Picture of 3 Axis Arduino Based CNC Controller
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I've been playing with different CNC designs and Stepper controllers for many years now. I started building CNC machines long ago. My first inspiration came from Bruce Shapiro’s eggbot. I tried a few variations of it and even the board from evil mad scientist. Recently a project named GRBL came along that caught my eye. It used an Arduino to do the G-Code Interpretation. It still outputs step and direction pulses so all my existing designs worked fine with it.

The latest generation controllers I have built all use the same simple and cheap IC's. A pic 12c508 as the basic stepper driver logic and some H-Bridge chips that were originally meant for mundane things like tray loading motors on dvd players. I got a couple of hundred of these on ebay. The pic micros were from a guy that used to do mod chips with them but sold out his stock of unused chips really cheap.

I've used the cheapest parts I could find and still got great results with modest fine tuning. I used a dial indicator to see how bad my table was and it only varied .008 inches in depth from end to end. If I had used a surface planed board or aluminum plate that would have been better. I could always just mill a huge squared spiral pattern into the table to make it perfect
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Step 1: Single Board or Multiple Board Modules

Picture of Single Board or Multiple Board Modules
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I've tried both ways and each has its advantages. I always keep the 110V SSR board separate. When using the single board approach I like to use an Arduino nano clone. when using multiple boards I use and arduino prototype sheild wired with a bunch of headers for the individual boards.

Step 2: Control Buttons

Picture of Control Buttons
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I found these nice buttons in a surplus shop so I bought a bunch. A scrap of aluminum angle iron, a drill press,  and a bandsaw made a couple of quick panel.s You can easily do this with a hacksaw and hand drill.
blackboy_jakk3 months ago

Are you use stepper motor driver?
And I want blueprint of circuit board,Can you show?

steelspark6 months ago
Inventables sells a aurduino g-sheild that fits right on top of the aurduino and will control a 3-axis cnc if that helps anyone. It is what I use.
rjkorn (author)  steelspark6 months ago

Yeah I looked at a lot of those but many use the little stepstick driver chips. they like to overheat. These big SIP's easily transfer heat out. I've run the thing for 7-8 hours straight and the heat sink barely got warm. I could leave my hand on it comfortably. I wanted to do some long jobs. I guess it a matter of your intended use. My next big job is a Gallifreyan plaque for my sister. it might be the longest one yet but I wont have to worry about overheating the controller. I added an Air jet to keep the bit cool too.

prophead11 months ago
Great job with the details and explanations. It's answers many questions and makes a terrific roadmap for anyone trying to learn.
rjkorn (author)  nacon199611 months ago
(removed by author or community request)
rjkorn (author)  rjkorn11 months ago

Code and schematic for stepper board is here:

Protoneer rjkorn11 months ago

Thanks @rjkorn for the mention. I have actually designed a nice little Arduino Shield that uses GRBL(G-code interpreters) to control CNC machines. All that is needed with the shield is an Arduino an some Pololu Drivers.. :)

Here are a few helpful links:

Gabse rjkorn11 months ago

yes could you please upload the schematic and the code for the pic, that would be very helpful.

pfred2 rjkorn11 months ago

Looking forward to seeing the schematic.