pauseAtZ plugin: Support re-homing X and Y before restarting

In a two-colour print, the operator has to mess about with the X
carriage to swap the filament in the print head, which can disturb the
X position.  In other applications of pauseAtZ, the operator needs to
interact with the workpiece, perhaps disturbing the Y position.

So support homing the X and/or Y axes just before resuming.

The default head park position of [150,0,] is suitable for use for
swapping filament, and moves the printbed out of the way.  So make the
default by to home X but not Y.

In both cases we travel fast to nearish the endstop (within 25mm), and
then do the home (which is slower).  This gets us going as quickly as
possible (which is helpful to avoid ooze).

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/plugins/pauseAtZ.py b/plugins/pauseAtZ.py
index a4118a00c677626adc6f8a7fc8227034c27d3bb8..fa9a3aedcb22ee26cfe71a0eaa46b03711e6446e 100644 (file)
--- a/plugins/pauseAtZ.py
+++ b/plugins/pauseAtZ.py
@@ -8,6 +8,8 @@
 #Param: moveZ(float:5) Head move Z (mm)
 #Param: parkMinZ(float:15) Minimum head park Z (mm, abs)
 #Param: retractAmount(float:1) Retraction amount (mm)
+#Param: homeX(bool:true) Re-home X on restart
+#Param: homeY(bool:false) Re-home Y on restart
 
 __copyright__ = "Copyright (C) 2013 David Braam - Released under terms of the AGPLv3 License"
 import re
@@ -109,6 +111,20 @@ with open(filename, "w") as f:
                                f.write("M84 E0\n")
                                #Wait till the user continues printing
                                f.write("M0\n")
+
+                                #Re-home the axes, in case the operator has perhaps jostled the printer
+                                if homeX or homeY:
+                                        g1 = "G1"
+                                        g28 = "G28"
+                                        if homeX:
+                                                if parkX > 25: g1 += " X25"
+                                                g28 += " X"
+                                        if homeY:
+                                                if parkY > 25: g1 += " Y25"
+                                                g28 += ' Y'
+                                        f.write(g1 + " F9000\n")
+                                        f.write(g28 + "\n")
+
                                #Push the filament back, and retract again, the properly primes the nozzle when changing filament.
                                f.write("G1 E%f F6000\n" % (retractAmount))
                                f.write("G1 E-%f F6000\n" % (retractAmount))