MESA 5I25 7I77 CAN DRIVE THIS MOTORS??

Thanks for the info
i try the calculate scale buton
is it working??

it is basic math, and I often find it simpler just to work it out myself.
I can't say as I've tried to use the scale calculator in PNCconfig, but the one in StepConf usually confuses the heck out of me, and I rarely get it right the first try.

The INTERMAC 15OO machine i m trying to retrofit is a 4axis gantry machine with double motor on Y and C axis.
In the C axis the motor is mounted in planetary reducer and then to a pulley.The reducer have no ratio data
Is there any other way to calculate the encoder scale?.
Also for the configuration of the gantry i understand that i have to manually edit the HAL file.
After the edit can i reconfigure the file with the pncconf wizard

If you have it, you might be able to glean that info from the configuration or parameter info for the original control. (at least the encoder counts/degree or rev.)

Often the encoder's line count is somewhere on its id lable, but you still have to figure out your planetary's reduction (might be in it's model description) and any other reduction from belt or chain cogs.

For a dual motor gantry config, right now it is advisable to use the development branch of Linuxcnc, aka Master (2.8-pre) rather than the general released version (2.7). As it is much better suited to configurations where joints 0,1,2,3... don't necessarily equate to axis x,y,z,a... Such as for a simple duel motor gantry or more complex non-trivial kinematics.

If you use pncconf after you've made any hand edits, it will overwrite them. So, if you must rerun the wizards, backup your old files first.

What is the procedure to install the linuxcnc aka Master (2.8-pre)
is it a stable version?

That depends on what you mean by stable. "Stable" in the LInux software world means that a programs development has been frozen, most of the bugs have been worked out, and new features are no longer being added. For the most part Master will run reliably, but it is the development branch where new features are introduced and the bugs are worked out. There are a lot of people who run Master on machines. But if you are regularly updating your software there is no guarantee that the next update won't introduce a bug that may break your configuration. There is no schedule for a release date for when 2.8 will be released as a "stable" version. For the most part I discourage running Master on a production machine in a factory environment unless it has a feature that is necessary. (where the machine operator is not the integrator) But for a personal machine where the person who set it up is the one who runs it, there is little problem. Just keep a close eye on machine operation for a while after any software update, but truly nasty surprises are rare..

If you installed from the current Linuxcnc iso then you should only need to enable the Linuxcnc Buildbot Master repo in Synaptic, then mark all updates and then update.