Computer Controlled Cutting

This week we had to create something using the vinyl cutter, to test the kerf of a material and create something, both last using the laser cutter.

Vinyl Cutting

For the vinyl cutting assignment, we had to draw anything we wanted and then create the sticker. For this assignment I used Silhouette Studio to make a music note. So, the first step was to create the shape I wanted. I did that using the elipse, the rectangle and the smooth freehand and then merged them all together after selecting them as a one shape using the weld command under modify. The steps I took can be seen through pictures below:

After the design was ready, I had to cut it. But before choosing the material to cut it on, I had to set some settings on the program. Under the cut settings, the only thing I changed was the material to Vinyl. Under the design page settings I changed:

  • Page Size: Portrait
  • Rotate View: 0o
  • Cutting Mat: Portrait
  • Print and Cut Borders: Show Cut Borders
  • So, after the software settings, I was ready to use the machine itself. I chose my material, cut a small piece which was enough for my design, I put it on the sticky mat. After that, I powered on the machine and inserted the mat in the machine using the first top button of the machine (media + cutting mat). That way the mat was inserted properly in the machine. I also made sure that the tip of the knife of the vinyl cutter was adjusted at number 2.

    After my design was successfully cut, I removed the excess material that was around my design by using the special pen and placed adhesive paper on top of it pressing it by using a flat surface(blue material on the picture below). The materials used apart from the material I used to cut my design can be seen in one of the pictures below. The picture with the materials used was taken by one of my colleagues, Dumitru Albot.

    Lastly, after everything is ready, I chose to stick my sticker on one of my important notebooks. Before sticking the sticker to any surface, we have to make sure that surface is clean. So, I removed the back par of the material I used to make the sticker as a result the sticker to be only on the adhesive paper. After that, I stuck it to my notebook and pressed it good by using a card. Lastly, I removed the adhesive paper slowly using circular moves from inside out little by little. And voila!!! My sticker was ready! :)

    Kerf Test

    In order to make the Kerf Test I replicated the test of Daniele Ingrassia that he did on his Fab Academy year on 2015. So, after designing the pieces I would cut to Rhino in one of the Fab Lab's computer using the polyline and line, I was ready to print it. Before I printed it out though, I followed some steps to the program itself and the laser cutter. The material I tested was a 6mm MDF.

  • After finishing my design, I pressed >File >Print.
  • When the pop up windows of the print came, I went to properties and adjusted the horizontal and vertical dimensions of my required laser cutting area.
  • After that, I pressed set in order to set my design in the top left corner of my laser cut area. In order to do that, I dragged the middle point of my cutting area so that my design will be on the top left corner.
  • Finally, I set the speed, power and frequency of the laser cutter for the 6mm MDF to 3%, 100% and 30 respectively and send the job to the laser cutter by pressing print.
  • So, after finishing with the Rhino settings, we procceed to set up the laser cutter. I followed these steps:

  • First I made sure the bed of the machine was clear and clean, chose my material (6mm MDF) and placed it on the bed.
  • Then, I set the jog of the machine by using the cursor provided on the machine to move up and down the options and the joystick to adjust the head of the laser cutter. The jog sets the head of the laser cutter to the point which your laser cutting will begin. To be easier to navigate it on the bed of the machine is helpful to turn on the laser point. After I found my desirable point I pressed down (in the middle) the joystick.
  • After, I set the focus of the machine following the same way and also putting on the head the triangle. The focus moves the bed of the machine. This way we make sure that the settings chosen on the program will be effective. To set the focus properly, the triangle should be in contact with the material you chose to cut. In order to make sure that the focus was set properly, we can go to the jog function and see if the triangle moves. If it does then we can go back to the focus and verify the setting by pressing down the joystick.
  • Finally, after following all these steps, I was ready to cut. So, I moved with the cursor of the machine to job and pressed go and the laser cutting started.
  • So, after laser cutting, I was ready to compute the kerf. The kerf can be computed by [the initial area (-)the final area] / (the lines cut).

    More specifically by using the pictures we could compute the kerf by saying (B-A) / 6. So in my case, my initial area was 25cm and my final one was 24.9cm. So by following the above equation, the kerf for MDF 6mm is about 0.017cm.

    But the laser cutter was not cutting as well as it was supposed to, so one of the Fab Lab's workers realigned the mirrors so now it cuts very good. As a result the kerf was not correct so I had to do it again in order for my press kit to be cut successfully. This time I used another type of test in order to find the kerf and I used Draftsight instead. But again for cutting to the laser cutter I inserted my design to Rhino and followed the exact same steps as before with the same settings.

