CNC Lathe

How well do those parallel port breakout boards work? I guess the sample rate would be much lower than the mesa boards but maybe good enough for ->low speed high resolution ->high speed low resolution ? is such a configuration possible in linux cnc? From what i read online the parallel ports solution seems to be harder to work with. I wouldn´t mind some extra efford as i have more time than money right now, but if it would be a nightmare i am ready to spend some more money.

store.mesanet.com/index.php?route=produc...oduct&product_id=343

Damn those specifications do look tasty. I would need to expand my budget quite a bit. Would there be any advantages (except beeing plug and play) performance wise? I mean the most demanding things i plan to do is cutting tapers or threads.

Yes they do!
Not aware of other advantages in performance.
As for budget, you can do a lot of things with just an old PC with parallel port and have a lot of fun doing it, then pushing things further and further and more joy will be there for sure ... till you start bumping into parallel port limitations and the spaghetti mess on table/in box from all the wiring !
You can skip all the painful limiting stuff a go for a Mesa so you can later bump into other limitations with other stuff !
Budget wise, maybe it is better to get a 7i92M now and a cheap BOB, or 7i96, or a 7i76E, or later add a 7i76 to that 7i92 (no cable required for the M version) and later add a 7i85 some letter here for the encoder version.

Thanks again for the advice, starting with the parallel port doesn´t sound so bad afterall. After years of tinkering with arduino i am used to spending hours troubleshooting chinese eleactronics lol. As for the spindle encoder, can Linuxcnc do this switch (from precise positioning to tachometer/rough positioning) at a given rpm? -> so the parallel port can keep up ? If not, a Mesa card would make a lot of sense

backyardengineer wrote:

Thanks again for the advice, starting with the parallel port doesn´t sound so bad afterall.

There is a lot to recommend starting there.

As for the spindle encoder, can Linuxcnc do this switch (from precise positioning to tachometer/rough positioning) at a given rpm? -> so the parallel port can keep up ? If not, a Mesa card would make a lot of sense

You could just let it lose position at higher speeds. I had a lathe that worked that way (parport).
It re-synchs to the index at the start of each threading pass, so it's not a huge problem.

I recently added missing-tooth index to the encoder counter, so you can do position and index with a single parport pin. (For your stepper-positioner I think you would need to work open-loop, though)