Back or front tool

Note:

using:
> KINEMATICS = trivkins cooordinates=XYZ
assigns x==joint0, y==joint1, z==joint2


alternatively, using:
> KINEMATICS = trivkins coordinates=XZY
would assign x==joint0, z==joint1, y==joint2
and could be helpful in updating halfiles since
it would preserve prior joint0,1 connections.

No connections are required for dummy coordinate y==joint2
but a [JOINT_2] stanza with immediate homing is probably
required to use "HomeAll" provisions.


Ref (trivkins):
linuxcnc.org/docs/devel/html/man/man9/kins.9.html
> trivkins - generalized trivial kinematics Joint numbers
> are assigned sequentially according to the axis letters
> specified with the coordinates= parameter.

Ref (immediate homing):
linuxcnc.org/docs/devel/html/config/ini-...ml#_immediate_homing

Thanks Guys ,
I now have turning on back tool followed by singlepoint threadcutting on front tool.

I homed X, and Z using my hard "home all" button but it did not show as homed until I clicked on the screen home button , then I was able to click on Y home button and it then showed as homed .
The DRO does show an active Y axis too . Can this be inhibited ?

I have to admit I am not quite following the info which your links guide me to Dgarrett

Have played a bit with this . . Bit of a voyage of discovery but am delighted it works . Thanks again guys .

Took a bit of getting used to . Had to reset my tool offsets and of course you need to do a G10 roration in MDI, (in order to place the machine in the right mode) before calling your tool change , then setting the offsets . All a bit novel for me but I will get there !

I found that once I had set the offsets, each within its appropriate rotation for front or back, I still had to touch off within each rotation . Seems logical enough but had me wondering initially.
In the tool table there is the option to nominate tools as back or front . Does this have any effect on this process

john11668 wrote:

In the tool table there is the option to nominate tools as back or front . Does this have any effect on this process
 

Front and Back in the tool editor are the front and back angles of the insert, so that you can have a representative image in the preview (also, at least some implementations of G71 use the front and back angles to avoid gouging) 
 

So hardly going to affect me yet but thanks Andy.
What I am struggling to find though is how to reverse my spindle .
Both M3 and M4 currently send the spindle in the same direction. Its a DC motor so I can reverse by reversing the motor leads anyway
So as my normal operating mode would be back tool (slant bed lathe) I am presuming i would choose CW as M3 direction,
So then I call M4 and I want spindle to run CCW . Bob relay starts my spindle and Bob analogue output regulates my speed, but I need to energise my reversing relay to change direction .
I have a 4 relay additional board so I can choose any one to energise my reversing relay but I just cant find what I need to write into my Hal to make it happen.
I have all the output pins for axes A and B to choose from
My Hal files are at the top of this page so if anyone can guide me I will appreciate this