Re: RE: more R,P,Y axis conventions (rotary)

Alan,

Thanks for the kind words.
(More comments mixed in below)

>The MaxNC code and motor wiring/... are fine (rotary table subs for
>Y, wasn't sure WHICH way it SHOULD rotate).

Right hand rule: First, you'll notice I haven't stated the "right
hand" part of the right hand rule! That's because I have always found
the text descriptions puzzling!

So what I've done is "distill" the rule into a truth which can easily
be written and understood. This is:

To determine whether the motion of a rotary axis is clockwise(CW) or
counter-clockwise(CCW); Look at the TWO axes involved in the rotation
FROM the POSITIVE DIRECTION of the UNINVOLVED AXIS. And pretend you
are looking at a clock from this vantage point. That's the right hand
rule!

For example, let's put your rotary table flat on the mill table,
under the spindle. This will make it a C axis (rotates around Z). Now
the plane of the rotation (G17) is defined by the X and Y axis (they
are the "involved" axes. Which makes Z the "uninvolved" axis.
Positive direction for Z is Up. The sherline you have is small so get
above it and look down on the rotary table (you are now looking at
the INVOLVED (XY) axes FROM the POSITIVE DIRECTION of the UNINVOLVED
(Z) axis! So TOOL movement CCW and CW is easily determined. The
rotary TABLE will move the OPPOSITE direction so that the TOOL moves
correctly.

Here is where it gets REAL confusing! WHICH is the POSITIVE direction
of rotation? Answer: BOTH!
With G02 it will be positive when the TOOL is moving CW.
With G03 it will be positive when the TOOL is moving CCW.

Instead of risking confusion, I'll stop here and let this sink in.
You see, it's not hard to wonder which way the rotary TABLE
is "supposed" to move! But there is enough info above to ALWAYS be
able to figure it out.

Next question:

>That was my plan, I hate having to change config's (I'll forget).

Actually, having different configs can be VERY useful. You can easily
set the machine up for different materials, for example. Or different
configurations (like with rotary or without).

>I think I've got that down, So is it tool movement on the rotary
>table also, or rotation of the table?

TOOL movement. If you got here by reading, you already knew that :-)

> Yes. OR's work well for flippin' bits...

>>OR for 'C', we call it an "EXCLUSIVE OR" (up carat).
>>Don't remember what it was in BASIC, the words "AND", "OR" and ???
>>"XOR" ??

Yes. XOR, missed the X... Duh!

>Yes, long, long time ago, we used U,D,L,R, in WORDSTAR.

DeskNC still does! I wish he'd support the "common" keys! LOTS of
programmers WONT let wordstar go :-(

BTW, I call these the "common keys":
cursor(XY) and PgUp/PgDn(Z) and +/- for fourth axis. Yes, it can work
on the "top row" keyboard, ya just need to treat the =(equals) as a
plus also(for the guy who forgets to "shift". It's just a coupl'a
addt'l scan codes...

Hope this helps.

Ballendo (who's praying he typed it right)