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View Full Version : Need Help! Pierce Delay even when set to 0?



Wolfesmetalfab
01-30-2009, 01:48 AM
I am having a pierce delay (plasma), even when set to 0. Not long, but it makes an unecessarily large pierce hole when it doesn't need to delay.

Any ideas? I thought maybe it was the spindle incr. setting in general config waiting for it to spin up, it was set at 10, and spindle speed in gcode is 500, so i tried setting it to 500, and didn't seem to make a difference???

I would like to get rid of this if possible. Also if you see something else wrong in the post or gcode, let me know, Im learning well, but still a long ways to go. :)

here is a gcode for a straight line test cut using sheetcam, I cant find anything weird, so I think its with mach.

I am setting z home switch offset in the post file, and using sheetcam for pierce delays, heights, etc.

------------------

N0000 (Filename: 2&half horizontal line.tap)
N0010 (Post processor: Brians Plasma THC300.scpost)
N0020 (Date: 1/30/2009)
N0030 G20 (Units: Inches)
N0040 G53 G90 G40
N0050 F1
N0060 S500
N0070 (Part: 2&half horizontal line)
N0080 (Process: nil)
N0090 M06 T3 (1/4" steel 60 amp)
N0100 G00 Z1.0000
N0110 X0.0000 Y0.0000
N0120 G28.1 Z0.12
N0130 G92 Z0.0
N0140 G00 Z0.3575
N0150 G92 Z0.0
N0160 G00 Z0.1250
N0170 M03
N0180 G01 X0.0000 Y0.0000 Z0.0625 F100
N0190 X2.5000 F40
N0200 M05
N0210 G00 Z1.0000
N0220 X0.0000 Y-0.2500
N0230 M05 M30

----------------------

Here is my post file

function OnAbout(event)
ctrl = event:GetTextCtrl()
ctrl:AppendText("plasma THC300 post processor\n")
ctrl:AppendText("\n")
ctrl:AppendText("Modal G-codes and coordinates\n")
ctrl:AppendText("Comments enclosed with ( and )\n")
ctrl:AppendText("M03/M05 turn the torch on/off\n")
ctrl:AppendText("Incremental IJ\n")
ctrl:AppendText("The torch is referenced at cut start and every 500mm of movement thereafter\n")
ctrl:AppendText("Designed for use with Mach2 and Campbell Designs THC300\n")
ctrl:AppendText("Post variables:\n")
ctrl:AppendText("refdistance - set the distance between each reference\n")
end



-- revision 3/2/07
-- Removed final safety move. This is now done in SheetCam

-- revision 7/10/05
-- Added new arc handling

-- created 27/10/04
-- Based on plasma1.post



function OnInit()

post.SetCommentChars ("()", "[]") --make sure ( and ) characters do not appear in system text
post.Text (" (Filename: ", fileName, ")\n")
post.Text (" (Post processor: ", postName, ")\n")
post.Text (" (Date: ", date, ")\n")
if(scale == metric) then
post.Text (" G21 (Units: Metric)\n") --metric mode
else
post.Text (" G20 (Units: Inches)\n") --inch mode
end
post.Text (" G53 G90 G40\n F1\n S500\n")

dist = 9999999
refdistance = 500 * scale
switchoffset = .3575
bigArcs = 1 --stitch arc segments together
minArcSize = 0.05 --arcs smaller than this are converted to moves
end

function OnNewLine()
post.Text ("N")
post.Number (lineNumber, "0000")
lineNumber = lineNumber + 10
end


function OnFinish()
post.Text (" M05 M30\n")
end

function OnRapid()
if(endZ < currentZ) then return end
dist = dist + math.hypot(endX-currentX , endY-currentY)
post.ModalText (" G00")
post.ModalNumber (" X", endX * scale, "0.0000")
post.ModalNumber (" Y", endY * scale, "0.0000")
post.ModalNumber (" Z", endZ * scale, "0.0000")
post.Eol()
end

