Stepper motors, encoders...

[runnoahrun]

I'm a new guy wishing to build my first CNC mill. I aquired 3 450oz Superior Electric "slo-syn" stepper motors. Questions on encoders, should these have built in encoders? What should I look for? I also need a controller, is the 3-4 axis controller from www.hobbycnc.com something that would work with my motors? Also, if the motors are 200 steps/rev, where do I tell the computer what pitch the lead screws will be to get accurate results (is this what encoders do? I'm new).
Thanks,
Noah

[ger21]

1.You don't need encoders with steppers.
2. With that size motor, you'd probably want to use Geckos.
http://www.geckodrive.com (lot of good information there, too)
3. Use either TurboCNC or Mach2 to run the machine, that's where you set up your leadscrews/steprate/etc...

Gerry

[MATT40]

RUNNOAHRUN
I JUST GOT THE SAME MOTORS BUT 700OZ-IN
WHAT IS THE 200 STEPS PER REV
WILL THAT SAY ON THE MOTOR TAG
ALL THESE ONES SAY IS
TYPE SS700
RPM 72
120 V
1.0 A
50/60 HZ
SPEC A202161 /// CAN ANYONE HELP

[fyffe555]

Matt40,

Are these three lead motors? If so, what you have there are 110 volt AC Synchronous constant speed motors with a fixed speed of 72rpm. Not Steppers or Servo's. Not the sort of thing you need for home built variable speed CNC.

I think I've seen them run as a DC stepper motor on a pick and place machine but you still have a low rotational speed and the drivers to provide phase shifting will be tough to find and expensive and probably not compatible with step/direction software .

[MATT40]

FYFFE555
SO WHAT YOU ARE SAYING IS THAT I NEED HI RPM'S AND WHAT RPM DO I NEED. THE END PLATE SAYS SLO-SYN / STEPPER MOTOR
THIS MOTOR WILL NOT WORK ? OR WILL IT IF I GET STEP/DIRECTION SOFTWARE FROM SUPERIOR ELECTRICS
WHO MAKE THE MOTOR
P.S. THE MOTORS WERE A FREEBIE BRAND NEW

[fyffe555]

Matt40,

First off, How many leads does your motor have, if it's three then its a Slo Syn SS700 AC synchronous motor - If the name plate states 110v 72rpm than that's what you've got. Do a google search for the specs, I couldn't find a slo syn ss700 stepper, if it doesn't stat how many degrees per step ( 0.9, 1.8 etc) or steps per revolution (200, 400, 60 etc) then it's not a regular stepping motor.

The step/direction software will not come from the motor manufacturers, its a group effort between your cad/cam software and what ever you choose to run your system with.

Before saying what rpm's you need I suggest you spend some time reading up on some of the excellent threads here by people more knowledgable than me. YOu'd need to understand the process and components of the CAD and CAM software, G-Code, 'system' software like Turbocnc or Mach2, motor drivers, Power supply and motors, the leadscrew and gearing they provide. Once you have decided what you want to d then its easier to figure out what you eed and the speed required.

As an example I use Turbocad and rhino for cad model drawing, ace converter and meshcam to produce the g-code, Turbocnc to run the machine and turn the G-code into movement, home built and IMS drivers powering the motors running 1/4 and 1/8th step, Pacsci p21 110 oz/in motors and 1/2-10 leadscrews. At 600 rpm that gives me 60inches per minute. and 16000steps per inch per axis

good luck..

[MATT40]

FYFFE555
THANK FOR THE INFO
CAD/CAM THAT I WILL USED IS MASTER CAM
BUT I WILL READ SOME MORE AND ASK SOME MORE
BEFORE BUYING PROPER MOTORS. PRICE IS NOT TO MUCH OF A PROBLEM BUT QUALITY SHOULD BE GOOD . I NEED TO CUT AT ABOUT .05" DEEP ON A CNC ROUTER THAT I AM DESIGNING
I HAVE 1 BALL SCREW , LINEAR SLIDE BEARINGS FOR A START.
AND I WILL GO FROM THERE. THANK FOR YOUR INPUT AND HELP
LOOK FORWARD TO TALKING TO YOU SOON