Practical 1: Laser cutting

⛄Welcome to my blog❤ 

This week we went for our first lab session based on Laser Cutting at FabLab. 

Objective: To Cut and Assemble Our Designed Shape 

This Practical will help us to understand the procedures of using a laser cutter, at the end of the practical, I should be able to： 

1. Operate the laser cutter and cut the test piece. 

2. Work in a group to cut the first version of our design. 

3. Make adjustments and ready for mass production. 

4. Be more familiar with the laser cutter machine.

 

Pre-Pract

1. SOP

Purpose	To obtain a bowl made by slotting different shapes which will be cut by a laser cutter.
Scope	Ensure safety and follow the instructions based on this procedure.
Responsibilities	LEADER: Kalyani -make sure the team is on the right track and does not side track to something else -supervise the team when in need of help. LASER CUTTER OPERATOR: Madelaine -operates the laser cutter properly. DESIGNER: Jolyn -designs the objects the team wants to cut using the laser cutter. TIMEKEEPER: Cui Han -keep track of the time and make sure the team does not go over the time limit given.
Definitions	NA
Safety	Do ensure that there is nothing hanging from your body (such as lanyard) due to it being tangled into the machine Students with long hair make sure it is properly tied up When opening the cover of the laser cutting machine. Ensure it is open all the way and not partially. When closing the cover of the laser cutting machine, do NOT slam the cover. Once close, check if the safety interlock panel has 2 green LED lights up before proceeding. If both green LEDs did not light up, open the cover and close it again. When operating the laser cutting machine, do not lean your body into the machine and avoid inserting your head and hand into it. After cutting is done, wait for 1 minute before lifting the cover, due to the machine being hot and there will be gases present, hence this 1 minute is to give it some time to exhaust the gases. Ensure to wear thermal gloves when removing the product from the machine.
Materials	5mm Wood
Equipment	Air compressor Fume extractor Laser cutter Computer(CorelDraw, epilogue)
Operating procedures	START-UP Switch on the PC at the workstation. Switch on the air compressor at the back of the laser cutting machine. Switch on the fume extractor. Switch on the laser cutter by turning the key from ‘I’ to ‘O’ and wait until initialization is done and the panel shows “CO2 Fusion”. Once the initialization is done, proceed to the workstation to operate Coreldraw. OPERATION Observe that the 2 green LEDs on the safety interlock panel light up. At the workstation, turn on the Coreldraw software and insert your drive. Export the drawing from Fusion360 to CorelDraw by converting it into DXF format. To export it, select ‘File’, then click ‘Export’, proceed to select the file you wish to export. Once your design is shown on the Coreldraw software, select your line colour, fill and line weight for your design.  Select the area you wish to cut, and click the bottom right icon, adjust the colour so that RED is 255, while GREEN & BLUE is 0. If you wish to engrave, adjust GREEN as 255 while RED & BLUE is 0. Once you have completed your design on the Coreldraw software, click on the file to then print your design using the laser cutting machine. After you have clicked the print icon, your design will then be transferred to another software called EPILOGUE drawboard. Import your selected material by loading into the material library. For our construction kit, we selected “Wood 5mm”. Notify the person-in-charge before printing the product.  Manually turn ON ‘Auto Focus’ by setting it to thickness. Ensure the process type is set to vector and is set to 18%/80%/20% . Name the design “Kaya 7” . Place the wood on the top left side of the laser cutter. Align it along the border of the metal mesh. Close the cover gently once your material has been properly laid. Using the software at the workstation, move your design to the desired position on your material. Check with the person-in-charge about the jog feature. Once the checks are done. Process to click on Print>(M2), check the file name and then click on GO/Play on the laser cutter screen to proceed to laser cut our product. If the laser does not cut through the wood after multiple attempts, check that the lens of the equipment is clean as it affects the quality of the cutting. After cutting the wood, do allow some time, about 30 seconds to a minute to allow the fume extractor to extract fumes from the cut wood before opening the cover. To check if the parts are properly cut, wiggle the pieces in the cutter before completely removing it from the cutter. SHUT DOWN Once you are done using the laser cutting machine, switch off the laser cutting machine by turning the key back from ‘O’ to ‘I’. Wait for the screen panel to go black and when you no longer hear a rumbling noise, the machine is completely off. Proceed to switch the fume extractor off followed by the air compressor. Finally ensure the cover of the laser cutting machine is open before leaving. Perform housekeeping by cleaning up the table as well as keeping the remaining wood at the specific workstation.

2. Design

At the first, we were thinking of making a 🎄Christmas tree by designing a star and different triangles. However, the supervisor told us that it will be difficult to assemble everything together. So we decided to design 2 simple but useful shapes (Fig.1).

Figure 1

Practical

1. Competency test

It is an individual test to help all of us to understand how to operate and cut using a laser cutter correctly.

2. Our first try (Fig.2)

Figure 2

So we tried to assemble these 2 wood pieces, then we realized that they cannot fit nicely as it is too loose due to the Kerf effect. Thus we use the "change parameter" to decrease the width of 1 design by 0.1cm. It works so we mass produce the wood pieces, but we accidentally made too many pieces and it took 16 mins👀 to cut everything (Fig. 3 and 4).

Figure 3

Figure 4

The final product we get (Fig. 5):

Figure 5

During a Group Meeting:

Figure 6

Reflection

This practice is very useful especially the competency test as most of the time we divided ourselves to work on different parts so it is often to us that we might not that clear on one another's job, but the competency test has helped all of us to operate the laser cutter successfully and this reduced the time taking for us to complete everything because all of us understood what to do the next.