Those are nice, but expensive if you use the 3 that have been suggested. In my case, my Z axis mechanically floats and breaks a switch contact so the G31 probe code works well IFF you have a repeatable ‘backlash’ on the switch, ie, you can measure the distance from open to re-close and it’s repeatable within a couple of mil. The downside of using my method is that the weight of the ‘floating’ gantry does push the material down and will distort the Z calibration (at least, temporarily), whereas the inductive sensors don’t deflect warped material. Unfortunately, this requires three sensors that can reliably detect the distance to ANY metal (Steel, SS, Al, Copper, Brass, 24Kt gold, etc) that you’re likely to cut and those are expensive…
Price was good so I bought it! 
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Tough to beat that! Looks like the start of Zomething big!
Ok, this is the configuration I’m looking at ultimately (see pic, Thanks Tool Junkie), along with the XL Kit. So buying the necessary stuff as I go along. and building stuff in the shop in my spare time. Right now I’m printing my own stack-light design (designed on SolidWorks), the clear lenses are on the printer now (pic below).
Couple of questions:
- Where does one buy that “Red Board”?
- Do I wanna go Proma or THC3T what’s the pros and cons? (besides cost)
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Ahhh! …thought the Plasma Gods were demanding more money again!
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As far as Proma vs THC3T, I haven’t used the Proma but have looked at the manual and I am very glad I picked the THC3T. There are more tuning controls on the THC3T (Z sensitivity - essentially loop gain, and Speed) and I think you might have more options about Torch input voltage, but I’m not sure about that.
Sounds like a plan!
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May wanna invest in a board , just in case I let the magic smoke out …hahahaha!
It’s virtually the same electronics (different connectors), but the SW MAY be different. Don’t know since Langmuir has a differently named DLL plugin for Mach3. The DLL, however, appears to be identical to the DLL used for the Mach3 USB Controller board (https://buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach3-USB-Board) so…
The linear bearing is not needed at all, any worries about sag are negated by the THC itself.
Proma vs Robot… basically the same, proma is smaller, but i gutted mine and relocated the boards inside. There is a tiny ribbon cable from the main board to the display, i bought a 15" long one for about $6 on eBay.
Both methods of proving have their pros and cons, as someone me tiined the floating z pushes the metal down, so I just push it down with my finger as it’s probing and hold it while it starts cutting then let up slowly, thc handles the rest.
Prox sensors sometimes miss the sensing if you have already had cutouts around where its sensing.
You may have to experiment with different metals and find out how the sensors work with each one i.e. steel might be your zero, then stainless mighy detect higher or lower, so knowing that offset is easy and programmable.
Thanks Dicky, good information. The wait for this thing to get here is killing me. Lol
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The big crate is on the island. Next week I should have it in-hand and begin assembly. Quite a bit of stuff already ordered for implementing the Z-axis and THC, albeit this will be undertaken a bit down the road.
Still a little confused about the THC3T as this is the THC i’ve decided on, but do I need the SD or UP/Down?
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Step/Dir ection
Ahhh, OK, so this is completely independent of Mach3. … Got it!
It IS related to the fact that the CF Control board (AKA USB Mach 3 Motion Control) only produces Step/Dir signals. So the THC has to match that.
Fortunately, the Thc you have selected works for both modes, step/dir and Up/down, its just how you wire it on the version 3 model. The version 4 model I believe has a dipnswitch or setting to let you choose…
I found that as long as you use Factor 1 sensors the metal type does not matter and no adjustment is necessary between ferrous or non-ferrous. I’m using three Automation Direct KSK6-AP-4H sensors, and the array has little difficulty with either metal type or voids as long as at least one has metal under it.
This same board can be found on EBay for $15.
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