Re: Z axis Offsets

[Ray <rehenry-at-up.net>]

Tim

I've been holding off here a bit -- wishing for a more definitive answer.  
Here goes -- perhaps nothing.

I posted last week about my problems with an A axis and the g92 offset 
command.  Tkemc uses emc_mdi g92 #.#### when you ask for an offset from 
the popup.  All that tkemc does with this is prepare a string with the 
correct information and pass that string to emcsh.  More than this, it 
seems that it does exactly the same thing for any axis.

I'm wondering if the problem is related to the last axis defined -- your 
Z, my A.  You might try adding an extra axis to your ini.  Just copy one 
set of axis defintion variables and change the [AXIS #] at the top of that 
bunch to the next one.  If you have real limits and home switches, you may 
need to change those definitions for this imaginary axis before you start 
up.

Now change the following parameters in the [TRAJ] section to read

AXES =                  4
; COORDINATES =         X Y Z R P W
COORDINATES =           X Y Z A
HOME =                  0 0 0 0
 
When you fire it up, you should see the extra axis position display on 
tkemc.  Ignore it.  Home out the others and try entering a z offset and 
see how it does.

IF z-offsets work like x and y we have narrowed down the nature of the 
problem.  

IF they don't, and you run the emc from a terminal rather than the icon by 
itself, pull down the config menu and click on debug.  Select "command 
issuing,"  "NML," and "interpreter."  Start the emc, home out, and set a 
small offset (2") in each axis using the popup.  Then reset them to zero 
using the popup.  Copy all of the text from the terminal window and send 
it to me off list.

Thanks for all your work here.
(haven't tried jog in xemc -- perhaps later)

Ray


On Friday 28 September 2001 05:53, Tim wrote:
> Been doing a little work with Bridgett using BDI 1.09 with Ray's
> 8-1-2001 tarball replacing the original BDI EMC. Using steppermod as it
> is much easier on the computer with the 10000 steps/in and 120 ipm
> rapids I am getting with the Gecko G320 drives. Was trying to use tkemc
> and kept running into a problem with not being able to get an offset to
> reliably work on the Z axis. Seems to work great on X and Y. I tried
> doing the offset by both a G92 and by right mouse clicking on the axis
> display. Sometimes the offset will take and the numbers change, but more
> often than not they don't change. Even when they do as the offset is
> frequently ignored when I run in auto mode. The X and Y axis are not
> displaying this behavior even though I am doing exactly the same thing
> with them.
>
> Switched over to xemc and the problem totally disappeared and the M2 at
> the end of the program does not cause the offsets to reset. I did notice
> in manual mode that with xemc I can only jog if I set the jog distance
> to continuous. If I set it to an increment nothing moves when I press
> the key.
>
> Much happier now that I am back home again with EMC instead of getting
> frustrated with DeskWinNC.
>
> Tim
> [Denver, CO]

<older message snipped-ray>