week03 | Computer-Controlled Cutting

Have you answered these questions? Linked to the group assignment page. Reflected on your individual page what you learned of your labs safety training Explained how you created your parametric design. Documented how you made your press-fit construction kit. Documented how you made something with the vinyl cutter. Included your original design files. Included hero shots of your results.

Group assignment

After training how to operate the laser cutter

we tested the the effect of speed and power of laser on cutting. We have done our tests on MDF material with 3 mm thickness.

Parametric designed

I started by opening Autodesk Fusion 360.

Before starting the sketch, I saved the project and gave the design file a proper name to keep the work organized.

I began sketching by pressing L (Line tool). Using simple lines, I can create almost any 2D shape.

Sketch the overall shape of the model without worrying about accurate dimensions at this stage:

After finishing the rough sketch, I defined parameters. From the Modify tab, I selected Change Parameters (fx).

I created all the required parameters for the design. During the FabLab training, we used material with a 3 mm thickness, and the measured kerf was 0.19 mm.

Then I returned to the sketch and pressed D (Dimension tool). I applied dimensions using the parameters I had already defined.

I followed the same process for both parts of the model to keep the design consistent.

From the Constraints menu, I selected the Equal constraint and applied it to the dimensions that must stay identical.

After applying all necessary constraints, the sketch became fully defined (all lines turned black).

I defined the slot width using the formula: material_thickness - kerf This formula ensures the parts fit together properly after cutting. | | | |---|---| | | |

Next, I extruded the sketches using material_thickness as the extrusion value to create the 3D model.

To use the model in practice, it needs to be exported in a format compatible with Inkscape:

I selected the correct export size settings to ensure accurate scaling.

I disabled the legend and then clicked Export.

The final file was ready to be opened in Inkscape for laser cutting preparation.

Finally, I also uploaded the original design files in .STL and .F3D formats for documentation and future editing.

Cutting parametric design

Before cutting the final model, I performed a test cut.

In the original design, I used a 3 mm material thickness and 0.19 mm kerf, based on previous cutting tests for focus, power, and speed.

After cutting the test piece and measuring it, I found:

Actual material thickness = 2.91 mm

Slot width = 2.79 mm

So I recalculated the kerf:

Kerf = 2.91 - 2.79 = 0.12 mm

This showed that the real kerf was smaller than the initial estimate.

I went back to Fusion 360 and updated the material thickness, kerf value, and redesigned the tab width accordingly:

Here is the updated sketch after correcting the kerf value.

After adjusting the parameters, the model was ready for laser cutting.

I export the model as a pdf file that is readable for printer. To prepare for cutting, I opened the file connected to the laser cutter and pressed: Ctrl + P → Properties → Advanced (Load Material) I checked the general settings for power and speed, then pressed OK. I placed the HDF material inside the laser cutter and positioned it properly.

Then I started the cutting process.

After the cutting was finished, I removed the pieces carefully from the machine.

Here are the final laser-cut parts assembled from the parametric design. It can be used as a toy for kids, for creativity.

The final result shows that adjusting the kerf value improved the fitting accuracy of the joints.

Vinyl Cutter

Oulu Super FabLab has the vinyl cutter shown below, which is used for cutting thin vinyl sheets to create stickers, decals, and labels:

To prepare the file and cut it using the vinyl cutter, I used Inkscape to create and modify the design. I decided to use the logo of my favorite football club as the model file. After downloading the logo, it needed to be properly prepared for vinyl cutting.

First, I placed the downloaded file in the same directory as my Week 03 assignment files to keep everything organized.

Importing the file into Inkscape

The logo file was imported into Inkscape using the File → Import option.

Since the file was already in SVG format, there was no need to convert it from bitmap to vector, which is usually required for raster images such as JPG or PNG.

Next, the logo needed to be cleaned and prepared for cutting. I started by ungrouping the design. This process was repeated multiple times until there were no remaining grouped objects left in the file:

After ungrouping, I converted all objects into paths by using Object → Object to Path. This step is important because the vinyl cutter can only recognize paths, not shapes or text objects:

Then, I combined all the paths into a single shape using Path → Union, which ensures that the cutter treats the design as one continuous object.

Adding extra elements to the design

Instead of cutting only the logo, I decided to enhance the design by adding a few sticker elements available in Inkscape, such as football icons.

After finalizing the layout and checking that all objects were properly aligned and converted to paths, I saved the file for vinyl cutting.

Vinyl Cutting Process

Now it was time to do some hands-on work by preparing the vinyl material and inserting it into the vinyl cutter. Before cutting the final design, we performed a test cut using a small ball sticker to ensure that the blade depth, pressure, and alignment were correct.

Sending the design to the vinyl cutter

For cutting the complete design, I imported the prepared file into Inkscape on the computer that had the vinyl cutter software installed.

By following the steps below, I sent the design from Inkscape to the vinyl cutter software (CutStudio).

At this stage, I faced the following error:

After searching online, I found that the error occurred because the default page size in the vinyl cutter software was smaller than my design. To fix this, I manually resized the working area to match the size of the vinyl material.

The main logo and one football sticker were transferred correctly to CutStudio. However, the rest of the sticker elements did not transfer properly, so I copied and pasted them manually. This worked, but it is not the correct or recommended workflow, as it may cause scaling or alignment issues.: