Hi Andrew (Shad71),
I've been working on my own very fully featured DIY THC for quite some time now but it will only be a basic THC UP / THC DOWN signal sending type, nothing like your Simplicity with fully external PID control. I recently bought some cnc software and did some testing with a logic analyser to test reaction times of certain features. Unfortunately, I ended up devastated after my testing revealed one of the most important plasma functions did not work as advertised and effectively made the software useless (for my needs) until they fix that particular feature.
So until that's fixed it's back to Mach3 and the first THC I'm considering is your Simplicity (my THC has been designed around and talks to the other software, not Mach3). As has been previously mentioned, what interested me in your THC is:
1). Torch refire - I've needed that one a few times.
2). Voltage sampling – I believe Candcnc had problems and abandoned theirs
3). THC disable input
4). Hole centre marking feature - I designed a board to do that very thing 1-2 years ago, so obviously that's important to me.
Some questions I have on the Simplicity are:
1). Does the Simplicity not have the Puddle Jump feature that is in your other THC
2). What is the time delay from receiving a THC Disable signal to Z step pulses stopping.
3). This question is about synchronous Torch on/off switching. I.E. can this be done with the Neuron. If I want to turn on the torch synchronously with XY motion then I’d have in the gcode:
X1 X moves 1mm
M11 P3 Turn on output 3 at next motion move
X10 Motion move, output 1 turns on at beginning of this move
Likewise I want to be able to turn the torch off before the end of an XY move so I program something like:
M10 P3 Turn off output 3 at next motion move
X12 Output 3 turns of at X10 position and X moves 2 more mm
The above means the Torch On signal (output 3) must “pass through” the Neuron without any “significant” delay (i.e. very quickly). Also the Arc OK signal is irrelevant in this case because XY motion must start/continue without any Arc OK present, BUT the THC would need to enable THC after the torch has switched on and disable THC before the torch is switched off. I also realise you can't have the torch refire feature when doing a synchronuos fire with motion. You simply rely on the torch firing first time.
Can such operation be accomplished with the Neuron in addition to the normal starting using M3 and Arc OK.
So what is the purpose of all that ??
Open lines on thinner sheet and avoiding the round pierce holes by starting a pierce with motion.
Likewise turning the torch off a mm or 2 before the end of a cut to avoid a blow out divot.
Similarly hole cutting where users often get a divot as the plug drops out. Switching the torch off before motion ends prevents this divot.
Thanks,
Keith.