4. Computer-Controlled Cutting
For this week we have two types of assignments, group and individual. For the group assignment, we will characterize the laser cutter in the lab by making test parts of different settings and we will document the group work on fab lab Bahrain website. For the individual assignment, I will design, laser cut, and assemble a parametric 2D press-fit construction kit. In addition, I will cut my vector design from previous week on the vinyl-cutter.
- Laser cutter.
- Vinyl cutter.
This week assignment content:
Final version of this week files:
For images editing and compressing, I used the following:
- Screenpresso to add comments and signs on images.
- If you are using window, press window + G for video recording.
- Online Converter to cut and convert video to gif image.
- GIF compressor to compress GIF.
About the laser cutter:
I just have used the laser cutter for the first time in fab academy 2020 bootcamp, so I am a beginner. The laser cutter works by directing the laser power output to the material want to cut or engrave. There are three types of laser cutters, CO2, crystal, and fiber. Classification of laser cutter based on the laser output. The laser cutter machine we used in the lab is RDWorks and it is CO2 laser cutter type.
- Connect the laser cutter with the exhust pipe to get rid of the generated smoke during cutting and engraving process.
- Don’t leave the laser cutter machine while running, be around and observe it.
4.1. Characterize your lasercutter's focus, power, speed, rate, kerf, and joint clearance.
My group assignement role:
For the laser cutting group assignment, each student chose to work on a task and document the work on the Lab website. Click here to go to this week group assignement page. For me, I chose to work on the joint fitting task using acrylic material.
What I learned from this group assignement:
- Working in a group was fun and enjoyable for all.
- We need to set a plan and layout for the group assignment page.
- We need a group leader who can magnage the work between us.
4.2. Design and laser cut a parametric press-fit construction kit.
For this task, I decided to use Fusion 360 to design my parametric press-fit construction kit. First of all, I have searched about the parametric design concept, uses, and examples. Based on my research, parametric design is basically defining some variables with specific values that can be used anywhere in your design by referring to the variable name. Parametric variables values can be changed during any design phase, which gives the user more design flexability and easier control.
Here you can find some useful parametric tutorials links:
And here you can find some inspiration 2D construction kits:
- Material used: Mat Board.
- Material best fit: 1.05 mm.
- Material area per student: 30 x 20 cm.
My design steps:
1- Set your parametric values from (SOLID > MODIFY > Change Parameters).
2- Add (User Parameters) to your design by setting a Name, Unit, Expression, and comment for each.
3- Create Sketch and select the ground plane face.
4- Create Diameter Circle, set the dimensions you want from the defined parameters, and click on FINISH SKETCH.
5- To create press-fit cuts for your designed sketch, click on (SOLID > Create Sketch > select gournd plane > SKETCH > Line) and draw the line on the edge you want.
6- Press (d), click on the line you want, and set the value as one of the user parameters (for my design I chose Thickness).
7- To set the created lines to the middle of the circle:
- Create (Line) and move the cursor on the middle line until a triangle shape appear to you, then click on this point (this is the first point of your line).
- Place the end line to the middle point of the circle.
- Click on (Constrain) and select the line.
8- Press (t) on the keyboard to trim the outer line.
9- The same design method was followed to design the other shapes. My final design:
10- Export each sketch as .dxf file and open it in inkscape to deplicate my sketches and set the print size.
11- Install RDWorks software.
12- Import your file to RDWorks software.
13- Origin point ((where the laser cutter will start cutting)) is represented by a green dot in one corner of the object.
14- You can set the Origin point from Config(S) > System Settings > chose where you want the Laser head.
15- To set the layer parameter by double click on the layer color or mode from the top right window.
16- There are two main layer paramters, which are speed (mm/s) and power (%). To check parameters library, click on Parameter library and chose the one that meet your needs. Also, you can set these parameters manually. You can change it from the laser machine later.
For cutting, we aim to use the maximum power (approx. 85) to allow us to cut the material with a faster speed setting without the fear of not cutting all the way through. For engraving, we aim to use the maximum speed (approx. 200 mm/s) and very low power to achieve the desired darkness, so it doesn’t cut all the way through material; it just cuts a little way.
17- Click on Download to send the file to the laser cutter machine.
18- Send the print file to the laser cutting machine.
19- The laser machine screen will display the print file and let you set the Speed, MaxPower, X, Y, and Z location. For my design, I set the speed to 71 mm/s and the power to 50 %.
20- Press Frame button to show you the actual print area on the bed.
21- After cuutting, I have assembled the construction kit in multiple ways and got the final shapes as shown in the following images:
4.3. Vinyl cut of a vector design.
For this task, I have used my 2D vector design file from previous week work. The vinylcutter used in our lab is the Electric Silhouette Cameo 2 . This machine width is 12 inches, which means that the printed design file width shouldn't be more than 12 inches. For the print length, it is limited only by the length of the sticker roll (the used one 2 meters approx. ). The following steps were followed to do the task:
- Install the silhouette studio software.
- Plug in and power on the Silhouette machine.
- Connect the Silhouette machine to your laptop using USB cable.
- Import your design file from the top left menu (File > Open > select the file you want to print).
- From the right side tool bar, click on the (Trace) icon, the (Select Trace Area) and draw a rectangle around your object.
- Chose the Trace Preview as (Outline) or (Solid Fill), for my design I chose the second option.
- When you finish tracing, click on (Trace) from the Trace Style down menu.
- From the machine hardware side, change the cutting depth manually from the blade as per the recommended depth in the software for the material used.
- (Load cut mat) to the machine.
- When your file is ready to be printed, send it to the machine by clicking on (Send) from the top right corner, then set the printing parameters as you need. For my design I set the following: Material: Vinyl, Glossy - Action: Cut - Tool: Ratchet Blade - Speed: 5 - Force: 10 - Passes: 1.
- After cutting, unload the material and start weeding the unwanted materials. You can use a tweezer for this purpose.
- Add an Adhesive Vinyl transfer tape on your sticker paper.
- Carefully take off the transfer tape and make sure your design is sticking to it.
- Stick your design on the surface you want to add it to and remove the tape slowly from the surface.
- Finally, you will have your desgined sticker. For me, I have added my design on two surfaces, my laptop and the fab lab door.