In a message dated 97-10-01 09:40:55 EDT, you write:
 
> I got this idea when I read your posts about extractors.  What if you put a
 
> switch on your motor, kinda like the dimmer switch you use on lights?
 Maybe
> it could cut the power and make the motor run slower, then as you turn up
the
> switch the motor would increase in speed????  I'm not electrically
inclined,
> but it might work.  Just my thoughts on it.
>
CAUTION!  Do not use a light dimmer on a motor.  The type of dimmer commonly
used on lights will burn out and possibly damage the motor.  They are not
designed for "inductive loads" which is what a motor puts out.
 
You can buy something called a Variac to vary motor speeds.  They are large
variable transformers and quite expensive when new but have been made for
many years.  A used Variac to handle a 1/2 HP motor should be $50 to $100 if
you can find one.  (Try the Web)
 
There are also variable speed motors and controllers both AC and DC but they
are usually several hundred dollars.
 
The two speed furnace motor sounds like the most economical idea.
 
Tom Harker (electronics design & hobby beekeeper)