Trying to help via yahoo messages did not get through am I wrong?

Sorry for the title there let me explain a bit better, there was a message posted a few days ago on the Yahoo group about using Sheetcam, Mach3 and a THC.

Here was the persons message:

Hello friends
i have a cnc plasma working with mach3 and sheet cam TNG development under winxp
the control of Z by THC proma
"With which post process sheetcam should I work?

"I want to work with the auto zero how to changed the post processor sheet cam to make this?
I already have a Macro on Mach3 M800 for auto Zero

best regard


Now I thought that these messages still got through, the M800 macro he referred to above was a copy of one I use, but I thought that for him the could have been a better way using one of the provided posts in Sheetcam. My reply was as follows:

Hi Elkhomri I tried to get to you via Youtube, I am going to stick my neck out here and suggest you try the post processor Mach3 plasma THC with scriber.scpost

Remove the M800 macro you have stuck in there and for the time being try the above post

You have to edit the post to switch off scriber and to set other parameters.

Consider changing these

These are my thoughts

Write a few macros to switch on and off THC such as
M101.m1s is EndTHC()
M102.m1s is StartTHC()

If I knew more about it before I did my machine I would have tried this out.
I think these may work but I hope someone may be around later to correct.

So if no scribe

–*** Set these values up to suit your machine ***

–this is the distance between each torch reference in MILLIMETRES
refDistance = 250

–this is the reference feed rate in mm/min
refFeed = 500

–Put your switch offset value here in MILLIMETRES
–Put a sheet of metal on your machine and place a sheet of paper on top.
–Slowly jog the torch down onto the paper until the touch-off switch just operates.
–Zero the Z axis then pull gently on the paper and slowly jog up until the paper slides out.
–The Z axis position is your switch offset.
switchOffset = 1.5

–Scriber X,Y,Z offsets in MILLIMETRES. Do not use inches here even if you want inch code
–Use the special code ‘nil’ on the Z axis to disable it.
–In that case no Z values will be output at all while scribing.
–e.g scriberZ = nil
scriberX = 110
scriberY = 220
scriberZ = nil

–scriber axis. Leave this as nil if the scriber is fixed to the same axis as the torch
–scriberAxis = “A”
scriberAxis = nil

–The cutter will slow down for corners and turn off THC below this radius
slowRadius = 10

–Minimum slow down speed.
–This is a scale factor. For instance 0.5 = 50% of the current feed rate
slowPercent = 0.4

–THC on and off codes. Use nil if you don’t want THC control e.g:
– thcOnCode = nil
– thcOffCode = nil

–here is another example that use M667 and M666
–thcOnCode = " M667"
–thcOffCode = " M666"

thcOnCode = M102
thcOffCode = M101

–Use the home switch (G28.1)
–Set to false if you use the probe input (G31)

–*** End of settings ***

I am really not sure how the post works with the anti dive on Mach3, or if some of the above bits are required if you use cut rules to control speed so I really do hope someone else will tell me where I am right or wrong on these. Make sure you do not use things like M8 or M9 for turning on the electronics as the post uses M8/M9 on the scribe.

Best of luck.


So I sent that back via yahoo in the hope that someone with more knowledge would jump in, I think it never got through. Please let me know if any of the above was correct or wrong and if there is a better post to use?

Many thanks