Newbie - what Mesa card to choose?

Hi all,

I decided to build myself a CNC router a while back and started to go down the path of designing and building a machine without a lot of thought to how to control it. Since then I have also realized I am not a very good machinist and have struggled with making highly accurate drill holes.

Here's my thought process to get me doing some CNC projects much faster yet not giving up on my CNC build
1. There is a person who lives in my town selling a no-name 6040 and controller box setup with a parallel port connection. I do not want to go down the Mach3 route for that router or my new one so I am most interested in Linux CNC. I'm an IT guy and while I am no expert at linux I can navigate well enough and am not afraid to learn more.
2.. I have several older PCs which all have parallel ports and can load linux on those boxes.
3. get the 6040 up and running using linux CNC - do what-ever board changes it requires to reconfigure the 6040 control box so as I can use the 6040.
4. Have some fun doing some basic CNC projects - Learn!!!!
5. When I get good enough to mill some aluminum gantry, end cap and z axis panels and make them up on the 6040
6. Setup the new router with new stepper motors and the same output cabling so I could re-using the 6040 control box.
7. Switch the control box back and forth until I am comfortable with new router.

Questions:
1. Is my thought process logical? aka reconfigure the 6040 box to use linux cnc?
2. Could I just load linux cnc on a PC and connect via parallel? or does that require a mesa card which would output to parallel?
3. If 2 requires a card, would I just be better off reconfiguring the control box to use a 7i76 card and bypassing parallel all together?

thanks in advance

TLDR
Yes you can use a PC with just a parallel port to control the machine and LinuxCNC will happily use it.

It's not a bad plan. You may run into a hard time finding good documents about the no name 6040 and trying to interface it. It shouldn't be too crazy but it will have some moments.

For the extra $120 you could probably just option into a 7i96 off the bat and not chase down an old pc that works with good latency. Run it off ethernet. Just need a decent pc. Lots of options out there.

Thank you both for the info

I have an Dell workstation that isn't too old 4 core 8GBram, runs win10 fine, I ordered up a 120GB sata SSD and cage to install it in a larger drive bay, should be here in a couple of days. In my stack of old crap, I even have the right parallel cable to work with so I am going to try that first.

In the mean time I downloaded the linux cnc iso and setup a vm in hyper-v to mess with it while I am waiting.

I haven't bought the CNC yet, meeting the guy tomorrow night after work, from talking with him, he seems like a decent person, and had bought this router to do similar to what I am planning on doing, You can even see the pattern of his new gantry panels in the waste board.

Once I get the cnc setup home and can crack open the controller case to see what I have to work with, I will re-evaluate switching it to ethernet, the $120 option won't break the bank.

On the topic of ethernet, the videos I watched on the mesa cards said that it could be only direct attached straight IP/same subnet, do you need a crossover cable for that purpose or do folks use a small 4 port switch not connected to the internet?

Mesa 5i25 or 6i25 or 7i92 are cheaper and are a direct replacement for two parallel ports, but at much, much faster rates and more versatile.
Since it is a small machine it will not have spindle control or limit switches, so it might be better to get one of the above now and later add a 7i76 to have all the bells and whistles.
Mesa uses a straight CAT5/6 cable, although almost all newish PC have auto negotiation on ethernet ports so cross cables are pretty much useless.

let's see if I am understanding this correctly, here's the options as I currently understand it, please correct my errors

If I don't want to crack open the existing 6040 cabinet but want ethernet - purchase 7i92 - outside card, ethernet goes in and parallel out to control box

part to order - store.mesanet.com/index.php?route=produc...uct_id=306&limit=100

If I want to avoid parallel port altogether and upgrade communications method but will require reconfiguring inside the cabinet. This requires a desktop and a PCI port to install the card
7125 / 5125 kit
parts to order - store.mesanet.com/index.php?route=produc...83_84&product_id=215

If I want to go ethernet and don't want an internal card in any PC - here's where I don't understand clearly.......

It seems like to get all the capability I would want something like

7i76 - not sure which version will allow adding connections and which type of connection - I think the difference is base if I supply power to limit switches and the ground is on the board or if it is the other way around.
part to order - store.mesanet.com/index.php?route=produc...uct_id=290&limit=100

Cheaper option but less flexible 7i96 - I'm guessing less ports and if I wanted more I could get another daughter card
part to order - store.mesanet.com/index.php?route=produc..._id=311&search=+7i96