As suggested in the other thread, I'll try to start a new thread covering the miriad that is CNC and the little experiance I've gathered in the last few years with Mach3, smooth steppers, UC100 UC300 UC400 controllers and UCCNC, pendants whatever.....
If you have a look at the Mach3, sheetcam and CNCDrive (uccnc) forums you'll no doubt come across my handle.... I've been a little prolific over there learning everything I possibly can. To be fair I've probably been a little too prolific on the forums, given the whole reason for me being involved in CNC, plasma whatever is my main hobby..... rebuilding the 90...... I've had another spurt with the 90 and putting it back together but that is another story for another thread.... I keep chipping away at it though (swmbo is getting a little.... err naffed ... given we can't move house till its done!!! JFDI.
I still have my plasma table (the one from the other thread of long ago that prompted Si to come up with his design), and it was used a lot.... less so of late, no reason other than trying to do gearbox marriage things). I have aquired a pneumatic scribe in the process, and a small 6040cnc router table for a bosch triming router for PCB's, and aluminium milling (but to be fair it's a little boarderline on ridgity for milling aluminium). Along with a 2.5W laser (for gaskets and paper templates..... quicker to cut a piece of paper to check sizes of plate before wasting good quality mild steel plate....) Oh yeah.... and a 4th axis for the plasma using one of these and a bracket to hold it to the frame along with a more powerful stepper motor https://ae01.alicdn.com/kf/UT8qqLMXCFaXXagOFbXI/Free-shipping-4-Jaw-100mm-chuck-font-b-CNC-b-font-font-b-4th-b-font.jpg complete with 4 jaw self centring chuck for SHS.
I started of with Mach3, and to be fair it was good, but had a few niggles which are:
1) torch off delay (for plasma) which basically allows of overburn at the end of the cut and a divot
2) macro loops which only run at 10hz..... (10 x per second is fairly slow when you are cutting plate at 6000mm / min, that is a 10mm travel distance)
These two clips decided it for me (plus my own experiance of Mach3 + Mach4 as I was into and still have licences for both .... plus two smooth steppers)
https://www.youtube.com/watch?v=25FtHEo4Ujo Note the hand turning of the syncronised spindle motion (does require an encoder which are now very cheap to obtain.... mach3 can ontly use a single spindle pulse)
Anyone starting out now, please please get yourself a UC controller (make sure you get a genuine one, as there are a few chinese listed uc100's which look nothing like the grey uc100 and simply won't work for some fuctions + they cost the same if not more than an official uc100). I have no vested interest in CNCDrive (company responsible for making and developing UCCNC + the UC range of motion controller) but when you consider how fast they fix bugs, sort issues and add features when you comare to Artsoft (Mach3 + Mach4 developers) really there is no contest..... [note Mach3 is not and has not been developed since ~2011 as it is at the end of it's life] Mach4 is comming on, but for those with plasma, laser applications the hardware (motion contollers) are not available to offer M10/M11 + Torch Height Control Fucntionality. The UC controllers also offer a free Mach3 driver should you still wish to use mach 3, but you have to buy uccnc (which is much cheaper than Mach3, but I say again you muct buy their UC motion controllers for uccnc to work).
Si asked about the THC (Torch Height Controller) I was looking at building..... well, I've had a Proma THC (please please please don't buy one they are carp!) and I've presently got a MiniTHC http://minithc.com/ which offers some good features (c-axis protocol)..... but it's not a Neuron THC http://neuroncnc.com/ which offers some good features too (nearly top notch). My THC idea has been visited a few times, but never completed, last time I looked at it was a few months back now as UCCNC offers some very good THC features (no delay for firing / stopping the torch), plus no delay for THC enable + disable macros and also you have additional no delay THC outputs to lock the torch if you use a Neuron which is fully external THC control other than settings being passed from UCCNC to the Neuron THC.
I upgraded from the Powermax 350 to a Powermax 45 which will do everything I'll ever need (although the PMX45XP offers some good features I would have liked.... modbus!!!) Oh yeah, UCCNC offers Modbus TCP/ RTU and ASCII protocols ..... (Mach3 is TCP & RTU only) ... plus it is very much possible to programme any Modbus type stack which does not quite meet the requirements of Modbus .... such as the very common chinese 2kW inverters for spindle speed control.
Plasma is not all about speed, it is actually all about acceleration and speed, but acceleration is by far much more inportant, given once the torch is set we normally have no way to control the torch current setting in these cheaper air plasma cutting machines.
If anyone if looking to buy a plasma.... first, buy one with blowback start!! (any hypertherm and any machine that uses the S45 Trafirmit Torch http://www.trafimetusa.com/Products/Plasma Range/Trafimet Torches/Brochures/EA0590_0702.pdf [possibly the S65 too], lots of them do). Next on the list, buy an HF start machine, lastly ..... scratch start..... I know of only one person who has managed to get a scratch start machine to work on plasma with a circuit mod and can probably point you to the thread.
You will also need some software to generate your gcode from CAD dxf drawings ..... Sheetcam is the way to go http://www.sheetcam.com/.... Les at Sheetcam (UK company) is very pro-active [suggestion.... buy your licences via lowcostcncretrofits ..... it will work out much cheaper .... they offer no support... you use the Sheetcam forum for that or RTFM.... http://www.lowcostcncretrofits.com/