Very nice. But that's a mail order stepper driver, and not what I'm aiming for.
The purpose of this project is to be a stepping stone into the world of computer control. It's not meant to be a truly practical driver design (it actually is, but there are better ones) but merely to allow someone to get to the stage where they admit to themselves, "I can do this!"
To this end I'm designing it from components that should be available at any Radio Shack or RS Components. Darlington transistors, some decent sized diodes, and some pull up resistors. By keeping it simple, I'm trying to make sure people can *easily* build this first step.
That's a big step...advancing from a pipe dream, to a piece of equipment moving under computer control...even if it is only a single axis, and primarily for proof of concept.
My intention is to make a single axis (a CNC primer unit) which, when complete, can function as a reasonable Z axis for a full machine. I figure this is the most "constantly" sized axis of any of them -- relatively speaking the movement is less than a foot, the structure can be easily made strong, and the mounting of a router spindle, or a Dremel tool takes approximately the same "vertical" space.
A relatively small project that can be put to immediate and practical use.
Seems like a good first step for the CNC newbie.
-- Chuck Knight  |