COMPUTER CONTROLLED CUTTING🔩

weekly assignments⚙

Characterize your lasercutter’s focus, power, speed, rate, kerf, joint clearance and types.

FIRST AND FOREMOST, I SET A SOUNDTRACK TO ACCOMPANY MY WORK THROUGHOUT THE PROCESS(23.-"Rubicon" by Peso Pluma IS MY FAVORITE SONG ON THE SOUNDTRACK).

Why is important the computter control cutting?

is essential for its precision, efficiency, and versatility across industries. It enables the fabrication of complex designs, ensures reproducibility, and enhances safety through automation.

WTK!. What the KERF?

The "kerf" in CNC laser cutting refers to the width of the line that is cut when dividing a material with the laser. It's crucial to consider when designing to ensure the accuracy of the final size of the piece.

To address this issue, we conducted cuts on a series of rectangles. We tested it using 3mm MDF and 3mm acrylic. By determining the number of cuts needed, the equation becomes straightforward since we have a set number of internal cuts equivalent to a complete cut. By sliding all the pieces to one side, we created a gap that we can measure using a caliper. This means that the cut can be calculated by dividing the total space by the number of cuts made.

How cut?

The cutter we are using is one:

CFL-CMA1080K:

Area ⏩ 1.00 x 0.80 meters.
Table ⏩ Honeycomb or rod
Accesory ⏩ Double Tube
Cutting speed ⏩ 0–36,000 (min/mm)
Engraving speed ⏩ 0-64000 (min/mm)
Power ⏩ 100 Watts
Cutting thickness: ⏩ 0–25 mm
Cutting thickness: ⏩ 0–25 mm
Resolution ⏩ Up to 4000 DPI (typically between 600 DPI and 2000 DPI)
Motion accuracy ⏩ 0.01 mm

Facts:

When choosing materials for CNC cutting, it's important to consider their compatibility with the machine and the cutting process. Woods, plastics, and metals are typically suitable, while materials like glass and stone may not be. Selecting materials that match the machine's capabilities and cutting tools is crucial for optimal results.


Tool Function
Unfocused Laser Beam ⏩ The initial laser beam generated from the laser source, wider and less concentrated than when directed.
Focus Lens ⏩ Focuses the laser beam into a smaller, more potent point, vital for achieving effective concentration.
Focal Distance ⏩ Determines the location where the laser beam is highly concentrated, essential for aligning the focal point with the material surface.
Laser Nozzle ⏩ Guides the laser beam onto the material and eliminates residues from cutting or engraving.
Focused Laser Beam ⏩ Upon traversing the lens, the beam undergoes further concentration, thereby amplifying its intensity.
Focal Point ⏩ Where the laser beam is at its maximum concentration, resulting in the most significant cutting or engraving impact.
Focus Depth ⏩ Represents the span along the laser beam axis where the light persists within a confined point.

A distance of 5 mm from the nozzle is advised for achieving optimal focus. Occasionally, adjusting the focus below the material surface can manage the cutting shape, particularly with thicker materials.

Materials:

Materials you can cut Cut Engrave
Paper ✅ ✅
Cardboard ✅ ✅
Foaming ✅ ✅
Leather (Natural and synthetic) ✅ ✅
Cork ✅ ✅
MDF (pressed cardboard) ✅ ✅
Wood ✅ ✅
Plastic ✅ ✅
Acrylic ✅ ✅
Metal ❌ ✅
Materials you CAN'T cut ❌ Why not?
❌ PVC (Poly Vinyl Chloride) As it ruin the object it emits chlorine gas.
❌ ABS It tends to melt rather and has a chance of catching on fire and leaving behind melted gooey deposits on the vector cutting grid. Cutting ABS plastic emits hydrogen cyanide, which is unsafe at any concentration.
❌ HDPE/milk bottle plastic It melts. It gets gooey. It catches fire.
❌ PolyStyrene Foam It catches fire quickly, burns rapidly, it melts, and only thin pieces cut
❌ Epoxy Epoxy is an aliphatic resin, strongly cross-linked carbon chains. A CO2 laser can't cut it, and the resulting burned mess creates toxic fumes.
❌ Fiberglass Epoxy is an aliphatic resin, strongly cross-linked carbon chains. A CO2 laser can't cut it, and the resulting burned mess creates toxic fumes ( like cyanide! ).
❌ Foodstuff (meat, cookies, bread) Just don't.