    After finding the best fit, the kerf in this case would be calculated as follows: (2.055-1.992)cm / 2 . This gave me a value of kerf for the MDF 6mm of 0.315cm. You can visualize it in the image below:

    Another way to make the kerf design is to use parametric design/functions. Parametric is a term used to describe a dimension's ability to change the shape of model geometry as soon as the dimension value is modified. So, to do that I used Fusion 360.

    I started up with drawing a line, and then I went under modify and clicked on "Change Parameters". This function allows me to save dimensions and give a name to them. So, next time I draw a line, I can instead of the dimension to write directly the name of the dimension I saved.

    Apart from the saved dimensions, I could also relate the lines between them by setting them up as parallel or perpendicular in relation with each other. After setting up all these parameters, when I changed the dimensions saved all the other ones drawn according to this one, changed simultaneously.

    After the sketch is over, I right-clicked on the sketch and selected "save as DXF" and the sketch was ready to be laser cut.

    Press Kit

    So, in order to do the press kit, I tried to use Adobe Illustrator free trial. I made the press kit twice because the first time was a fail as I calculated it with the old kerf. Also, I found Adobe a bit difficult to handle, so on my second trial I used Draftsight instead.

    So, I decided to make a lamp. I wanted my lamp to have a tree cut in its two of the four middle sections. As a result, I started making the inside cut first. For the tree, I basically used the curvature tool and the line segment functions of the Adobe Illustrator. An important thing to have in consideration is to draw on a 0.01pt line as anything thicker than this line, the program will recognise it as an engraving. For the main trench of the tree, the branches, the leaves and the roots I used the curvature tool. I used the line segment for the horizontal lines that connect the main trench with the roots. For the leaves what I did was to make one and then copy paste it to the other places. Some of them I rotated them by using thr right click of my mouse and then selecting rotate.

    The tools I used can be seen on the left toolbar. The two arrows are used for selecting and moving. I was using the first one to select the object I wanted and the second one to move it.

    So, after the inner cut was ready I procceded making the box that the kerf I calculated by my first results. To make the rest of the design, I used the rectangle tool, the circle tool and of course the line. When you use the line all I had to do was press my starting point and then a pop up window would come up where I could set the angle and the distance of my line from the starting point. That is a function where I could use with every tool I was using. I also used the text function in order to write on the box so that I could make the engravings. After I made the different parts of the box, I selected each face of the lamp and grouped it together so that it is like one body by pressing CTL and G. When I wanted to edit something within the group all I had to do is select the group and undo the group function by pressing CTL+Shift+G.

    So, the result of this after the laser cutting looked like the pictures below. You can see that as the kerf was not calculated with the current settings of the laser cutter, I had to use hot glue in order for it to stay together.

    So, as mentioned before I tried to make a second trial with the press kit using Draftsight this time. This time what I did was to import the tree design from Adobe Illustrator and then designing on top of it. I exported the tree design as a .dwg file so that I would be able to open it with Draftsight.

    Before using Draftsight, I made sure that I had set the right units as it usually uses inches. To do that, I had to select Tools and then properties and then at the pop up window I had to follow the following:

    After I chose the unit system, I opened the tree design that I made in Adobe Illustrator and saved it as a .dwg file. So, after I opened the file, I started designing the lamp I wanted on top of the current design. To do that, I used the text in order to do the writings, the circle in order to do the circle cut in the bottom and the little circles on two of the four sides of the lamp. Furthermore, I used the polyline in order to do the outline of the box faces. The only mistake that my design has lays on the bottom layer where I had to take into consideration the 6mm margin of the 6mm MDF that I used. Otherwise, with the current kerf calculated was fitting perfectly fine. So after corrections, my final result looked like this:

    Then, I imported the .dwg file on Rhino as I did before with the kerf test design. This time, the approach was a bit different than the one with the kerf. After the import of the file to the program, I had to join the lines of the box faces' outline by using the command join after I selected the lines. If done successfully, it has to say that the lines are joined into one closed curve/line. After that done, I set different colours for the engravings and for the cuts. For the engravings I set red while for the cut I set the colour yellow. So after the different colours were set, I went to File and selected print. Then when the pop up window of the print appeared, I followed the same procedure I followed for the kerf test, but this time in the properties instead of the general I used the color mapping. When I pressed the colour mapping, I made sure first of to select the colour mapping so that I will be able to edit it. After that, I set the settings for the engravings making sure that I deselected the vector and the settings for the cut making sure that I deselected the vector option.

    So after setting everything correctly, it was time to use the laser cutter. I followed the same procedure as above when I did the kerf test. Something I forgot to mention above is that our laser cutter is the Epilog Laser Fusion. Finally. the result looks like this:


    The files for the kerf test and the press kit are attached as a .dwg file. The file for the silhouette is attached as a .studio3 file. The files are listed below:

    First kerf test

    Second kerf test

    Press kit

    Musical Note_Vinyl Cutter