Question Using Linux Software Toolchain

Hi Rory

"can you define what is a "real CNC controller"? So we are all talking about the same thing?"

Depends. I have developed CNC-systems for industrial and medical applications in the past. So I might have a different view on this topic.

A "real" controller is also capable of handling different parameters of attached motors (i.e. differnet current settings, decay modes...)
A "real" controller is also capable of handling different interfaces.

So I'd say that the SC controller is a simple controller (parallel Port version). Can't say much about the USB Version. But as this version is bundled with the software I guess it has more "intelligience" built in.
E.g. is has to handle real time events, which are handled by the PC if you use LinuxCNC.

"This is the CAM package. IMO it is much more than a converter. There are many many ways a CAM package can output Gcode. A better term perhaps would a "toolpath generator". "

Yes, you are right. I try to keep it simple as Jubin seems to struggle with all the tech bla bla.
Which is by the way something I still hate about the Linux community...

Well... a lot of tech was raised up here!

Foremost I have to say one stupid thing: "Win PC" is absolutely misleading and confusing as name, it is a no-sense name for a product in my opinion. But this is just my point of view, just for the records.

I appreciate the long description made by Rory, now I understand that for his point ov view the "CNC Controller" indicates a pair: controller board + controller software.

CNC Controller = Controller Board + Controller Software = e.g. = Win PC USB module + Win PC Software

One cannot exists without the other and viceversa.
I could embrace this vision, no problem. Even if my industrial background (electronic High School) forces me to think at a controller like an evolute/intelligent autonomous piece of hardware.

Now I'm confused about the Win PC Starter, MagIO2 says that the starter version cannot handle g-code at all. One has to use the Stepcraft like a plotter just for engraving (by the way, that is absolutely not clear by browsing the website).
In the Rory's vision this absolutely correct: you don't have a CNC controller (couple hardware + software) so you cannot pretend to have a milling machine. I'm ok with this, no problem.

But after I discover (thanks Aldronaig) that I could do some milling by using just the software part of a controller (i.e. the LinuxCNC).

So, in one case I have no controller hardware (Win PC starter solution), in the second it magically appears (LinuxCNC solution). The device (the Stepcraft machine) is the same in both cases.

I'm a little bit confused...
I appreciate that with the "USB version" (even if I find this denomination quite misleading) I get a full packet for 2.5D milling (with an optimized control hardware for best results), at the same time seems that one cannot do 2.5D milling without buying that version. Which seems not true.

@Aldronaig: Honestly I have no idea if WinPC (starter or full) can run with Wine or not. Furthermore I don't know if performances are a fundamental requirements to use it.

Hey everyone,

yepp and there might be bit of misleading factors due to the definitions in english and german language.

I agree with julius on the autonomous part. Normally a controller can be fed with some sort of instructions and does the rest. This is true for the parallel port version. But I don't know if the SC controller board is capable of driving e.g. a modified SC with different motors which e.g. a "regular" controller can (I've used a standard off the shelf controller with my SC 300 and it worked fine after some tinkering).

So in conclusion: parallel port & Linux CNC and you can use the SC as a milling machine (manual control via keyboard, joypad or manual GCode input)

SC parallel & LinuxCNC & CAM (e.g. dxf2gcode) and you can use the SC as a "real" milling machine which uses your CAD drawing and mills the part as drawn (2.5D and 3D, maybe also 4D but that would be a different topic).

WinPC is a really good software/hardware bundle for ppl with no knowledge and no time to digg deeper into all that CNC theory. And a cheap one too! If you use Windows o.c.


@julius I don't know either. I assume that it might be possible because alot of the real time events are taken care off by the WinPC hardware. Some ppl. have used WinPC-NC via WINE but with a different CNC machine.
But don't quote me on this! I really don't know.

Boy, this thread really starts getting confusing ...

Consens so far:
The big PCB in the stepcraft is a driver. It's only purpose is to drive the steppers according to the control signals it receives on an interface. Things like motor settings are fixed and can not be controlled at all - well at least not without hacking.

