Back or front tool

My TCL 125 has no turret .
I was having problems due to "saddle lift" in back tool mode when screwcutting with tool reversed. Reversing spindle and using tool right way up will only give me LH thread unless I cut toward Z+ (away from the chuck)

Now I have made alterations to overcome the saddle lift problem , but it seems to be I would be better doing turning in back tool mode (spindle c/w) , and threading in front tool mode (spindle cc/w)(unless of course I want LH thread )

I have seen this  wiki.linuxcnc.org/cgi-bin/wiki.pl?BackToolLathe

What It seems to me that I need is the facility to change from back tool mode to front tool mode mid program.
Since Back tool mode is called up in the Ini file I cant see how best to achieve this.

Any suggestions folks ?
 

So no takers over the last day or two 
Maybe I havent been clear enough about what my problem is .
maybe try and expand a bit on it 


So atttached is a pic of my is my lathe with two toolposts on the saddle


 

I had been having problems with saddle lifting / jamming (and missed steps ) when I used back tool configuration with cutting tools reversed and counterclockwise spindle.
I have resolved some of the lifting issues with higher voltage at the steppers which allowed me to tighten the gibbs a bit , but clearly better to use clockwise rotation and tools cutting forward taking away the tendency to lift ,
This mode allows me to do beautiful left hand threads but not Right hand unless I cut left to right , from the chuck towards Z+.

But if I use threading tool in the bottom position and spindle counter clockwise, (and in front tool mode) I have my cutting forces in the correct direction and can produce beautiful Right hand threads. Seems natural therefore to use back tool for turning down with reasonably heavy cuts, then go to threading in front tool mode . But how do I do this during execution of a program.

The front or back mode is called up in the Ini file and I cant see a way to change mode without restarting gmoccapy. Surely what I want to do is sensible enough whether for threading or even for parting off. No problems changing spindle direction. No problems specifying a tool offset for any of the front tools . but how do I change the direction of movement for the tools.

Is there a way to change from front to back tool mode mid cycle .

I can inhibit back tool in my ini file
If I then restart EMC without back tool mode I can reverse the spindle and traverses , then operate screwcutting (or parting ) in front tool mode .
Never tried in axis GUI . Have spent too much time setting up the hard buttons to simulate those in gmoccapy. Just feel the need to be able to change modes mid cycle .
Cant be an unusual request surely. Isnt it common practice to part off from the rear when front cutting?

have had a look at that Aciera and initially having difficulty making sense of it but will persevere .
Initial feeling is that it transposes the workspace with an offset.
My problem seems to be that when I go to front tools and I I need the tool to advance into the workpiece, I need to reverse the direction of X negative to move the saddle upwards , when with back tool x negative is downwards.
I dont see how G10 achieves this ( or am I missing something?)

Ist the trajectory aware of the spindle direction?
If not simply use the right tool orientation and let the spindle run backwards.

Or one an negative spindle speed override.

I need to reverse the direction of the tool progression during the generation of the thread Anfanger so simply reversing the spindle does not give me what i need .

Am making mods to the latching relay controls so that machine will respond to M3 and M4 .
Will then look at G10 R180 in the threading routine to see if that gives me what I want !

OK when you use it with spindle synchronized motion its different.
I thought you were using the thread tool conventional and the normal tool in the back.