Toolpath wants to start at Z 0

Topics related to wrapped rotary machining in Aspire or VCarve Pro
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skulls
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Toolpath wants to start at Z 0

Post by skulls »

I have my file(s) set up with Z at the center point of the stock, and if I go to material setup under "Home / Start Position" for Z Gap above Material it's 8mm. The diameter is set correctly and I'm using a cylinder for stock. But when I export the toolpath and import it into either universal gcode sender platform or basic sender, the simulation in that program shows the bit start at 0,0,0 before moving up to a path above the stock. If I ran that, it would first try to drill down to the center of my wood, much tears, death, etc.

How can I prevent the toolpath returning to Z 0?

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adze_cnc
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Re: Toolpath wants to start at Z 0

Post by adze_cnc »

If that's something you can't over ride in your controller software I expect that in your post-processor there is a line to do a return home in the "begin FOOTER" block (it could look like this):

Code: Select all

"[N]G00[XH][YH]"
The fix would then be to remove the "[ZH]" at the least

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SteveNelson46
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Re: Toolpath wants to start at Z 0

Post by SteveNelson46 »

Are you using the correct pp for wrapped rotary?
Steve

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adze_cnc
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Re: Toolpath wants to start at Z 0

Post by adze_cnc »

Oops. My brain totally skipped the cylinder sentence.

skulls
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Re: Toolpath wants to start at Z 0

Post by skulls »

I'm using the post processor that was recommended by the manufacturer. Called XZAR 1.1.

Here's the footer part -

Code: Select all

begin FOOTER

"M5"
"G0[ZH]"
"G0[XH][YH]"
"M2"
Edit: I'm going to try removing the line G0[ZH] as soon as I can get back to my cnc.


Actually, here's the whole file, in case it's relevant -

Code: Select all

POST_NAME = "XZAR (mm) (*.gcode)"

FILE_EXTENSION = "gcode"

 
UNITS = "MM"

ROTARY_WRAP_Y = "A"


+------------------------------------------------
+    Line terminating characters                 
+------------------------------------------------
 
LINE_ENDING = "[13][10]"
 
+------------------------------------------------
+    Block numbering                             
+------------------------------------------------
 
LINE_NUMBER_START     = 0
LINE_NUMBER_INCREMENT = 10
LINE_NUMBER_MAXIMUM = 999999
 
+================================================
+                                                
+    Formatting for variables                     
+                                                
+================================================
VAR WRAP_DIAMETER = [WRAP_DIA|A||1.4]
VAR LINE_NUMBER = [N|A|N|1.0]
VAR POWER = [P|C|S|1.0|10.0]
VAR SPINDLE_SPEED = [S|A|S|1.0]
VAR FEED_RATE = [F|C|F|1.1]
VAR X_POSITION = [X|C|X|1.4]
VAR Y_POSITION = [Y|C|Y|1.4]
VAR Z_POSITION = [Z|C|Z|1.4]
VAR X_HOME_POSITION = [XH|A|X|1.4]
VAR Y_HOME_POSITION = [YH|A|Y|1.4]
VAR Z_HOME_POSITION = [ZH|A|Z|1.4]
 
+================================================
+                                                
+    Block definitions for toolpath output       
+                                                
+================================================
 
+---------------------------------------------------
+  Commands output at the start of the file
+---------------------------------------------------
 
begin HEADER
"T1"
"G21"
"G90"
"G0[XH][YH]"
"G0[ZH]"
 
+---------------------------------------------------
+  Command output after the header to switch spindle on
+---------------------------------------------------
 
begin SPINDLE_ON

"[S]M3"


+---------------------------------------------------
+  Commands output for rapid moves 
+---------------------------------------------------
 
begin RAPID_MOVE
 
"G0[X][Y][Z]"


+---------------------------------------------------
+  Commands output for the plunge move
+---------------------------------------------------

begin PLUNGE_MOVE

"G1[X][Y][Z][F]"

 
+---------------------------------------------------
+  Commands output for the first feed rate move
+---------------------------------------------------
 
begin FIRST_FEED_MOVE
 
"G1[X][Y][Z][P][F]"
 
 
+---------------------------------------------------
+  Commands output for feed rate moves
+---------------------------------------------------
 
begin FEED_MOVE
 
"G1[X][Y][Z][P]"
 
 
+---------------------------------------------------
+  Commands output for the first clockwise arc move
+---------------------------------------------------
 

+---------------------------------------------------
+  Commands output when the jet is turned on
+---------------------------------------------------

begin JET_TOOL_ON

"M4[P]"

+---------------------------------------------------
+  Commands output when the jet is turned off
+---------------------------------------------------

begin JET_TOOL_OFF

"M5"

+---------------------------------------------------
+  Commands output when the jet power is changed
+---------------------------------------------------

begin JET_TOOL_POWER
"[P]"


 
+---------------------------------------------------
+  Commands output at the end of the file
+---------------------------------------------------
 
begin FOOTER

"M5"
"G0[ZH]"
"G0[XH][YH]"
"M2"

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adze_cnc
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Re: Toolpath wants to start at Z 0

Post by adze_cnc »

Note that a reference ZH is also in the "begin HEADER" section (that is at the beginning of the cut).

skulls
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Re: Toolpath wants to start at Z 0

Post by skulls »

Thank you for pointing it out. I'll try removing that one too.

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Re: Toolpath wants to start at Z 0

Post by skulls »

Amusingly, that made the open toolpath look different, but the new one is also starting at Z0. It used to start at Z0 and move directly up to above wood, and now it starts at Z0 but has more of a slope moving toward the center of the wood to start. I'm going to try asking about the sender software and see if it's a setting in there, too.

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