Hello (First post), please send me in the right direction

  Hi,First post, I have zero experience with LinuxCNC, I came hear to get educated.I previously did a CNC conversion of an old round column mill using steppers and Mach3 (about 10 years ago). I'm an electrical engineer by training so hopefully that will help.I have a new 8x30 knee mill and I want to try LinuxCNC this time I have near zero direct experience with Linux. To be clear this is for hobby use so I would like to use low cost components wherever I can get away with it, I won't be making NASA type stuff just hobby stuff so if the machine approaches 0.001" repeatability I will be very happy. I'm swapping in ballscrews at this time.System as I envision:

• Four x  T6 ac servos, AFAIK the controllers for these accept step and direction pulses much like a stepper and take care of closing the loop and are provided with some form of tuning software (yet to be tested).
• 8 limit switches
• Spindle speed encoder
• Scales possibly up to four
• Eventually I will make a custom control board for jogging etc, but hope to use GUI for the short term

Hopefully someone can answer my preliminary questions:

1) For a CPU board, what is powerfull enough?   I have a RPi, not sure if that is even close to powerfull enough. I also have more of a PC type SBC EPIA Nano-ITX not sure if it can run Linux?  Suggestions for a suitable CPU board please?

2) I can randomly start reading posts, however if there is a starting from zero tutorial somewhere, please provide a link and hopefully I can come back less clueless with more focused questions?

3) What version of Linux should I be loading on the CPU board? is it free?

4) Suggestions for required break out board, someone suggested Mesa 7196S, not sure if there is better or cheaper. I'm all ears?Image of my old custom control panel that I made for my RC mill quite some time ago.Thanks in advance
 

Download the ISO from the download page, write it to a USB stick, see what boots from it and run some latency tests without the base thread. That is how you decide what PC to use since you have several.
As for Mesa, i have no affiliation with them, but having used a lot (probably over 80?100?), i gladly advise to go for it, they are extremely reliable and have the best support on planet earth!
7i96S should do fine, and it can be extended/expanded a lot at any point in time if you need it to.
As for reading posts, get the ISO, boot from USB and test, everything works from a Live boot (without installing it) so you can get a feel for it and have a look at different GUI's included with LinuxCNC.
Edit:
You can always use a Parallel port if any of your PC's have it, and later upgrade to Mesa, but parallel port is quite limited.
Still, very good for making a usable machine and learning a lot in the process.

I'm about to order a MESA board, trying to decide on 7i96s or 7i95t

For the extra $100 it seems like the 7i95t is better for future proofing (not running out of I/O)

Is there any reason not to go with the 7i95t for example possibly less mature or support on this forum if I need help?

Comments much appreciated.

I think the 7i96s will be fine, particularly now the S version has 0-10 volt spindle
I just refreshed a reference build sheet for the 7i96 to be for the 7i96s with spindle and have attached it.
Note that  it includes min and max limit inputs but when I built a mill, I only used home switches (which would free 6 inputs).

You still have a lot of expandability via P1 and the smart serial if you need more down the track.

 

Ooops, did not change the title in the Document to 7i96s

tommylight wrote:

Download the ISO from the download page, write it to a USB stick, see what boots from it and run some latency tests without the base thread. That is how you decide what PC to use since you have several.

 

I'm going to pickup a HP Elite 8300 SFF today to use as the PC for this project (HP 8300 recommended by MESA)

1) Assume I'm starting with a blank SSD with no operating system. Am I correct to assume, I need to load Linux OS before the download the ISO stated above, or does the ISO include the Linus OS?

2) Link to ISO?  (So I get the correct one)

Much appreciated