Computer Controlled Machining

This week we used the CNC cutting machine, to model cut big deisgns.

Group Work


The Group work focused on understanding the CNC machine and how it works; adjusting the settings and each setiing influences the material cut.

What is CNC Machine:-


CNC Machine: Computer Numerical Control machine. Is an automated machine that runs by a pre programmed commands that is cotrolled by a computer.This technology is operating complex tools, such as grinders and lathes, mills, and CNC routers. It can execute three-dimensional cutting projects with a single set of instructions.

CNC machine Testings: -

We did the following tests to understand the operation of the machine, the possibilities of trials and errors, the considerations tht has to be taken, and how to set the machine to make our design.

- Testing The Machine Alignment

To ensure the cutting processes run smoothly; alignment tests should be done every once in a while.

Alignments failures leads to several problems, such as, machine failure, machine gears failure, insufficient energy consumption and much more.

* Laser Alignment

Laser alignment, is a precise and simple method to align the CNC machine.

It operates by directing a laser into another sensor. This sensor sends data to a device, which decodes it and gives the correct data to modify the equipment's. The test runs on several points and axis to test the alignment of all the directions the machine goes to.


- Testing Speed and Feed Rate

Speed Rate (SFM): it measures the distance the needle moves per minute, the higher the rate the more area in a linear distance is cut.

Feed Rate (RPM): The rotational area per minute of the spindle.

Increasing those rates is not necessarily sufficient, as those rates results are influenced by the cut material and the material of the bolts that are cutting.


- Testing Different Toolpaths

Toolpath, is the data given to the CNC machine of the direction and movement of the cutting.

2D Profile Toolpath:-

Profile machining is a flexible cutting that give the option to cut along, around, over and undercut the items in good quality.

The cutting path can be on, outside or inside the vectors of the items.

Pocket Toolpath:-

Pocket toolpath is for creating 2d pockets by cutting the inside of the design, it compensates the tool geometry in both diameter and angle.

It is best for engravings designs, carvings and designs that have depth rather than full cut.


CNC machine safety measures: -


- Wearing safety equipment's like; safety glasses, gloves and safe clothes. For clothing, we should avoid wearing slippers or any other exposing footwear, avoid wearing dangling clothes or dangling sleeves as it is better to avoid wearing any thing that might cause to be stuck on the machine.

- Keep a distance of at least one meter from the machine when it is operating which is guided by a yellow line on the floor.

- At any time, if the machine is not operating properly or in case of an emergency there are two safety buttons to immediately stop the machine.


Preparations before the cutting phase: -


Cleanness of the machine

Making sure the CNC machine and free from dust or leftovers from previous cuttings.

The machine has its own vacuum and it is used to clean it.

Preparing the wood for cutting

The material that is used for the test is plywood, and when we placed it on the machine, we drilled it on multiple points to ensure it does not move during the cutting phase.


Cutting phase and final result: -


Cutting the wood




Cleaning the dust off the wood.


The resulting wood scraps depends on the machine settings. The more accurate the cut and the softer the wood scraps.


Final result:


Individual Work


The deign had to be something big, so I started looking for inspirations online. I came across a multipurpose table design. The table dimensions are based on the standard size of a table, and the design is flexile; it can be put on different angles and positions to accommodate the need of the user. It can also be easily dismantled and connected for easy use and storage.

Preparing The Table Design

I used Fusion 360 to make a parametric table; to easly modify it if the design don't fit together after the cut

The 3D model: -

Click to download the chair file!


Preparing the machine setting for the cutting

- For the joints I choose T-bone to easily assemble the pieces together and when they are joined the features are hidden.

- For the tool path, I choose the 2D Profile, cutting outside the design lines to minimize the material waste.

Cutting the wood and assembling the pieces.

I followed the same steps as we did in the group assignment: -

1. Cleaned the machine from any previous dust and leftovers.

2. Drilled the wood to stable it.

3. Operated the CNC machine based to settings done.

4. The machine started cutting and it took around 2 hours.

5. I removed the pieces and started to clean off the dust.

6. Assembled the pieces.


When I tried to assemble they did not fit together. Therefore, I sanded the wood on the joint areas to smoothly enlarge the spaces, I also sanded the shapes from the side to smooth out the edges.