3. Computer Controlled Cutting¶
Group Project¶
This week’s group project task was to “characterize our lasercutter’s focus, power, speed, rate, kerf, joint clearance and types”. I was selected to be in a group with Collin Kanofski and Kabir Nawaz, with whom the assinment was distributed fairly evenly. My contribution was characterizing joint types by laser cutting and evaluating different types of joints. The documentation for my group can be found here.
Vinyl Cutting¶
We were assigned to “cut something on the vinylcutter”, but at the Charlotte Latin Lab, there is wall where Fab Academy students put their vinyl cut “stickers”, so we are required to make something unique, preferably with multiple colors. My fellow classmates Collin Kanofski and Connor Cruz were going to both create Among Us characters, and so I continued the pattern. I began by finding a simple image online, but that included mulitple colors, so I chose the one below.
As I had forgotten the process to create a design from an image that can be sent to the vinyl cutter, I first messed around in Gimp and Inkscape, but to no avail. Below is the bitmap I created in Inkscape. Looking back, I do not remember what the problem with this one was and why I did not use it, other than it have an extra line for all the lines.
Although I was able to trace a bitmap in Inkscape, it would not outline the correct lines no matter what the settings were. That is when I tried to polarize the colors of the image in Gimp using the knowledge I had acquired in Week 2: Computer Aided Design. I then put it into Inkscape, but still would not outline correctly.
Collin Kanofsky reminded me that you could trace the bitmap of an image directly in Silhouette Studios, so I began to mess around with that. I first downloaded Silhouette Studios online.
I then put the image in Silhouette Studios.
After playing around with the bitmap settings (navigate to this by selecting the icon circled in the image above), I had a traced bitmap which only discluded two lines that I drew in at the bottom of the design. Landon Broadwell had measured the area we had on the window and informed us that we each had about 3.5-3.8 inches of width for our designs, so I defined the width of the design in Silhouette Studios accordingly, along with calculating the proportional height.
I clicked “Send” at the top right, kept the preset settings (Blade Depth=1, Force=10, Speed=5), and was ready to print.
I grabbed a cutting mat and the vinyl in the five colors I wanted (red, blue, grey, white, and black). I stuck a piece of red vinyl on the mat, and cut.
I then had to weed this, which means taking out all the parts I do not want red (or whatever color the vinyl is) as shown below. I did this by picking at the undesired pieces with tweezers, and, per Dr. Gershenfeld’s suggestion, prying them off along the axis of the design (i.e. not peeling up but along). Of course, after I arrived at what is shown below, I had to remove all of the background red as well. I now just had to replicate this process of cutting and weeding with the other four colors, of which I next cut grey.
Finally, once I had all of these, I used transfer tape to put them all together, by getting each of the pieces with their respective colors to stick to the transfer tape in the desired position. This was made easy by the fact that the transfer tape was transparent, so you can see where you are each part.
All that was left was to put the transfer tape on the wall, press on it with a squeegee so it stuck to the wall, and peel off the transfer tape to reveal the final product.
Construction Kit¶
Designing¶
To create a construction kit, I decided to create an assorment of shapes with simple joints that can be assembled in multiple ways. I used Fusion360 to create this kit, utilizing constraints and parameters while in a 2D sketch. The first sketch I created was to be a circular piece. I started by just creating a circle, centered on one of the axes. I then created a construction line tangent to the cirlce at the top, perpendicular to the axis. I went down the axis some into the circle, created a line perpendicular to the axis, and gave it a fairly arbitrary value at first (I later realized I had to make this line half of the width of cardboard). This first line is labeled 1 in the picture. Then I drew a line perpendicular to the previous one into the construction line (2). Finally, I used the Chamfer tool to create a .04 in chamfer between the construction line and tbe last line (3).
I mirrored these three lines over the axis (I had to make a construction line along the axis).
Next, I just selected all of these, selected Modify>Circular Pattern, used the center of the circle as the center point, and decided on 8 total joints for the circle.
I began to create a rectangle using practically the same process, but Evan Park reminded me that we needed to include parameters in these. To create a parameters, I just used the search tool (s hotkey), searched for parameters, and the screen below would show up, on which you select the +, name your parameter, and give it a value.
To apply this parameter, when giving the value for a line or dimensions or any other measurement in the sketch, type the name of your parameter and select it instead of typing the value as displayed below. If everything in a continuous sketch is properly constrained with parameters and constraints, if you change the value of a constraint so as to scale up or down the size of the object, everything else will change accordingly (e.g. changing the radius of a circle but having the joints all stay with the same dimensions and stay in proportionally the right place on the circle). I created a parameter for the circle’s diameter, the width of the joints, the depth of the joints, and the chamfer value. I created a rectangle with joints using basically the same process, just instead of having to create a tangent construction line, I just used the line of the recetangle. Also, I just created two joints on adjacent lines and mirrored them both over the center lines, as a circular pattern would not have worked with this shape.
Next, I created the hexagon. To do this, I started off with just a 30/60/90 triangle.
I created a half of the chamfered joint with dimensions (I only added all the right parameters in later), and mirrored it to create an equilateral triangle with a joint at the top. I then used the circular pattern again, this time with a value of 6, and using the bottom tip of the triangle as the center point. This created the hexagon below.
I created a square next using the same idea, drawing the square, creating the joint from the middle of one of the lines, and using the circular pattern to mirror it on all the sides.
The last shape I created was a triangle, using the same idea. Here is an image of all of the shapes together.
Cutting¶
To cut the design, I exported it as a .dxf from Fusion360. I uploaded it to the Charlotte Latin EngProj drive under my folder. I could then download it on the computer next to the laser cutter and import it into CorelDRAW, but it would only show a 1D line. After a few more attepmts, Richard Shan showed me that when you import it into CorelDRAW, there is an “view” option which I had to select “top” on because that was the view in Fusion360 where the entirety of design is visible. However, I initially neglected to scale the size of the material up in the settings, leading to the cut not running. To change this, I changed the circled dimensions in the image below to the dimensions of the cardboard I was cutting.
I scaled the design down in CorelDRAW so it would use less cardboard and take less space. I cut it, and was in the middle of a second cut for more pieces when I realized that scaling the design down meant that the width of the joints was too small to fit the width of cardboard, meaning the joints were defective. I scaled the joints back up to the appropiate size with the correct proportions, and cut using the settings on the sheet on the printer.
Finally, I copied, pasted, and cut the small triangle and rectangle a few more times where they could fit on the cardboard.
Assembly Possibilities¶
There are multiple ways in which this kit can be assembled, it is all up to the creativity of the user. However, I displayed below a few of those ways that utilize all the available pieces.
Recreating the Shapes with Working Parameters¶
Because of a few dimensions in the each shape which lacked the proper parameters, making it so that one can not change, for example, the side length of the square without messing the shape up, I went back and made most of the shapes work correctly with parameters. It took a while, but I remade all the shapes so that you could change dimensions for them (side lengths, radii, etc.) and still have a functional joint with the same shape, making everything fully parametric. Obviously, the image below which shows this recreation does not display all the changes I made, but you can see the difference in my file downloads at the bottom of the page.
Week Reflection¶
This week was much easier than the last one, but it still had its challenges. I believe that I would be able to replicate the processes involved in the assignments this week in up to ten times as fast, simply due to the knowledge I gained. Because I had used many of the machines and softwares we used this week, a lot of that knowledge was just reminders, but nevertheless necessary ones. I am now much more confident in my ability usning Silhouette Studios, Inkscape, CorelDRAW, both laser cutters, and the vinyl cutter.
Files¶
You can find the file downloads for all my files for this week here.