Introduction: Entry Level DIY CNC TDKU I

After finish a project in IT job I was wondering what to do to use my skills and knowledge to learn and share how to design, build and show something useful. As the DIY and Maker culture is growing fast I decided to create a CNC machine because once we understanding how it works we can apply the knowledge to other machines like 3D printer, Laser cutter, etc.

I divided the construction into 4 steps called:

  1. Y-Axis
  2. X-Axis
  3. Z-Axis
  4. Motor base
  5. Electro/Electronics

General information:

Dimensions: 1075,5x1075,5x785,7mm (with Nema 23 10Kgf step motors)

Structure: 20mm thick MDF and flat-head wood screws. I recommend waterproofing the wood after cutting to try to avoid changes in dimensions and gaps in the connections.

Trail: 5/8" x 1/8" thick steel angle bar mounted over the MDF and fixed by round-pan head wood screws.

Moving system: bearings with M8 bolt, washers, and nuts.

Motor: Step-motor Nema 23 10Kgf.

Electronics: Arduino Uno R3, CNC Shield V3 Reprap, drives DRV8825 and 24V/5A power supply.

Software: Arduino IDE, GRBL library, bCNC

Design software: Sketchup Pro 2017, Inkscape, Makercam.com, SketchUcam

Attachments

Step 1: Y-Axis

Y-Axis steps:

  1. MDF structure.
  2. Left and right rails.
  3. Long screws and bearings for the Axis.

Points:

  1. The rails need to be very parallel.
  2. The nut for the axis need to be set without gap.

Attachments

Step 2: X-Axis

Steps:

  1. cut and drill the holes in the both sides.
  2. Bearing Set. You can find in the pictures the way that I used to calculate the distance between the rails to avoid gap in the bearings.
  3. M10 Nut Set.
  4. rails follow the same steps described in the Y-Axis .

Attachments

Step 3: Z-Axis

Steps:

  1. Cut and drill the holes.
  2. Install the rails.

  3. Bearing Set. You can find in the pictures the way that I used to calculate the distance between the rails to avoid gap in the bearings.

  4. M10 Nut Set for X-Axis and Z-Axis.

Attachments

Step 4: Motor Base

The support for the Step motor was made with 3 pieces of MDF 15mm and 6mm thick. The construction is very straight forward and you can find the materials and dimensions in the PDF files attached.

Attachments

Step 5: Electro/electronics

Steps:

  1. Install the GRBL library into the Arduino (https://github.com/grbl/grbl).
  2. Install bCNC (https://github.com/vlachoudis/bCNC).
  3. DRV8825 current adjustment (https://www.pololu.com/blog/484/video-setting-the-current-limit-on-pololu-stepper-motor-driver-carriers).
  4. Install the wires for the motors.
  5. Install the micro switches.

Attachments

Step 6: Test

Here you can check the cnc working.