Educate me On THC

While our tables don’t have thc, I would like to upgrade in the future. I’ve been shopping for a machine torch and noticed there’s only 2 pins plus the central connector. Where are the voltages sent from that the thc uses to control the z axis?

I watched some videos on youtube awhile back on setting up torch height control on DIY machines. And you will need to purchase a torch height controller.

This video should help.

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I know I’ll need to get one, the table I’m looking at purchasing in the future has torch height already included, I was just wondering where the arc voltage comes from, within the cutter or does another set of wires need to be ran to the torch itself…

The two pins pretty much tells the machine that there is a cap on the end of the torch and it is ok to fire the torch.

As far as a thc. There are only 4 inputs on the breakout board (bob) which you will need to add in, so choose your thc wisely. Let’s say you did the proma thc 150. You send two signals to the bob, up and down. The proma thc also has arc ok signal which tells mach it’s ok to move. Now you are left with 1 input which I would suggest to use as a probe input for z axis touch off for initial height.

You could use the the proma thc sd which intercepts the signal to the z axis stepper driver and doesn’t send any signals to the bob. I think this would be the way to go with the current bob. Your plasma machine may have the option to send an arc ok signal directly to bob and now you have 3 inputs left for other things, z axis probe, e-stop, limit switch, etc.

Also you will need to modify your bob and mach to accept inputs, which I describe here

Just my two cents.

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Thanks guys, been looking at a powered z axis, and at the same time want to increase my cutting size.

Seemed to make more sense to just buy another table if I’m going those routes.

I’m not looking to mod the crossfire, when I upgrade, I’m looking at a cutting edge plasma 4x4, has integrated thc, I was just looking to see how it functioned

Please don’t get me wrong though. I do love my crossfire very very much