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Computer-Controlled Machining B

Group assignment requirements

The group assignment for this week is the following:
- Complete your lab’s safety training
- Test runout, alignment, fixturing, speeds, feeds, materials and toolpaths for your machine
- Document your work to the group work page and reflect on your individual page what you learned

Large format CNC router machine specs

A picture of your large format router machine

Describe/list the available features and key settings of your large format CNC router machine.

Machine name:
Spindle max speed in RPM:
Machine bed size (work area):
Toolpath generation software used:

Safety

Describe the safety measures around using your cnc router machine. Safe distance, ear protection, eye protection, respiratory protection, what not to do or wear around the machine, suction, safe materials, etc.

A picture of the PPE used
A picture of the suction machine
A picture of safety related posters or things to consider

Materials

At the lab we use the machine to cut different materials such as:
- [Material] up to a thickness of [thickness] mm.
- [Material] up to a thickness of [thickness] mm.
- [Material] up to a thickness of [thickness] mm.
- [Material] up to a thickness of [thickness] mm.

For this assignment and this week we will be using [material] with a thickness of [thickness]mm. All the testing is done on this material.

Fixturing and machine setup

describe the process of fixing the material on the machine. What do you use? nails? special fixing tools? show what you use and explain why and how you use it and where to install it.

A picture of the material fixing process
A picture of the material fixing process
A picture of the material on the machine after fixing

After making sure the material is securely in place, we continue the machine setup process.

Describe the process of setting up the machine after fixing the material. Show the process of replacing the bit & zeroing the axis including the Z axis.

A picture of the bit changing process
A picture of the bit changing process
A picture of the Z zeroing process
A screenshot of the axis zeroing process on the controller/computer screen

Toolpath generation

Describe and showcase the steps needed to generate toolpath for your machine. Generate a cut/engrave toolpath for ~6 squares with different feeds and rates and showcase the steps taken to generate the toolpath. Do NOT go too far above or below your lab’s pre-determined speed and feed as that can be a safety hazard

A screenshot of the toolpath generation
A screenshot of the toolpath generation

Speeds, feeds

To find the best speeds and feeds for the material being used, we tested multiple speeds and feeds for cutting and engraving to see which gave us the best results.

write on each piece the speed/feed setting used

A picture of the results A picture of the best result

By completing this test, we found that for cutting [material], with a thickness of [thickness]mm, using a [diameter]mm bit, the best settings are the following:

Feed rate:
Spindle speed:
Plunge rate: Pass depth:
A screenshot of the tool settings used

Runout & Alignment

Runout is the deviation in the tool/spindle from it’s true circular rotation. Where it will no longer rotate on its intended axis. This can be measured with a dial test indicator.

Axis alignment ensuring that the machine’s axes (X, Y, and Z) are properly aligned and in parallel with each other. Misalignment can result in inaccuracies, poor surface finish, and other issues in the machined parts.

cut a ~large square on the machine

alignment test

To test this, we cut a simple square and measured the square at multiple ends. If the machine has perfect alignment, the square should be the same dimension if measured from any side. We measured the square from multiple areas and found the difference to be [measurement]mm.

reflect on if this is a good result or not.

A picture of the alignment test
A picture of the alignment test
A picture of the alignment result

Sources

Source 1
Source 2
Source 3
Source 4


Last update: May 11, 2024