G84 without spindle feedback

Hi,
Is it possible to use G84 without spindle feedback ? Floating holder is used. Now when
"M03 S100
G84 X100. Y100. F300 R3 Z-40
"

is issued machine moves to R3 but that is it Z-40 is not done.


Tero

It looks like the majority of the useful code is #if-0-ed out:
github.com/LinuxCNC/linuxcnc/blob/master...nterp_cycles.cc#L236
That isn't going to work without recompiling, and then there would be no guarantees that it would do the right thing.

Might be interesting to try it. Perhaps the chap who wrote it just don't have a tapping head?

I will try it. Is it possible to add this feature to Master?

Tero

I did try releasing G84 of comments but I got this:

image missing http://i170.photobucket.com/albums/u243/terokaarlela/Kuvakaappaus%20-%2020.09.2016%20-%2014.46.26_zpsj6k1ljaf.png

It seems thread pitch is not brought into funtion convert_cycle_g84 at all. It is defined with F300 in G84 function. And it should produce 3mm/rev for START_FEED_SPEED_SYNCH. Or should I comment that line out? We have 100 Rpm and feed of 300mm/min that should be enough for floating tapping.

Tero

I tried:

START_FEED_SPEED_SYNCH(3, 0);

And now machine moves to position and remains at R-level no alarm but no Z-40 movement either. How to go forward?


Tero

This should be in form:
CHKS((direction != CANON_CLOCKWISE),
NCE_SPINDLE_NOT_TURNING_CLOCKWISE_IN_G84);

cycle_feed(block, plane, x, y, bottom_z);
STOP_SPINDLE_TURNING();
START_SPINDLE_COUNTERCLOCKWISE();
cycle_feed(block, plane, x, y, clear_z);
STOP_SPINDLE_TURNING();
START_SPINDLE_CLOCKWISE();

I will try to get it working tomorrow. It seems someone has worked on this years ago but it is not yet merged in master:

git.mah.priv.at/gitweb?p=emc2-dev.git;a=...826d8ff000ff37a03fb3

Tero