Centroid Community CNC Support Forum

Hey there, I would love your help in this non plasma thc issue I'm having.
I'm trying to upgrade my cnc plasma table to a fiber laser one.

I want to use the same acorn plasma thc controller board.
The only thing that I wasn't able to figure out completely is the height control.
Fiber laser machines don't use an arc voltage measurement for height adjusting, they use a capacitance sensor and an amplifier.
The capacitance sensor is sending a signal to the amplifier and the amplifier translate this signal to a 0-10VDC analog signal.
So I figure that I can connect it to the tx board and the result with be the same as an arc voltage measure.
I did it and it works , but for some reason the thc is able to follow the work piece only is the UP direction, in the DOWN direction its not following the work piece, its just stays is the same height and the Z axis is not moving.
In cnc12 it shows clearly that the voltage reading is correct and when the work piece is getting further the voltage increases but for some reason the z axis is not moving down.
Please help me solve this.
I attached videos bellow showing the issue.

Wow interesting concept. Check out the THC config menu and adjust the THC settings to enable the THC to react at any voltage at any speed. Turn on your plot in the F7 utility menu. So you can look back at the plots and see how the THC is reacting to the voltage. Then adjust your THC config settings to stop anti dive setting from getting in your way.

Post a report so I can check out your plots

this is the report.

i dont know what is "plots" or where i turn it on.

Plot is a data capture of the THC. The plot is created at a M62 torch off macro or an interruption to the job. In the THC config menu of the profile manager, set the velocity anti-dive to 1 percent and the anti-dive threshold to 99. This will allow the THC to react to a wider range of speeds and voltages

Hey, so I did as you suggested and its better now.
I also did a new thc calibration.
Its still not as steady as I like it to be.
Which parameters do I need to change to make it more stable and not to go up and down soo rapidly?

In the THC Config menu of the profile manager Try turning the THC feed rate down to a low number. say 20-50ipm? Or clean up the voltage going into the TX board. The Voltage I saw in your plot looked kind of thick. not a thin of a line as I'd like to see. When I looked at your plots the voltage wasn't very clean.

Make sure your plot capture is turned on in the utility menu. Also put an m62 in the gcode at the end of the Lazer cut so that the plot captures the voltage that was read in the cut.
Should be able to get more plots from those runs in your video and I can better help adjust your thc. The plots have all the information that the thc is reacting with in the job. Do you have internet at the tables PC? id like to help show you how to read the plot and tune the THC. Your getting close

I don't know where Is the option in the utility manu to turn on the plot.
I do have an Internet in the computer that the acorn board is connected to.
I'm not sure i understand the meaning of "clean voltage", i would appreciate your help in understanding it.

What version of software do you have? Make sure you have V4.82 installed.

In the F7(utility) menu there is an option to open the plot and an option to turn plot capture on and off.

Do you have Whatsapp? What time zone are you in?

You can contact me on Whatsapp to set up a TeamViewer session.
Whatsapp link https://call.whatsapp.com/video/qcTLCqW9JqokgQS5uqpUcx

Have you found the plot yet? You can take the long route and open the plot.exe from the cncm folder