Another newb another THC question.

[Boh347]

Pretty sure you guys are sick of hearing the same old questions, but I've googled until my eyes are crossed. I recently purchased a used burntables and can't seem to get the torch height control to stop. it continues into the metal until I click stop. I'm assuming it's not reading the volts.

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[jimcolt]

Why not contact Burntables?

Jim Colt

[shiner2001]

Good luck. If you can return it to whoever you bought it from, I would do that immediately. Their THC is pure junk.

[motoguy]

I hate to be the bearer of bad news...but you're not going to find much good news about it. As you already own it, there's no reason to beat you up further. In all seriousness, you may as well start looking into an electronics refit if you want to get some use out of it. Tom at CandCNC did a Youtube video about retrofitting a Burntables unit with his controls. You may want to contact him about that option.

[WhitesPerformanceMachine]

Not sure how you made out with this, but I'm in the middle of figuring out how to scrap the Burntables THC and replace it with the Proma THC. I ALMOST have it working.

[tcaudle]

The Promo is a slight step above the "knob twister" THC the BT uses. It should perform okay with the hardware you have . The top speed of the Z is about 37 IPM (has a 3/8 -16 all thread "leadscrew") so you have to spin the devil out of the Z motor to get any feedrate.

The Promo uses mechanical relays on the UP and DOWN signals so it adds delay time to the THC loop so quick changes are out of the question. Since the BT won't cut very fast anyway (poor acceleration and lose linear slides ) you should at least be able to do some cuts on thicker material. You will find the voltage settings while cutting at reduced speeds to be off and you will have to raise the Preset Volts. Best thing to do is calibrate it while running with the THC turned off and watch the volts as it cuts.

[WhitesPerformanceMachine]

I figured it as an upgrade from a non-working THC, to me the machine did okay for what it is. I certainly could have spent my money more wisely but I didn't know any better at the time. If I saw a big potential to make a ton of money then I would sell this and buy a new one, but its basically a hobby and I sue it for artsy firepits and some one off fab work. What I really want is a good CNC Mill and CNC Lathe and actually make some nice parts. HAHA

[tnjind]

I have a burntable I bought REAL cheap. I gutted the box to make it work and gave close attention to the rails and bearings. It is functioning OK. I too am in the middle of retroing a Proma. So far not much luck, it stops the table for no apparent reason. I hope you post your progress.

[WhitesPerformanceMachine]

tnjind, I have everything figured out EXCEPT my Hypertherm isn't sending the voltage to the Proma. I had one copy of the burntables Mach3 setup that triggers the e-stop randomly, I do have a profile that I went through very thoroughly and I'm cutting parts again no problem. Once I get the voltage issue straightened out with the Hypertherm I should have working THC again.

[acourtjester]

With the Proma you may need to go with the raw voltage and not the voltage divider.
When I used a Proma on both a Longevity and Hypertherm Plasma units that is how I had them hooked up.
The DTHC-IV from CandCNC is much better I am happy with the change to that system.

[WhitesPerformanceMachine]

I'm actually in the process of troubleshooting my Hypertherm PM65 now. It is only outputting .25V from the divider card. The feed into it is roughly the same while cutting as well. It's a burntable and its a hobby so if I can get a thc that keeps the head from crashing due to warping or uneven parts that is my main priority. The Proma was cheap and Al from Eagle Plasma is living about 3 hours away and has provided 110% customer service and support. I was able to bring my computer and controller up to him, I started as an advanced idiot at best and left with a decent understand of how it's all supposed to work as well as modifying the mach3 and sheetcam to work better. None of that was done by Burntables, "just turn the knob" It's even possible the all of my problems with their THC were from the current voltage issue I'm having now, but even after I asked a ton of times what else to look for, the answer was "put in new consumables and adjust the knob". there were some other issues as well and I tried the "kill them with kindness" approach since they built the machine so they should have been my best shot at getting it running. Ended up having to send them a letter from a lawyer in the end....
Water under the bridge now though. Expensive lessons learned and my next machine is going to cut with carbide not plasma.

[tcaudle]

Since the BT THC lacks even the basic voltage feedback (readout) its about all they can tell you . With no feedback from the voltage being displayed there is no way to point out it not getting it from the Plasma. With no voltage isolation between the control and the plasma torch its possible SOMETHING can get a voltage spike and burn out and that hen can destroy downstream components. At one point BT went into the Hypertherm and modified how the voltage divider worked. Check for anything being soldered in at the CPC connector or back where the 20:1 cable plugs to the main board from the secondary divider card.

[D-chit Worx]

i cant get my torch to fire when it starts cutting so i watched the youtube video on the plasmatherm 45 and splicing the voltage divider between j22 and the work cable and that seemed to do nothing and right now im discouraged any tips would be appriciated

[tcaudle]

splicing the voltage divider between j22 and the work cable and that seemed to do nothing

Now that modification is a new one to me. The voltage divider connections have nothing to do with firing the torch . The hand torch lacks the internal jumper to allow the torch to be fired from the CPC. YOu have to simulate that jumper in the unit but its not part of the voltage divider ot the Arc ok lines.