smell, or smoke. It's like the run circuit doesn't
kick in and the
start circuit keeps running.
That's assuming there is a start and run circuits!

Thanks for the ideas.

Cliff

Charlie was talking about "modern" (i.e. those made in the last 40 years or
so) Unisaws. Those sold these days have 3hp or more motors.

Repulsion-induction is short for repulsion start induction run. This design
takes advantage of the fact that a series wound DC motor will also start and
run on AC.
At startup, brushes conduct electricity to the armature. When the motor
speed gets fast enough, a centrifugal switch withdraws the brushes. From
that point onward,
the motor acts in induction mode. It is possible that the brushes do not
retract; thus the motor does not enter the induction mode. You should take
the motor to a repair shop for investigation.

High maintenance is the principal reason that repulsion-induction motors
fell out of favor. These motors have the lowest starting current, and that
is their principal claim to fame.

Jim