Laser Cutting

Reflection on Laser Cutting tutorial lesson:

For Week 2's lesson, I was introduced to Laser Cutting. Laser Cutter refers to a machine that uses motors that are controlled by a computer to cut and engrave material using a laser beam. 

In a laser cutter, there is an exhaust that pushes CO2 gas away and air compressors are always switched on first as it serves as a fume extractor where CO2 gas is filtered then discharged to the surroundings. It also consist of an air assist to blow debris and reduce risk of fires. The safety precautions to take while operating the laser cutter are to not stare directly into the laser beam while cutting, not using materials that contains chlorine (PVC) or foam and to not leave the machine unattended while cutting/engraving. If a small fire occurs, extinguish it by blowing or removing the material from the laser cutter. If a material cannot be cut, it is important to stop and check as the focus lens might be dirty.

(DINFOS Pavilion, n.d.)

Vector graphics are scalable and has a small file size that consist of anchored dots and connected by lines and curves. On the other hand, rastor images are pixels and has a large file size. 

To use the laser cutter machine, we need to know how to use coreldraw. To vector cut, it is the red color and to engrave, it is the green color which can be customized at the bottom right of the screen. 

Kerf is the amount of material burned away due to the laser's own width displacing some of the design cut out from a piece of material. For instance, if you want to make a tab and slot be fitted closely to each other without any loose, make the tab or the slot 0.01" smaller to its dimension.

With this knowledge learnt, I will apply it to the next practical on laser cutting which requires my group to design a parametric construction kit and laser cut it during the practical.

Standard Operating Procedure in the operation of laser cutter:

·       Procedure

a. Start-up

S/N	Steps/Description	Action
1	Ensure operators know where the fire extinguisher is.	Locate the nearest fire extinguisher
2	Check operators are in proper attire before operation: For neck, remove all collared objects. For hair, long hair is tied and clipped up. Full-covered shoes and long pants are worn.	-
3	Check laser cutting bed has no leftover debris.	If have, fully open the lid to 90°and clean it with a dust broom
4	Gently pull down the lid to close when done.	Check interlock light, ‘L’ and ‘R’ are lighted green.
5	Ensure power switch for pump compressor is turned on. Switch on air compressor from the back located at the side of machine.	Press ‘I’ or ‘II’ on the red switch
6	Switch on fume extractor/exhaust from the back located behind the machine. Wait for 1 minute.	Press the green button
7	Ensure lid is closed.	Check interlock light, ‘L’ and ‘R’ are lighted green
8	Switch on laser cutter machine located in front.	Press ‘I’ on the black switch
9	Wait until the laser cutter machine finishes running the initialization process from the machine panel.	Machine panel shows ‘CO2 Fusion’
10	Place material on laser cutter bed.	Fully open the lid to 90°
11	Gently pull down the lid to close when done.	Check interlock light, ‘L’ and ‘R’ are lighted green
12	Proceed to the workstation to set drawing for the laser cutter machine.	-

 

b. Operation of laser cutter including the basic use of Corel-Draw

S/N	Steps/Description	Action
1	Open Coreldraw app.	-
2	Open the file that is going to be cut out/ engraved.	Click file > import > select design
3	Adjust the size and position of the selected design on Coreldraw.	-
4	Identify parts to cut or engrave. For cutting: Select the parts that are going to be cut out. Change the colour to RED and the width to “Hairline”. Adjust colour settings for RED (R: 255, G: 0, B: 0). For engraving: Select the parts that are going to be engraved. Change the colour to GREEN and fill the whole shape with green. Adjust colour settings for GREEN (R: 0, G: 255, B: 0). To fill, click on the green colour on the bottom left of the screen.	Open the “Outline Pen” tab by double clicking at the bottom of the screen to change colour and width.
5	Send file to Laser cutter	Click the “Print” icon, the 4th icon at the top left of the screen
6	Adjust the position and size of the selected design in Coreldraw by following the ruler	-
7	Set Auto Focus to “ON” (for Epilog M2 Machine) or “THICKNESS” (for Epilog Pro Machine)	Click the button beside or below the word “Auto Focus”
8	For engrave: Adjust speed to 20%, power to 85% and frequency to 85% For vector: Adjust speed to 10%, power to 80% and frequency to 80%	-
9	Measure the thickness of the material using a vernier calibre. Import material setting from the library For cutting: Click into the VECTOR tab and select the material that is being used For engraving: Click into the ENGRAVING tab and select the material that is being used.	Click “Import Material Settings”
10	For both vector and engraving: Set thickness to the thickness of the material being used.	Type in material thickness into the thickness tab
11	Set AIR ASSIST to ON for all processes.	Click button beside “Air Assist” from OFF to ON
12	PRINT out the design	Click on “Print” button
13	Verify if the correct file is sent. Take note of the time needed to cut/engrave material.	Look at the machine panel
14	Start cutting/engraving	Click the green “GO” button on the machine panel
15	When done, leave product in the machine for a minute.	-
16	Open the lid of the laser cutter machine and tap on the cut pieces of the material to remove the cut pieces.	Fully open the lid to 90°