Characterization of Laser Cutting Power and Speed:⚡

To evaluate the power and speed of laser cutters, two graphical tests were implemented that combined both variables.

Power: A range of 10% to 95% of the total laser power (100 watts) was used, following the manufacturer's recommendations. The test started with 10% power and gradually increased in 10% intervals. Speed: Speeds from 15 mm/s to 40 mm/s were evaluated, increasing by 5 mm/s each time.

In this experiment, it's evident that power percentages of 30% or lower failed to cut through the material, with the 10% mark even failing to leave a mark. At 40% power, the laser barely managed to cut at the slowest speed, making it the only successful cut. Other power percentages allowed for material cutting, yet the cleanest cut was achieved at 50% power with a speed of 40 mm/s. It's also notable that slower speeds resulted in more burning, indicating poorer cutting quality.

The second test is more comprehensive, involving a larger matrix to explore a wider range of speeds. Additionally, it incorporates a 10% increase in power and includes speeds ranging from 10 mm/s to 100 mm/s in increments of 10 mm/s. This setup allows for a more thorough examination of the laser's performance across various speeds and power levels.

The results from the second test are more extensive, prompting us to create a table to display the findings. However, it's worth noting that there was an issue with the number of combinations and layers, resulting in the loss of the first row, which contained the combination of a speed of 10 mm/s within the power range of 10% to 50%. Nevertheless, a clear linear pattern between engraving and cutting is evident, indicating a correlation where lower power is needed for cutting, while higher speeds require more power.

LEARNING HOW TO USE IT

I had a class on how to use the CNC machine with my professor Oliver. It wasn't as complicated as it sounded.

first step.

  • Ensure the machine's ventilation remains clear and unobstructed.
  • To activate the machine's fan using the button situated on the lower left side.

    • Second step.

  • Turn on the machine using the red button located on the right side of the machine.
  • The safety stop by turning in the direction indicated on the machine, also located on the right side.

    • Third step.

  • Insert the machine key and turn. The lock is located on the top of the machine on the right.
  • Turn on the laser by pressing the button. The button is located next to the key.

    • Fourth step.

  • Place the material you wish to cut on the worktable, ensuring it is securely fastened and level.
  • Ensure the material is within the maximum dimensions allowed by the laser cutter.

    • Fifth step.

  • Ensure the electronic key is connected to the computer to allow the cutting software to open.
  • the laser cutter control software "Smart Carve" on the computer.
  • the design or drawing you wish to cut, ensuring you pick the uit system used

    • Sixth step

  • To adjust the cutting speed and laser power, select your design, then click a configuration number (you can change the color of the configuration to identify where you apply these specifications).
  • Below the configurations, you'll find the speed and power parameters that you can adjust according to your needs (consult the power table).
  • To apply the modifications, double-click on the checkmark next to the configuration number.

    • Seventh step.

  • the height of the cutting table and its start at the top controls of the machine, use the arrow controls to position the "x" and "y" axes, moving forward, backward, right, and left to align with the corner of your material.
  • adjust the distance between the laser and the material until a sharp focal point is obtained. To modify the "z" axis, press Z/U and then "Z move" and adjust the height to 5mm from the material (a reference material can be used to verify this measurement and ensure the laser is at its maximum power).
  • Ensure the laser is correctly focused to guarantee a precise and clean cut.

    • eighth step.

  • To verify that the total material needed matches the material available, press "Go scale" and the laser will outline the cut to confirm it fits within the material.
  • Once all settings are ready and the safety check is complete, start the cutting process from the software with the "start" button.
  • Monitor the cutting process throughout to ensure it is proceeding correctly.
  • Once the cutting is complete, stop the laser cutter from the software and wait for the laser to completely turn off before removing the material.

    Design of my parametric construction kit in fusion 360:

    first parametrico parametrico

      To start designing my parametric kit I must first choose the plane I wanted to work on, in my case XY

      Then I used the line tool and started taking measurements which were 3.50 cm x 2.5 cm x .3 cm and so on until forming a square since the drawing will be parametric

      I do the same process but now with the shape of a triangle I will give it the measurements of 8.20 cm x 1.8 cm x .3 cm and I will finish the sketch

      Now I do the previous process although now with the shape of a hexagon giving the measurements of 4.90 cm x 2 cm x .3 cm and I give them their respective angles to create the shape of a hexagon.

