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

Ballendo,

This WAS helpful. Your email of yesterday on configuration and MaxNC's
"phase outputs" reminded me that I have a selectable set of phase
outputs also! I checked ACODE.DAT, and discovered that I HAD used a
"reverse rotation" pattern for the Y axis (motors SHOULD be wired the
same, and the Y axis uses a left-hand thread). I selected a reverse
rotation pattern for Y in my program, and with the exception of also
flipping the direction of the UP and DOWN keys, the travel, sign and
usage works the same for my program and MaxNC (well, I use the arrow key
set, and MaxNC uses just left and right shifts). Panel encoder (jog)
also stays + for XYZ axis!

And I also "discovered" that the + & - keys work well for the 4th axis.
Yes, I allow '_' and '=" as aliases for the '-' and '+' keys! So I'm
down to getting the 'increment' an 'commanded' operations on the rotary
table (I've been testing B) to indicate (the little pointer on the
circumference) the right direction on the table! Sounds like I should
try C first, if table faces the un-involved axis.

there's also something "funny" when reading compass cards, as I
recall. The numbers on the circumference read backwards?

more below :>)


ballendo@... wrote:

>
> 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.

Just thinking that rotation is opposite for the tool helps, I was
wondering how to envision the tool going in circles! And I get the
"positive direction of the uninvolved axis" now. Ouch!

>
> 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.

Both hugh? Well, if I command 2.00" on Y, I get + movement (tool to
rear of the part, yes). But currently, if I command 200.0 deg on the B,
the table rotates ccw to 160 degrees (according to the indicator).
Which I don't think I want! But then the "tool" went to 200 deg!?
OUCH! Which do I want?

Would I really use G02 and G03 on the table? It would be nice to be
able to get it to "rotate a cut", I've got a part I'd LOVE to cut that
way (remember the crankshaft plates I had to cut as quadrants?).

>
> 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.

Yeah, I'll take a while to "digest" that.

>
> 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).

Configurations are a GOOD thing, I just don't want to have to change the
phase outputs or feed rate calibrations.

>
> >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 :-(

Yeah, I can see why. I was of that camp for quite a while, 'till in '92
I had to support multiple languages in a product, and WordStar couldn't
accommodate the "funny characters" in my foreign language strings!
With another programmer supplying some macros, I switched to Underware's
"Brief" in about a day. Never looked back!

>
> 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...

Yup! Good thing to call them! I wish MaxNC had done it that way. I
HATE the "CAPS LOCK" approach. Well, and also the choice of keys for
commands, and EXITS, that's what the ESC key is for!

Good information! Enjoyed thinking!

tnx, Alan KM6VV

>
> Hope this helps.
>
> Ballendo (who's praying he typed it right)