Re: [CAD_CAM_EDM_DRO] Indexer

On Fri, 9 May 2003 15:54:16 -0400, you wrote:

>Hello,
>I'm new the post and have been learning quite a bit, although sometimes with
>tears in my eyes as I realize how woefully ignorant I am about electronics.I
>do mechanical design,manual and CNC machining for my real job.
>
>I plan to build a CNC router for home soon, and have been watching the
>chunks of info flying over my head.Trying to catch the small ones though.
>Got to start some where I guess.
>
>Right now I am designing a rifling machine for muzzle loaders, and I need to
>intermittently index a shaft 120 degrees of rotation.
>
>Does any one know of a simple method (meaning cheap and or home built) of
>using a stepper motor and some type of controller that will cause the motor
>to rotate 120 degrees and stop, every time a limit type switch is depressed?
>Or some other method?
>
>I also need to activate a solenoid every 3rd touch of a switch or other
>electronic activating method.
>
>Any help gratefully accepted! Thanks! Steve
>

Low RPM gearmotor, DC. Get two microswitches, put an index plate on
the same shaft as the gearmotor, and get a small solenoid. You want a
mechanism that allows a pin to ride on the edge of a wheel, and drop
in to lock the wheel in place. When it does, it cuts off the motor.
Pushing the button pulls out the pin (solenoid) and holds the motor on
when the motor rotates. A slight delay will allow the pin to get
fully out. Spring load the pin so that it drops in. A second
microswitch will activate once per revolution.

This is slanted to mechanical design, so the electronics is really
basic.

It is a rather crude CNC.


Harvey