Building a chain driven Plasma table.

So I figured it out.
I installed ohmic3 comp.
Put the Hal file into the config folder of my machine and edited the ini file and added the ohmic Hal file.
Linuxcnc starts now without any error messages.

Probe test works.
But if I press ohmic test nothing happens.

  Is there anything I have to change here?

I found some strange thing happening on my table. In Hal show under ohmic voltage I see an erratic change of voltage. 
Between 2 and 25 volts. 

If I touch the torch with the negative cable from the power supply that is supposed to go to the workpiece I get a stable voltage of about 25 volts. If I put the same cable into the water I also get stable 25 volts.

I just found the cause of the strange voltages. 
it was some dirt that accumulated between the torch nozzle and the Shield. 
after cleaning the voltage dropped drastically. Between 2 and 10 volts. 
after this I put a pull up Resistor between positive in and negative in of the Thad.

that put the fluctuation to below 5 volts 
 Now it looks like ohmic probing works perfectly. 

  So I thought I will share a bit about my chain driven machine. I learned it is possible to make a good machine that is chain driven. it has its own advantages and disadvantages. I found after dealing with all the plays of gears on shafts. Dealing with gears that don’t run true. I have a machine with zero backlash. it runs quiet hardly any chain noise except when moving long distances on maximum speeds.  Also the bearings running on a rectangular tube has no issues. Only issue I have is that the X axis flexes a bit when the machine stops suddenly that’s why I reduced the acceleration to 750 mm. The shaking originates from the flexing of the two side plates of the Gantry during hard acceleration. So I will redesign them to make them lighter and more rigid. Hole cutting has improved a lot. But there is still more I can do.

I have added some buttons to the control box.  But it seems Qtplasmac just ignores them. I have configured them with pncconf.
In halshow I can see that the machine reads them. But that’s all if I press the white button that is configured to start a cycle nothing happens. Are there more things that I need to configure so that the button will work?
Is there any tutorial about adding physical buttons?


 

Are the buttons connected to the appropriate QtPlasmaC external HAL pins?

linuxcnc.org/docs/2.9/html/plasma/qtplas...l#plasma:ext-hal-pin
 

So basically pncconfig does not do configurations that are specific to qtplasmac.

Could I move the appropriate lines for these buttons from my Hal file to the postguy halfile. And just replace the pins that pncconfig created with the appropriate Qtplasmac external Hal pins?

Creative25 wrote:

So basically pncconfig does not do configurations that are specific to qtplasmac.

PNCconf has not been taught anything about the external HAL pins.

Could I move the appropriate lines for these buttons from my Hal file to the postguy halfile. And just replace the pins that pncconfig created with the appropriate Qtplasmac external Hal pins?

Yes, that should work fine.

  Is this the way my postgui Hal should look like?