BoB for Plasma Table, steppers, THC

I'm planning out a plasma build and I need some advice. I want to have internal THC but I'm unsure what hardware is necessary to achieve this. has anyone had luck with a controller like this? for $8 is this a too good to be true kinda thing?
www.amazon.ca/Interface-Opto-couplers-Is...86126270&sr=8-3&th=1

My current setup is NEMA 17s with a Rambo board. I'm feeling the limitations of the Rambo and Marlin firmware. I need THC. Hence the upgrade to Linux CNC. I'm happy with the NEMA 17s but I'm wondering if the BoB I have selected can be used with NEMA 17 drivers. Can the same BoB be used for bigger stepper drivers if ever choose to upgrade (NEMA 23s? Bigger?)?

hi
the low cost board is not that bad
but on internal thc it will get you external cost
with a UP/DOWN thc it will work with that bob
the costs are higher then actuly goiing for a 7i96 MESA that can have a better outcome and a mutch easyser expand
Nema17 on plasma is not that best choce
use Nema24 at 4Nm to drive real quick and 48V Supply

there are low cost kits to fit your need

MESA 7i96 with a THCAD is a way better choice, it's expandable, has great support here and in LinuxCNC and not that expensive.

What 3d printer did you strip to have those parts ?

Lol, they are 3d printer parts. It's actually pretty impressive considering what goes into a MPCNC. Check them out if you haven't seen them before.

Anyways, can a THCAD be used with the cheap BoB? I read through the THCAD manual and I don't quite understand how it connects to the BoB and computer. Does the THCAD send out steps and dir? Or does it send out values to be interpreted in LinuxCNC? Do the parallel port pins send voltage to the computer?

Is the MESA 7i96 only ethernet? It looks like it has a PCI expansion. I was under the understanding that PCI was best. I thought I read that ethernet and USB are too slow. Is there a version with built-in PCI?

Mesa has the 5i25 and 6i25 PCI and PCIe cards. These then are connected to the mesa board of your choice.
Some of us are using small PC's with no PCI expansion bus.

Once installed ethernet and PCI for Mesa make no difference. Usually we run a 1 mHz servo thread in LinuxCNC so things only happen 1000 times a second. In between, the Mesa Hardware stepgens are still doing their job and Linuxcnc tells them to change frequency 1000 times a second if required.

Don't forget to factor in the cost of external stepper drivers.

Anyways, can a THCAD be used with the cheap BoB?

Yes it can providing that the optos are fast enough and the latency of the machine is reasonable.
The THCAD outputs a frequency that can be connected to an encoder which outputs a velocity that can be converted to a voltage level.
You would probably run the THCAD at 1/64 or 1/128 rather than the normal 1/32. Again this depends on the optos and the latency.
linuxcnc.org/docs/2.8/html/man/man9/encoder.9.html