DIY CNC Router / Mill

Umang Gajera

12 years ago

Project Bootstrap – (Yet another xD) DIY 3 Axis CNC

Project Bootstrap is OCFreaks’ 2nd Official Project which is – a Homemade DIY CNC Routing and Milling Machine.

For those guys who are new to CNC and related stuff lemme give you a formal introduction to ‘CNC Machine’ :

CNC stands for ‘Computer Numerical Control’ and that might confuse you even more. In its simplest form a CNC is an automated cutting-n-drilling machine. It can be used to cut, engrave, carve, mill,.. metal or wood or plastic , etc.. in the way you want. You design your 3D-solid using a CAD software. Then you convert that design into a format called ‘G-Code’ which a CNC controller software(CAM) understands. This CNC Controller software controls the Stepper motors on each Axes. The cutting head can be anything from a router(spindle), Laser cutting head to a Water Jet cutting head and also an extruder too which prints objects i.e your CNC becomes a 3D-Printer! To cut 3D-solids a CNC needs to have at least 3 Axis. Adding more Axes to a CNC enables you to cut more complex objects which is not possible using a 3-Axis CNC.

Link to CNC on wiki : http://en.wikipedia.org/wiki/Numerical_control

It all started when I entered into Robotics & Embedded – Somewhere around in late 2009. Back then I was working on a Hexapod Robot project. I had made a new design for my hexapod and then was faced with a challenge. How do I cut the design ? I had to do it manually or get it fabricated. Pro fabricators wont accept such sample quantity jobs. So I had to manually cut the parts for my hexapod .. Damn! During that time a random thought came in my mind – Why not make a CNC router and cut parts for robotics projects at home? I was like .. hmmmmm .. but making a CNC is tough ask. For months I was still like .. hmmmmm .. can I make it? can I really make it? Finally in April 2012 somewhere around my birthday I decided – Enough of this ‘can I make it? crap’ , Lets start freaking buildin’ it. After my exams in June 2012 I started researching on DIY CNCs seriously .. I mean damn seriously .. endlessly going through CNC related stuff for hours n hours n hours. My CNC story starts from here! My CNC project is divided into Intervals – each interval has its own story to say.

Interval 1 : INCEPTION (& Research)

Interval 2 : Part Selection and Sourcing

Interval 2A : Lead Screw , Lead Nut and Bearings Selection
Interval 2B : LM Bearings , Couplings & Motor Selection

Interval 3 : The Design**

Interval 4 : Ze Assembly & Electronics

Interval 4A : Ze Assembly Phase**
Interval 4B : Ze Custom Electronics

Interval 5 : Final Calibration**

Interval 6 : PCB Engraving Test**

Interval 7 : …In Progress…**

Note : ‘**’ => Post has not been uploaded yet. It will be online soon.

Here is Quick Video of Interval 6 : Here I’ve used the CNC to engrave text on PCB Copper Clads:

So .. What next in pipeline? : 2nd Version of the current CNC and a 3D-Printer!

The CNC Build in a Nutshell(sort-of)

6mm Thick Wooden Plates cut as per Design:

Drilled Sandwiched plates with effective thickness of 12mm:

Base aluminum frame:

Anti-backlash Lead Nuts , Regular ball-Bearings , Thrust Bearings & Couplings , Shaft and Lead Screw end support blocks:

Cut & Drilled Aluminum Angles of thickness 2mm:

Open and Closed type Linear Motion Bearings for Linear Motion:

Nema-23 18.9Kgcm Stepper Motors:

20mm Shafts , M10x1.5 Mild-steel & Stainless-steel Lead Screws:

Fasteners:

1st Prototype of Opto-Isolated Parallel Breakout Board – Sadly this prototype failed and didn’t make it ): [2nd Prototype in Progress (:]

2nd Prototype of DRV8825 based stepper motor driver – This too didn’t make it since it had a few bugs ): [3rd Prototype in Progress (:]

5mm Thick Aluminum Angles for reinforcement:

Anti-backlash Lead Nut Housing:

Lead Nut where it should be: When the Lead Screw rotates the Lead Nut moves back-n-forth i.e it converts the rotational motion of stepper motors into linear motion.