Pat Barber writes:
On 5/22/2013 11:42 AM, wrote:
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.
Since other folks actual experience is not acceptable, why not just
go your own way with a speed controller and let us know what you
found out ?
I suspect that regardless of whether a speed controller is damaging
to a router, it really depends on the usage model (duty cycle) of the
router. Using a speed control to do a half-dozen raised panels over
a 12-month period is quite different from using a speed control in a
cabinet shop to raise panels every day.
FWIW, I've used a speed-control on a PC690 when spinning a large
horizontal panel raising bit in a router table. It worked fine and
I've not had any problems with the router in the intervening decade+.
Today, I use a Delta HD shaper instead.
scott