function OnMove()
dist = dist + math.hypot(endX-currentX , endY-currentY)
post.ModalText (" G01")
post.ModalNumber (" X", endX * scale, "0.0000")
post.ModalNumber (" Y", endY * scale, "0.0000")
post.ModalNumber (" Z", endZ * scale, "0.0000")
post.ModalNumber (" F", feedRate * scale, "0.###")
post.Eol()
end

function OnArc()
dist = dist + math.hypot(endX-currentX , endY-currentY)
if(arcAngle <0) then
post.ModalText (" G03")
else
post.ModalText (" G02")
end
post.NonModalNumber (" X", endX * scale, "0.0000")
post.NonModalNumber (" Y", endY * scale, "0.0000")
post.ModalNumber (" Z", endZ * scale, "0.0000")
post.Text (" I")
post.Number ((arcCentreX - currentX) * scale, "0.0000")
post.Text (" J")
post.Number ((arcCentreY - currentY) * scale, "0.0000")
post.ModalNumber (" F", feedRate * scale, "0.0###")
post.Eol()
end


function OnPenDown()
if(dist >= (refdistance/scale)) then
dist = 0
post.ModalText(" G28.1 Z")
post.Number(3 * scale, "0.00")
post.Eol()
post.ModalText(" G92 Z0.0\n")
post.ModalText (" G00")
post.ModalNumber(" Z", switchoffset, "0.0000")
post.Eol()
post.ModalText(" G92 Z0.0\n")
post.CancelModalNumbers()
end
post.ModalText (" G00")
post.ModalNumber (" Z", pierceHeight * scale, "0.0000")
post.Eol()
if (preheat > 0) then
post.Text ("\n G04 P")
post.Number (preheat,"0.###")
post.Eol()
end
post.Text ("\n M03\n")
if (pierceDelay > 0) then
post.Text (" G04 P")
post.Number (pierceDelay,"0.###")
post.Eol()
end
end


function OnPenUp()
post.Text (" M05\n")
if (endDelay > 0) then
post.Text (" G04 P")
post.Number (endDelay,"0.###")
post.Eol()
end
end


function OnNewOperation()
post.Text (" (Process: ", processname, ")\n")
if (plungeRate <= 0) then
post.Warning("WARNING: Plunge rate is zero")
end
if (feedRate <= 0) then
post.Warning("WARNING: Feed rate is zero")
end
end

function OnComment()
post.Text(" (",commentText,")\n")
end

function OnToolChange()
post.Text (" M06 T")
post.Number (tool, "0")
post.Text (" (", toolName, ")\n")
end

function OnNewPart()
post.Text(" (Part: ",partName,")\n");
end

function OnDrill()
OnRapid()
OnPenDown()
endZ = drillZ
OnMove()
OnPenUp()
endZ = safeZ
OnRapid()
end

---------------------------

???

Brian

thedoctor
01-30-2009, 12:25 PM
Looks to me like the process is waiting for the Z axis to make a short move. How fast is your Z motion? I assume you don't use any "prove-arc" command from the plasma power source as a motion interrupt.

Wolfesmetalfab
01-30-2009, 01:19 PM
I have pierce set at .125, and cut at .0625, so it has to move .0625, Velocity is 100 ipm, and accel is 15, so theoretically (if my math is correct) it should take approx .037 of a second, and the delay is much longer than that, its more like 1-2 seconds.

I do not have a prove arc command right now, but the hypertherm does have the easily accessible xfer (machine move) feature available, which in another thread, I am seeing if anyone knows how to use this without a THC. (I have the soundlogic board and use mach)

Wolfesmetalfab
02-02-2009, 11:00 PM
Ah HA! I found it on my own! Im posting, cause maybe someone else will have the same problem.

In the ports and pins settings, Spindle setup Tab, the options that deal with CW and CCW spin up and spin down were set at 1 instead of 0! Now that I changed it, It does what I want.

Now, I have to go back and reset the pierce delay for my tools to cut heavier metals, the right way, not starting with 1 sec of delay! :)