DIY CNC

gotcha, so I would just adjust it in LinuxCNC?

Yup! It may take some fiddling to get the speed you asked for to match the speed you get, but it should at least "just work"

I am not sure if Linux CNC is really cheaper than GRBL. 
 

www.grbl.org/single-post/a-peek-at-the-picocnc  This is an example based on the Raspberry Pi Pico, all documented and possible to recreate "in the flesh". I bought the Pico boards for like 3€ a piece. The base board was more expensive, but not too crazy. 

• slow simple 3 axis machine without linear scales or rotary encoders probably works just fine with the GRBL
  • When I think of adding things "slaved axis", "linear scales", "automatic tool changer" I would go for LinuxCNC 
     

The OP implied he already had a PC to use, which you'd need for GRBL anyway (unless you added an LCD, buttons, and an sdcard), so adding a parallel breakout board is about $10, compared to the $4 for the pico and whatever the picocnc costs (assuming you can buy it, I couldn't find one for sale, but web site says "retired", but historically $29 assembled). You need the same stepper drivers either way.

A Mesa board is way more expensive, yes, but you get a lot more for your money.

Exactly! The PC (raspberry Pi or similar), power supplies and stepper (or servo drivers) can be basically the same. What I think is that the mesa card is not worth it, when you stay with open loop stepper motors and the mechanical system is not made for high speeds. But once you start using the I/O and Encoder inputs it is a real help to have a system that is easy to use, supported and works (happy customer of Mesa Plug n go kit).
For the picoCNC I paid roughly (guessing) 130-140€. Some things come with minimum quantities, others are discounted. It ends up at approx. 30€ a piece +-. I would have just bought the successor of it for 50$, but shipping would have doubled the price. To me it was more about the assembly challenge than the actual need for it. But there are "ready to go" options. 

 


One aspect is that a 10 mm carbide endmill will cost roughly the same. 



 

So for metal working the tooling and material quickly gets in regions where a Mesa card is really my least problem and I bought a 2nd Mesa card after the first one.

#no advertisement just random pictures. 
 

I agree - for someone getting started, pay the $10 and get started.  I did that.  Just understand that you may outgrow the $10 option and need to get the $150 option (or in my case, the $220 option, and I'm looking at adding two more Mesa cards in the future).  The Mesa cards are in a completely different category of "cnc boards" and - if you need them - they're worth every penny, and cheap compared to the rest of the stuff you'll get.  But you don't need them to get started.
I think my only point is, if you already have a PC with a parallel port (rare these days), the $10 breakout is a better option than anything RPI-based, because it lets you get started with LinuxCNC, which has a better growth path than GRBL.  Assuming growth is a goal, of course

As for assembly challenges...  www.delorie.com/photos/cnc2/PXL_20231229_210308596.html (and it's gotten worse since then)

djdelorie wrote:

I think my only point is, if you already have a PC with a parallel port (rare these days), the $10 breakout is a better option than anything RPI-based, because it lets you get started with LinuxCNC, which has a better growth path than GRBL. 

I absolutely agree, thank you.

  My only concern regarding using my parallel port computer with a breakout board is the delay (hence why I was considering the mesa card). Hypothetically, let's say my jitter isn't a problem. Will my experience making chips be the same as with a mesa card? I want to make some pretty complex parts and am concerned that any amount of jitter could make that impossible. I've attached an STL file of a part that I want to make for a friend. Could this be possible using a parallel port, or should I just spring for the more expensive card?

IIRC the original parallel port could switch up to 1,000,000 times a second. Assuming two switches per pulse, 8000 pulses per rotation, that's 3750 RPM, which is way more resolution than you need (steppers are 200 steps/rot, or 3200 with microstepping), and way faster than big steppers can probably run anyway.
When I was using steppers and a breakout, it was the steppers that were the limitataion.

So I should probably start with my Dell first and then get a Mesa card once I feel up to it? Just to confirm, you are saying that you don't think it'll be an issue for making that part (assuming the jitter is not a problem)?