I'm often asked where I get my motors from, or where is a good place to buy
a motor. Unfortunately, I don't know of a really good place,
so whenever I come across a cheap used motor that might be suitable, I save it.
But if you can't wait for a motor to cross your path,
Harbour freight is probably your best bet in the US (or online),
and in Canada, it's probably Princess Auto.
Or you could buy a
cheap dust collector just for the motor.
But because I'm asked where I get my motors so often, here's some
of the motors I used for projects and where I got them from.
This is a 1/2 hp 1750 RPM furnace motor, which
I use on my 16" bandsaw.
Not sure where it's from, probably a yard sale.
Another belt driven furnace motor on my strip
sander. I think I picked this one off the curb on
garbage day.
The old belt-driven furnace motors were great to reuse,
but since the 1980s furnaces have all been direct drive.
All my belt driven furnace motors were from when somebody saved
the motor when their furnace was replaced, and then, years later,
threw it out or sold it at a yard sale.
A 1/2 hp motor on my lathe.
This one was a lucky find on garbage day.
A 2/3 hp motor on my small
dust collector. I bought
a really crappy table saw for $20 just for that motor.
Unusual for a crappy table saw was that it had an induction
motor. Most crappy table saws have universal motors,
unsuitable for homemade machines.
A very heavy 1.5 hp motor on my first homemade
bandsaw. This one originally came with my lathe.
(which now has the 1/2 hp motor on it shown above)
A 1/3 hp pump motor. This one I picked out of a dumpster
behind a Home Depot, then removed the pump. I used
it on my apple grinder
and later on my homemade lathe.
A 1/4 hp utility motor powering my buffing wheel.
This one came from a yard sale.
A 1/4 hp motor powering my horizontal boring machine
This motor came with a very simple homemade
metal lathe I inherited.
A 1 hp pool pump motor on my
14" bandsaw. My
neighbour put this on the curb. The thermal fuse
was blown, I replaced that fuse with a piece of solder.
A clothes dryer motor, from my brother's old dryer.
Surprisingly powerful. I built a blower with it.
That motor could work for a small bandsaw too.
Motors from clothes dryers and top loading washers are good to reuse, though it
can be hard to mount the right kind of pulley on them, and if you take them out of
the washer without figuring out how it's meant to be wired, it can be hard to figure
out the connections after the fact.
Motors from front loading washers are universal motors,
and unless you know how to hook up a speed controller to one, unsuitable for
most homemade machines.
A direct drive brushless DC furnace motor. Unfortunately,
I don't know what wires control what signal for this motor.
A regular direct drive furnace motor would be easier to use.
This is a 2/3 hp motor from a crappy Craftsman
tilting head bandsaw that was
too frustrating to
try to fix. I saved the motor.
A garage door opener motor. Supposedly 1/2 hp.
The problem with these motors is that they aren't
made for continuous operation, so not recommended.
A 1/3 hp sump pump motor. Very suitable.
And a stack of motors in my stash. I guess I am
a collector of motors!
With random motors from different places, figuring them out can be a challenge.
I made a video figuring out one random specimen of motor. But unless you are
knowledgeable about induction motors, this video probably won't help you much,
but it gives you a sense of what might be required to figure out some random motor.
Don't use universal motors
Most induction motors are suitable for homemade machines.
However universal motors
are much less suitable. Universal motors are found in hand held tools,
jobsite table saws, kitchen appliances, front loading washers, treadmills,
and vacuum cleaners.
However, anything that needs to run quiet and for a long time tends to be
an induction motor (or sometimes brushless DC motor). These motors are typically
found in large appliances that are part of the house or need to run unattended.
This includes furnaces, refrigerators, dishwashers, clothes dryers, air
conditioner outside unit fan motors, and sump pumps.
Refrigeration compressor motors are also induction motors, but they can't
be reused.
There are a lot of places where suitable motors can be found, so if you are even
remotely thinking of building a bandsaw, belt sander or other homemade machine
and you come across a suitable motor, keep it! Even if it's only 1/4 HP,
that could be enough for a bandsaw or sander,
at least until you come across something better.
That said, never use an under-powered motor for a dust collector. Without enough
power, it won't even come up to speed, and the overloaded motor will soon burn out.