      To create a different figure I will use the slot function from center to center and give it a measurement of 2.40 cm x 8 cm

      Now I will create a rectangle at the edges with measurements of 1 cm x .3 cm and I will click on the symmetry button, I will select the rectangles and then I will select the line that is automatically generated in the middle and the other rectangle will be generated automatically. I do the same step but now for the ends of the figure.

      Now I will generate a circle and give it a diameter of 8.4 cm and I will also create rectangles so that it can fit one with another of 2 cm x .3 cm

      This is how the design of my pieces turned out.

      Second Parametric Kit

      This time, I will make something smaller. For this idea, I was inspired by my colleague’s work. Angel ivan

      To start, I had to set the parameters to create the shapes. This step will help optimize time later in the process.

      Joint

      I will start by creating a joint. I’ll use the dimensions I set in the parameters and then extrude it.

      Triangle

      Now I will create a triangle using the dimensions defined in my parameters.

      L Parametric

      To create the parametric L, I simply entered the dimensions into the parameters and started designing the sketch, and then extruded the design.

      Cuadrado

      To create the square, I followed the same procedure: I entered the dimensions into the parameters and started designing the sketch, and then extruded the design.

      L 3x2

      I created this slot using the dimensions of the previous L; I added 10 mm and a new circle with the same diameter.

      Linea ranural

      Here, I only created a slot using the dimensions from the L-shaped slots. I simply removed the profile from one side so that they would be straight and linear.

      Ranura

      Creating the slot was very easy. I simply used the slot tool and, with the parameters I added, included the circle and some diameter measurements.

    Parametric construction kit:

    The first step I did was read the “How to Use” section. After doing all that procedure: I was able to turn on the cnc machine and open my file in .DXF format

    • After opening the file in the smartcarve program, I selected which vectors I wanted at a specific power and also gave priority to which vectors would be cut first with the colors.
    • The control panel helps me to be able to give priority to certain specific figures and thus be able to make the machine faster
    • adjust the power so that the green cuts and the red is only recorded

      • When you finish assigning the priority and power colors for each figure, click on the start button to start cutting.

      And it will begin to cut according to the priority, speed and power that I set for each element.

      Parametric kit 2

      This was the result of my second attempt at parametric design, and it wasn’t bad at all. I successfully created a stand and a base to hold my phone. I followed the same steps as before: I imported my files into Smart Cave, set the cutting parameters, including speed and maximum and minimum power levels. Then, I assigned priority to all the pieces (blue color).
      Finally, I instructed the machine to start the cutting process.
      This way, I will be able to assemble the pieces later.
      On the left, a spider-type stand, and on the right, a phone stand.

    Vinyl cutting practice

    • order to start, the file with which I will work must be opened (upper left, open button)

    • Select the desired file to start

    • Once the file is opened in .cst format, select it to move it and modify the original file.

    • Modify the file by putting 4 circles on each side so that it could serve as a guide when sticking the vinyl (right side, tools section, draw circle/ellipse button).

    • I clicked the edit button (top left) so I could select everything, you can also just select everything with the mouse but I wanted to make it more efficient.

    • Since I have 5 colors in the design I made in week 2, I will need to place 5 different vectors of the same design (for that I will use the multiple copy tool, this is found in edit>multiple copy. This tool is useful to be faster and have better symmetry) but these will be incomplete since the vectors that are not of the same color will be removed (do this for all 5 vectors).

    • I will enter the number I need from my vectors (in the Horizontal part it only accepts multiples, you will have to manually remove the excess) and click the OK button to create the copies of these vectors.

    • I clicked on the vector and right click, delete button.

    • Having everything ready, I will start right clicking on the break polyline button to delete what is not the same color of the vector.

    • Taking as a reference the colors of my design

    • Select each vector you did not need (with shift+select) and delete them.

    • Here are the 5 vectors with respect to the corresponding colors

    • Right click and select the complete vector to convert to the polyline

    • after what I did above, right-clicking again will give me a new option called integrate polyline so I can move the vector to any side and all this together

    • move 4 vectors outside the white grid so that only the color of a single piece can be cut in vinyl.

    • use the move option (top middle bar>MOVE button) to make the cut centered and save more material

    • to finish, we use the cutting tool (upper left bar) and if the machine is not configured to be used, configure it, and click OK.

    • we do the same step for the 4 vectors until we have all the colors in vinyl.

    • Having already cut the vinyl, it is time to start gluing part by part according to the color hierarchy of the design.

    • And just cut & paste

    My files