8. CNC machining¶

This week i was introduced to cnc machine and how to operate it, as a group we were assigned to do a small project. Individually, I was assigned to create my own sketch using fusion 360 to cut MDF wood 2440*1220 mm

Definition: CNC machining is a manufacturing process where computers control the tools that create custom-designed parts and products.

Group Project¶

Safety procedure¶

1 Wear safety glasses to protect your eyes from flying debris.

2 Use sound-isolating headphones to safeguard your hearing.

3 If you have respiratory issues like asthma, wear a mask to avoid inhaling harmful dust.

4 Roll up your sleeves to prevent them from getting caught in the machinery.

5 Maintain a safe distance behind the marked line on the ground when the machine is in operation.

6 Remove any objects that could interfere with or get pulled into the device.

7 If an issue arises, you can quickly shut down the machine by pressing the emergency stop button, located either on the machine itself or next to the computer screen.

Runout¶

Runout means how much a spinning part wobbles from its center. To check runout, a dial indicator is used to see how much the tool moves as it spins. You can reduce runout by fixing or changing old tool holders, balancing the parts, and aligning the spindle correctly. Doing these things keeps the CNC machine’s rotating parts accurate and precise.

Alignment¶

Alignment in machines means getting all the parts positioned correctly in relation to each other.

Speed and Feed¶

Speed is how fast the cutting tool spins, while feed rate is how quickly the tool moves into the material. To find the best speed and feed settings, start slow and increase gradually, keeping an eye on tool life, surface finish, and chip formation. Adjust these settings based on the material, tool, and desired outcomes.

For MDF wood, using a spindle speed of 17,000 RPM and a feed rate of 60 inches per minute worked well. Testing and fine-tuning these parameters is key to getting the right results, prolonging tool life, and preventing problems like early wear or poor surface quality.

Material¶

The material being worked on in CNC machining is the main factor that influences speed, feed rate, tool choice, and setup. It’s best to test different materials and adjust settings based on how easy they are to machine. The chosen material should be suitable for the job. In this instance, MDF wood was chosen. Understanding the material and thorough testing are vital to set the right machining parameters. This guarantees top-notch part quality, longer tool life, and overall efficiency.

Tool path¶

Toolpaths are like planned roads for cutting tools in CNC machining. To make sure they work well, it’s smart to simulate them first using special software. This helps find and fix any problems before cutting the real piece. After simulating, testing a small sample cut is a good idea to make sure everything works smoothly. Based on the test results, the toolpaths can be adjusted to make cutting better and the parts higher quality. Testing and improving toolpaths are crucial to make sure the CNC machine works right and gives the best results for the final piece.