Re: [CAD_CAM_EDM_DRO] yet another newbie question :)

> I have just recently gotten started in machining. I am using
> sherline equipment and have just about finished my first project, a
> steam engine from the Rudy Kouhoupt video and plans. I am very
> pleased with what I have been able to accomplish thus far. My
> question is concerning CNC. I am having a heck of a time finding
> resources to explain the very basics. Basically what I am looking
> for is a way to "automate" milling of simple shaped items but and not
> deal with the tedium of cranking and cranking where a fair amount of
> material must be removed. Am I way off base here? Should I just
> stick with what I have?

No, you are not way off base. In addition to running complex part
programs, many CNC controls allow you to do what is called 'manual
data input' or MDI. What this means is that you can type in a single
line of "G code" such as "G01 X2 Y3 F2" Which means move from the
current position to X=2 Y=3 in a straight line at 2 inches per minute.
You can also run in an incremental coordinates mode.

However, if avoiding cranking is all you want, you can get that with a
simpler power feed. In the case of the sherline, power feed can be a
stepping stone to full CNC. What you do is buy mounts from sherline
for NEMA 23 size stepper motors. Get 100 to 150 oz/in motors from
Sherline or surplus. Then either get the sherline power feed
controller or buy a stepper controller from www.geckodrive.com or
www.seanet.com/~dmauch and build a little adjustable-rate pulse
generator circuit with parts from radio shack. Later if you want you
can replace the circuit with a PC running CNC software.

Chris