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woodchucker[_3_]

On 5/22/2013 2:42 PM, wrote:
On Wed, 22 May 2013 12:58:12 -0500, Leon lcb11211@swbelldotnet
wrote:

On 5/22/2013 11:59 AM, wrote:
On Tue, 21 May 2013 20:09:10 -0500, Leon lcb11211@swbelldotnet
wrote:

On 5/21/2013 7:55 PM, wrote:
On Tue, 21 May 2013 13:47:21 -0700, Pat Barber
wrote:

On 5/16/2013 8:20 PM, Gramp's shop wrote:
I'm considering using this set up for panel-raising operations. While I recognize the speed issues using a PC690, I seem to recall that there are speed reducers available, oui?

Yes...there are speed reducers but they are not good for the
router motor.

If you are going to raise panels with a 690, use a vertical
panel raiser.

I think a router table needs a variable speed router for
typical work and that includes big ass panel raising bits.

How is a variable speed control bad for a universal motor when a
variable speed control on a router (with a universal motor) isn't?

Think your way of working before you purchase.

I can offer that an external speed control is typically rated for "X"
amperage, often much greater than that of the unit is regulating.

Typically routers with built in speed control also have the ability to
monitor the router speed and give more gas with it senses the RPM's
slowing down. External speed controllers are not a whole much more than
a dimmer switch for your lighting and do not monitor speed control.

I have both, I used an external on a 15 amp single speed router and
while it did control the speed while running unloaded if you added a
load you had to adjust accordingly. With a built-in speed controller it
tends to maintain the RPM's to a constant up until you exceed the
capacity of the router.

Not sure I buy that but how is that bad for the motor? As long as you
don't stall the thing, there shouldn't be any problems.

Think about a router running at at half the speed under a load with
reduced available power. Working harder, spinning slower, fan not
keeping up with heat being generated.

Not buying it, at least until the motor stalls. Universal motors
aren't like induction motors, which do have a negative resistance and
will attempt to maintain RPM at any load (or voltage) until they burn
up. There is some increase in current due to the reduction in
back-EMF but it's not that huge. Whether the control is internal or
external doesn't change this.

I would have to agree with that.
The internal units don't protect from heat. they keep the performance
optimized..

But on the other hand isn't that controlling voltage.. so maybe I don't
agree. Wouldn't a dimmer(voltage control) lower the voltage, while the
feedback unit, under load would increase the voltage (good) whereas the
dimmer approach pulls more amps at a lower voltage (bad)....

I'm not sure where I stand now.. :-)

--
Jeff