Here is the point:
something has to generate these control signals. And whatever generates those signals is from my point of view the controller. In the combination USB board/WinPC NC the controller is given in hardware (and the software running on the uC of the board). The software running on the PC is only a GUI for "manual" movement, displaying position and for sending the g-code or plt file to the board. The whole controlling-part is done on the USB board.
The same is true for the Arduino/EstlCAM combi.

A real autonomous controller would need a user interface and a way to read the g-code-files. Big CNC machines have their own monitor and a disk-drive or SD card slot to feed it with the files. But real CNC machines also might include the CAM part.

This kind of controllers would increase the cost dramatically.

In Mach3/LinuxCNC and parallel port combi the controller part is included in Mach3/LinuxCNC.

Hi MaglO2,


to keep it simple and stupid: yes.

MagIO2 wrote: Boy, this thread really starts getting confusing .../quote]
Thanks MagiO2 now it's all perfectly clear.

I hope that in future Stepcraft will post/publish a simple block diagram to explain what we said to untalented CNC-rookies like me. I think that an image is better than one thousands words.

tschussss!

I'll work on this for you guys when I get a chance.

@Aldronaigh

about LinuxCNC control software: I heard that you need a very good graphic card for your PC in order to use it. It is true?

Hi julius,

that is not quite right. It also works with onboard video IF you get some things right (BIOS/EFI setup etc.).

I use a HP 7800 SFF and it works perfect and I event haven't tinkered a lot. (also you might get them cheap as they are coming of lease these days!)

The problem is with all the real time events and how they get interrupted with interrupts (lol) via e.g. onbaord video, onboard audio etc.

The worst thing for LinuxCNC are notebooks (not recommended at all).

But on the LinuxCNC homepage you will find a list with tested hardware. The more you turn off, the better. So the simplest PC is the best, generally speaking.

What I have figured out so far: a Pentium II from a brand name manufacturer e.g. ASUS would be good one.

But there is a test program in the download area which you can use to test different PCs before you buy them.

Hello,

actually, after that I wrote the post above I've googled for a while and I've discovered a lot of guys having no problems even using on-board graphic card.

I've two old desktop PCs from my old office, I want to use one of them as dedicated "controller" of the Stepcraft. So it will be used just for machining, no internet browsing, no videos, no skype, nothing.

processor AMD Sempron 1Ghz
ASUS motherboard (I don't remember the model)
ram 1 Giga
HD 80 Giga
1 parallel port
Embedded videocard 1024x768

Seems that it should work to run LinuxCNC.

Uh! I've found the list of tested hardware !

Hi julius,

yay! Sounds like a good setup.
If it works, please submit your data to the homepage. It's not a must, but it helps ppl to get the right hardware.

Onboard graphics these days seem to are less of a problem than years ago. Maybe it has to do with methods used for memory sharing which are different these days.

Just ensure you turn off everything you wont need. E.g. onboard audio, ethernet, USB ports, internal drives etc.

Hello,

Note: Drop a message in the thread if you are interested!!!!

Finally i got my stepcraft after a quite long delivery time (7 weeks). I initiated this thread before ordering the machine in order to be ready when it was delivered.

After looking the electronics. After reading several threads in the forum. My conclusions conduct me in doing the following things:

- Stage 1
* Attach an arduino + grbl-shield and the software relevant in place of the USB small board

- Stage 2
* Replace all the electronics whith an arduino mega + ramps (or equivalent)

Motivation:

- I requested early the technical specs of the power board to stepcraft with out result. If any body have the pin out for the power driver board. I will appreciate. Also pictures face and back from the parallel adapter will help too.

- The WinPC-NC starter software is window. I run Linux.

- The WinPC-NC starter is less than "start" based on the comments in the forum. The cost for the full product is 200€.

- The arduino + grbl shield cost 40$ in ebay + a 20-30$ power supply if needed
- The Mega + ramps cost 80$.

In both cases the total cost is a lot less than the full WinPC software and open the stepcraft to the Linux software suite.

Hi Jubin,
eight years later, I found this thread and I’m curious whether your plan (still) works as intended.
How complicated was it to set up?
Thanks in advance!