 

c. Shutdown

S/N	Steps/Description	Action
1	Remove all finished pieces and materials. Check that there are no leftover debris and materials. Make sure there is nothing left on the laser cutting bed.	If there are any leftover debris, fully open the lid to 90°and clean it with a dust broom
2	Gently pull down the lid to close when done.	Check interlock light, ‘L’ and ‘R’ are lighted green
3	Switch off laser cutter machine located in front.	Press ‘O’ on the black switch
4	Switch off fume extractor/exhaust from the back located behind the machine.	Press the lighted green button
5	Switch off air compressor from the back located at the side of machine.	Press ‘O’ on the red switch
6	Perform Housekeeping. Do not leave anything on the computer table.	-

Revision	Superseded Version	Revision Details	Effective Date
1	NEW	This is a new document.	01/11/2021
2	Revision 1.0	Start-up was made more detailed and new steps were added (location of fire extinguisher). Operation was made more detailed and new steps were added (adjusting color, speed, power, frequency for vector and engrave in Coreldraw and measuring thickness of material).	15/11/2021

Reflection on improvised SOP: 

The improvised version of the SOP is indicated in red. I have added more details that are specific to the steps and explained more on where we can locate the icons in Coreldraw. Most of the steps in my group's SOP are correct but we needed to add some steps such as measuring the thickness of the material where it will be laser cut on. Some of the settings in Coreldraw are added too so we can navigate and locate things in the app easily. With this improvised SOP, I am confident that I will be able to laser cut my own group's chemical product for our capstone project. This improvised version of the SOP helps me to understand how to use the laser cutter machine and to take note of any safety hazards and reduce errors from occurring in the Coreldraw app.

Laser Cut Product: 

My own laser cut product

My group's construction kit

My group's Christmas Tree

Sketches of our shapes in our construction kit:

Overall reflection during laser cutting practical:

All in all, the laser cutting practical was a fun and fresh experience as it was my first time using the laser cutter machine. I was able to follow the instructions and demonstration given by the lecturers and execute them during my competency test. However, my laser cut product was a bit too small as I didn't adjust the size after clicking on the print icon of CorelDraw. Thus, I need to make sure the size is adjusted accordingly so as to make the product look nicer when it's being laser cut and to also preserve the limited resources we have.

My group and I were able to laser cut our construction kit to form a Christmas tree, our main idea and product during our discussion in tutorial lessons. The Christmas tree would be made up of two parametric designs, the triangular shaped as the leaves and the flower-like shaped to connect the leaves together like the stem of the tree and as a star on top of the tree. These shapes were designed in Fusion360 using parametric design which would be exported as a .DXF file and saved into a thumbdrive to be inserted into the computer in school connected with the laser cutter machine.

During our discussion, we faced some challenges such as forming another product with the two shapes to form a Christmas tree as we were tasked to make a construction kit that could be assembled in multiple designs using the shapes we have design. Because our main product was a Christmas tree, it was difficult for us to come up with new products to be designed using only the two shapes. After thorough discussion and considerations within the group, we decided to add a rectangular shaped with curves at its ends into our construction kit to form a lantern. As we settled into our final shapes we want to design to be laser cut, we were able to come up with more ideas and products that could be assembled using our construction kit.

The challenge we faced at first during laser cutting was adjusting the size of our flower-like shaped parametric design in CorelDraw after clicking the print icon as the size will be reflected on the material. In order to make sure our parametric designs were able to fit into our design of a Christmas tree, we adjusted the boundary in CorelDraw and used the ruler in the laser cutter machine and CorelDraw to gauge the size to be laser cut in the material. To add more designs to be laser cut onto the material, we will select the design and copy and paste it and adjust its size accordingly as well. Another challenge we faced while laser cutting was that we did not focus on the slots of our construction designs as it was our first time. So, when our construction design was being laser cut, the slots of the flower-like shaped was too tight or too loose to fit the triangular shaped. 

Additionally, we learned that by adjusting the sizes in Coreldraw, the slots in our construction design gets adjusted as well. Because of these, it was hard to fit our construction kit together to form a Christmas tree as some slots in the design were too tight or too loose. Initially, we thought that the sizes of the slots that were made the identical to each shapes being designed will be the same as the one when being laser cut. Thus, we learned the importance of kerf and made note to include these in our future projects. Nonetheless, we were satisfied and proud of our construction kit as we were able to form a Christmas tree in the end. These are some of the notes we will take note of when using the laser cutter in our future projects.

References:

‌1. DINFOS Pavilion. (n.d.). Vector vs. Raster Images: Choosing the Right Format. [online] Available at: https://pavilion.dinfos.edu/Article/Article/2223089/vector-vs-raster-images-choosing-the-right-format/. [Accessed 29 October 2021].

2.  Gabriel Elkaim., University of California, Santa Cruz Board of Studies in Computer Engineering,2016 Laser Cutter Standard Operating Procedure [Accessed 27 Oct. 2021].

3. SendCutSend. (2019). What Is Kerf in Laser Cutting? [online] Available at: https://sendcutsend.com/what-is-kerf-in-laser-cutting/#:~:text=During%20the%20process%20of%20laser [Accessed 29 October 2021].

4. www.youtube.com. (n.d.). laser cutter 03 coreldraw. [online] Available at: <https://www.youtube.com/watch?v=VoAswZRCVVQ > [Accessed 27 Oct. 2021].

5. www.youtube.com. (n.d.). laser cutter 04 operation. [online] Available at: <https://www.youtube.com/watch?v=jUUBFNWpuDY > [Accessed 27 Oct. 2021].