Pages: [1]   Go Down
Author Topic: Stepper motor help...cnc  (Read 2667 times)
0 Members and 1 Guest are viewing this topic.
0
Offline Offline
Newbie
*
Karma: 0
Posts: 36
Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

hey guys i am looking at buying 3 stepper motors. I have been doing some research and i have found these . http://goo.gl/11tov
My question is are these 3 motors enough to work a cnc mill? For starters i will be using just a dremel (I know not the best but will have to do for the moment) so i will not have to worry about much weight.
Could some one help me kinda fill in the gaps? also i think if i researched these right these can turn counter and clock wise...? I also have this from a driver board....http://goo.gl/71rfE


Thank you for your help
kelly


PS: Remember this is my first cnc does not need to be fancy!


 
Logged

USA, FL
Offline Offline
God Member
*****
Karma: 14
Posts: 689
A life? Where can I download one of those?
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

First thing is that driver board you linked doesn't have the current rating to run the stepper you linked.  You would need the "BigEasy" board, https://www.sparkfun.com/products/10735?.

Next you could Google RepRap, it's a DIY CNC machine.  Might give you some insight.

Oh, and there's no need to shorten you urls here.   smiley-wink
Logged

//LiNK

0
Offline Offline
Newbie
*
Karma: 0
Posts: 36
Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Hey thanks for the reply i just saw that the power did not go low enough for the stepper motors, did not have time to update.
Logged

Offline Offline
Newbie
*
Karma: 0
Posts: 9
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Hi,

I just started with Arduino yesterday and I am having fun.  While looking for a post about writing/reading to registers on the "Due", I saw your post about steppers for a CNC.  I have 25 years experience with steppers (see, e.g., U.S. Patent 599,0640) and I will be making a special driver board to interface steppers to the Arduino later this year.  I also ran a machine shop for 15 years, milling aluminum and steel.  You first have to differentiate between the motor for the cutting spindle (typically a large horsepower 3 phase AC motor) from the motors for 2-3 axis positioning.  Cutting motors need plenty of torque and speed and steppers are not desinged for this work.  As for X,Y, Z positioning, steppers are generally not used commercially because they are not fast enough and/or the steps are to large to obtain high accuracy (.001" or better) [Gear reduction adds too much error.]  The typical CNC will use AC servos with high resolution optical encoders (A, B + index) for positioning, but DC servos can be used in some circumstances.

If you want to use steppers, you need to look at the torque curves for the motor and see if that will meet your needs.  You would want to use a bi-polar motor in half step mode (this requires a different timing sequence on the H bridge signals than full step mode).  You can also use a microstepping driver.  I would be glad to help you further.  You can email me at pwyer@aimcontrols.com.

*** If anyone reads this, I am looking for functions to write/read registers on the "Due". I want to set up the real time clock and the pwm mode on the 32 bit timers/counters.  If there are none, is anyone interested in working with me to create a library of functions for this purpose?
Patrick.
Logged

USA, FL
Offline Offline
God Member
*****
Karma: 14
Posts: 689
A life? Where can I download one of those?
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

There's a specific forum for the Due.  Might post over there to create some interest.  I know that they are hungry for libraries for the Due.

http://arduino.cc/forum/index.php/board,87.0.html
Logged

//LiNK

Pages: [1]   Go Up
Jump to: