thc touch off and switch travel

[elgonzo]

Hello all,


I am running mach3 on a 3 axis plasma table using a floating head switch on the z-axis. For the mach display i am using the THC-300 screen set that is offered by cambell designs.

For a test file I drew a simple square and generated the g-code using sheet cam with the THC-300 Post processor




Can someone with this similar setup help me clarify a few questions.


1. When I change any of the values in the "settings" tab, there is no effect i.e no cut height change, no Peirce height change. DO these fields work HuhHuhHuhHuh

2. Do people set properties such as Peirce height , Peirce delay , and cut height thought sheet cam or do u use the "settings" tab



thanks for any help in advance !!!!!

[Torchhead]

If you are using SheetCAM then the settings need to be put in the Tool Chart parameters. The SwitchOffset variable in the POST should be edited and changed to your actual switch overtravel value on the floating head. You can't use the MACH macro's and settings in SheetCAM. I have no idea why Campbell Designs still has the elements on the screens or the macros. You don't need pierce delay if you use the Arc Good sensor and the THC logic in MACH. It automatically holds motion until an arc is established.

TOM CAUDLE
www.CandCNC.com

[richyrich212t]

Tom,

Is this were the switch offset is edited in the POST file ???


function init()

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

dist = 9999999
refdistance = 500 * scale
switchoffset = 0
bigarcs = 1 --stitch arc segments together
minarcsize = 0.05 --arcs smaller than this are converted to moves

[Torchhead]

yep! Switchoffset = [your switch offset value in decimal inches]

To find the value:

1. Perform a REF form MACH screen on Z. It will move down and stop
2. Reset Z DRO in MACH to 0
3. Jog Z up until you can slips a piece of paper between the tip and the metal
4. Read the Z DRO. That is your net switch offset

TOM Caudle
www.CandCNC.com