Hi Dicky. It looks like you did a really nice job. I may attempt this one day. I am wondering about something though. Is your THC adjusting during the cut to maintain the proper torch height ? I seem to remember another home made system posted here that did not adjust ? Just wondering.
Thanks for posting all of this.
It is adjusting during the cutting. It is also setting zero at each pierce point based off the material height. For this part it’s good, some other things its not.
Awesome! Looks like you got everything worked out!
It’s been a while since I have used mine but is it cutting in the wrong direction? @jamesdhatch what do you think?
Cutting in the wrong direction??? Looks good to me, top to bottom! LOL
If you mean the THC cutting backwards, it’s not. Clockwise is raising the Z, and the plate is high in the middle, by like 3/8". So all is good! Unless there is something else I don’t know about???
I do have an issue, probably something in the setup I can’t find. I have popped the breaker in my panel a couple of times (it’s being fixed) but what I noticed is that while the machine and plasma stop completely, Mach 3 keeps running like the machine is still running. I though once it lost the arc ok signal mach would stop executing the code… Something I’m missing?
Not the z axis. The actual cut profile. Again, I haven’t used mine in a while but I’m thinking the cut profile is backwards. I think it’s supposed to be inside circle cut CCW while outside profiles cut CW. Does the edges have a severe bevel?
Is the arc ok signal from the plasma machine going to the thc or is it going to the bob?
Or does the thc have an output for arc ok?
I didn’t know the direction mattered. Arc ok comes from the thc to the bob, it does register in mach 3 inputs
Hi Dicky, The torch ok comes from the plasma cutter, but in this case it doesn’t matter because you are using a USB BOB and Mach3 can’t see it . Mach 3 doesn’t know you have a THC either, your THC is running stand alone. you could remove the wires for ARC ok, torch up and torch down and your machine would still function as it does right now. you would only lose the LED indicators on the troubleshooting
screen. This is what I told you about before, it’s ok you can still make it work in stand alone but you will be limited to the features of your THC, this is why they made THC’s with direct control. (your Step in out, DIR in out on the THC) yours has both direct control and Mach3 control (if you had a different Bob)
I was watching your video of it cutting and it didn’t look like you had a Pierce height set, are you using it? you normally set it for 2x your cut height, sure saves consumables.
If you are having stability problems with Mach3 you may want to use version 62 if you are not already
66 has issues. anyway my 2 cents, hope this helped. ToolJunkie…
So I did my full(ish) writeup. Hope it helps someone else on their journey! Thanks to all those who helped me along the way! If I think of more, I’ll update the doc…
https://drive.google.com/drive/folders/1UiEoivKU4MeXWc9-Z9zcQE4C01WLjXGu?usp=sharing
Nice write-up. I may follow your lead on this if I can find some spare time 
Very nice and detailed , And looks great, Thank you for sharing .
Very nice, thanks for sharing.
Thank you for all the informations! I started to do it for my plasma table too!
Looking good! Is that the proma 150 SD? You’ll have to wire it between your z axis driver and the break out board. I like that case! I almost bought one of the pelican knock offs from harbor freight to do the same thing. I ended up with a metal one from amazon. Haven’t gotten into that yet!
Yes, this is theProma SD, i wired it today! I have a question for you… did you change the jumpers position on the relay module? Mine came without any instructions…
The case i bought measure 17" X 14" X 6" and is a little too small. I didn’t finish the wiring yet, and i don’t know where is will install the cooling fan…
I didn’t use the proma, but @ToolJunkie would be your best bet, he has that one up and running
I just ordered my crossfire system and was browsing, I think your THC solution is brilliant. Could you share more details/parts for the floating switch head portion? I’m guessing two little rails but I’ve been hunting amazon/ebay but I haven’t seen any rails as slim as yours. In practice, do you end up using yor full travel area? I’m wondering if I can’t get away with 50mm travel vs your full 100mm.
Thanks!
That unit was left over from another project… Those are made by THK, very expensive! I think you can find them on ebay. There is a 3d printed version that I would have went with had I not had this laying around. I’ll see if I can find the link… Actually I may like this better to be honest, it seems a little more stout.
Here is the manufacturer site, these would do…
https://www.thk.com/?q=in/node/3036
or these, similar to what I am using.
https://www.nbcorporation.com/shop/slide-way-gonio-way/miniature-ball-slide-sybs/
