Help with thcad

is the value of velocity tolerance a percentage of the total velocity from the machine? I mean
total velocity 100%
velocity tolerance 20%

thank.

There have been some different versions of the THC, however on yours I believe it is the velocity tolerance.
That is if you set your speed at 200 and you set the velocity tolerance at 20 then
200 * .20 = 40
200 - 40 = 160
So the machine needs to be moving at least 160 for the THC to work.

Rick G

Ok I understand, tomorrow I will do some test with these values and then I will tell you how it was.
Thanks.

Hello I've made some test today and I noticed that thc.status-vel never is true when machine is cutting. can it be a bug of the thc component. where can I see the source code of thc.comp i have installed in my computer?
I could prove that from this internet thc code I should get a thc.status-vel set to 1 but get always 0.

if(enable){
float min_velocity = requested_vel -(requested_vel*(1/velocity_tol));
if(current_vel > 0 && current_vel >= min_velocity){vel_status = 1;}
else {vel_status =0;}

Can I see the thc source code of thc comp I have installed in my computer? how can I know what is the version i am using ?
as all condition to correction seem to be ok but z axis doesn't move.

ARC-OK true
TORCH-ON true
THC enable true
vel-status true

I don't know why but i have to set the following in .hal file to get vel-status working

setp thc.velocity-tol 40

here you have a pic to see all values while machine is cutting.

github.com/LinuxCNC/linuxcnc/blob/master.../components/thc.comp
linuxcnc.org/docs/2.7/html/man/man9/thc.9.html

That seems to show a thc.requested-vel of 33.3333
But a thc.current-vel of 25

Are you using the feed override slider to change the speed?
If so be sure to set it at 100%. Setting it too low will cause the THC to not work.


Rick G