CommandCNC THC voltage setting

[Ironken]

I'm helping a buddy out with CommandCNC, I don't have CommandCNC (I have a JD2) and would like some guidance on changing THC voltage settings.

Reason being is we would like to do some straight line cuts to tune in some angularity issues with feed changes. The way I do it on my machine is disable the THC, make some straight line cuts with different feeds, observe the actual voltage and apply this data and use as a new tool.....presto, better cut.

Can anybody help me apply this to commandcnc if I even made sense. Bottom line is in command cnc, I don't know where to change the voltage setting to info from the straight line cut test or simply to adjust the THC cut height by changing voltage.

Thanks to anybody willing to help.

[WyoGreen]

If he's using CommandCNC, then he's using Sheetcam to produce his G-code. The voltages, cut speeds, etc. are done in the tool table in Sheetcam.
The straight line test cuts are done the same way you've been doing them.
Steve

[Ironken]

If he's using CommandCNC, then he's using Sheetcam to produce his G-code. The voltages, cut speeds, etc. are done in the tool table in Sheetcam.
The straight line test cuts are done the same way you've been doing them.
Steve

Thank you for the help, Steve! We'll give it a go. I did not think to do it in sheetcam as my JD2 cnc program allows for those adjustments to be made on the machine after the post.

[robertspark]

Yes, sheetcam has the settings for these and these are sent via gcode

However the bit that's missing from this thread of posts is that sheetcam needs the right post processor in order for these values and settings to be shown within sheetcam and also to allow sheetcam when carrying out the post processing operation to correctly insert the right gcode into the *.tap, *.nc etc file when carrying out the post processing operation.

You can download the latest postprocessors from candcnc's website here:

https://www.candcnc.net/downloads/

It will add all of the cells to the tool settings etc.

Sheetcam does not have those values by default.... They are added because of code in the post processor.

Also there is a toolset on the candcnc website which adds all of the default tool cutting parameters (hypertherm powermax 45-105 "book values"), and these populate the cells added by the post processor.... Otherwise you will have to create the tools and populate the cells for every material and material thickness you wish to cut.

I am not a candcnc /commandcnc user

[Ironken]

That makes sense, Robert. He has the post processor loaded from LDR and has been cutting for some time. He is to the point where he would like to fine tune some cuts on thicker material and did not know where to change the voltage values for THC. Thank you for taking the time to help....I appreciate it!

[dhelfter]

On the computer we supplied, is a folder named manuals, located in the documents folder, and a link on the desktop. In the operating and setup section is a file name DTHC basics
That file explains step by step how to do what you would like.

Thanks
Dan
LDR

[dhelfter]

Also the post processor installed is the correct one, and each tool will have the appropriate are to enter your desired voltage and such.
You do not need to change the post processor installed.
Thanks
Dan

[Ironken]

Thank you, Dan! Top notch service. Since I have you here, do you offer an upgrade kit to break away torch and ohmic for this LDR 4x4? Do you recommend upgrading to the new Commandcnc released program?

[dhelfter]

I do recommend upgrading. Lots of new features.
Ohmic sensing can be added from us or directly from candcnc.
Sorry no we do not use a magnetic breakaway.
I am not on forums a lot, so if you need any assistance best method is direct email from our website.
Thanks
Dan

[Ironken]

Good info. Thank you again, Dan!

[motoguy]

Same process you're used to.

Confirm correct torch height (stop torch right after the cut, use feeler gauges/coins/scrap material to measure cut height, etc).

Once you confirm the torch is at the correct cut height, cut an 8-10" straight line, with THC turned off. Watch the voltage reading on the screen, and try to get an "average" reading. For flat material, on flat slats, it should stabilize after the first couple inches of cut, and stay stable until the last inch or two.

That "average" voltage is your target voltage 1) for that cut height 2) at that cut speed 3) on that material 4) using those consumables and air pressures

Plop that number back in as your programmed/g-code/tool-set number, and see how it works. Fine tune from there.

[motoguy]

That makes sense, Robert. He has the post processor loaded from LDR and has been cutting for some time. He is to the point where he would like to fine tune some cuts on thicker material and did not know where to change the voltage values for THC. Thank you for taking the time to help....I appreciate it!

He can change the THC voltage values in the tool chart, in Sheetcam. He can also change them "on the fly" on the CommandCNC screen, where the voltage is displayed.

[motoguy]

Also, I recommend comparing the supplied CandCNC settings to the actual book settings. The files supplied with my machine (back in 2015) were not correct book settings. Took me some crashes to realize this.

[Ironken]

Motoguy, thank you for the detailed instruction! I have passed on all of the info to my buddy. He is going to do as you guys have advised tonight. I'll post back with what he comes up with. Thanks again to all that took the time to help out!

[tara]

thank you for the nitty gritty guidance! I have passed on the majority of the information to my amigo. He will do as you all have exhorted this evening. I'll post back with what he thinks of. Because of all that set aside the effort to assist!