The
first stepper driver I used were "Single Step" drivers
bought from Oatley Electronics. The K179 comes in kit form, very
cheap and works fine for small stepper motors. To get the best results,
the K179 should be used with a constant current source, and fortunately
Oatley also sell a constant current supply in kit form.
The
K142C constant current driver kit includes a fan cooled heat sink
and easy current adjustment. I ended up building my own constant
current supplies from scratch, but for under $30 each these K142C
kits would make life a lot easier.
Transformer based
power supply, with three K179 controllers and home made K142C current
regulators
The K179 is what we call a single step controller. While a single
step controller is fine for small stepper motors, if you want to
get more speed and smoother operation, you need to invest in a half
step or micro stepper controller.
I found my stepper motors would work fine at low speed, but became
unresponsive at higher step speeds. To get more speed, I needed
to spend more money.
Along
with some larger stepper motors, I bought a couple of half step
controllers from Ocean Controls, the KT-5191. The KT-5191 has half
step stepping, and built in PWM current limiting. So a single KT-5191
would replace the K179 and K142C boards.
Half Step stepping made a big difference to my CNC table. Motor
movement was much smoother and quieter.
The
next step was microstepping. I had read about microsteppers, but
they were priced out of my range, usually several hundred dollars
or more per axis. One day while I was browsing the Ocean Controls
web site, I discovered their new range of cheap microsteppers. The
SMC-002 M325 was the cheapest at only $99+gst. The M325 has inbuilt
current limiting up to 2.5 amps, up to 8 steps of microstepping,
and would run at up to 32volts.
