Week 3 : CCC

Summary

This week I tried cutting vinyl for the first time. I also designed and cut out a parametric box that will probably be used for my project.

My Vinyl Cut

My Laser Cut

Assignments

Group Assignment

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

Individual Assignments

• Cut something on the vinylcutter.
• Design, lasercut, and document a parametric construction kit, accounting for the lasercutter kerf, which can be assembled in multiple ways, and for extra credit include elements that aren’t flat.

Lasercutter’s Characterization

This part was done in group and is accessible on the group page.

Vinylcutter

As for the Vinyl cutter, I didn’t try anything very useful as it’s a first for me. I decided to customize the desk I use at the FabLab. To do this, I started by making my cut-out in Inkscape :

This time it’s much simpler: all I need to do is define the features to be cut. I need to export the file as dxf, another type of vector file.

On the computer controlling the machine, I’ll just need to import the dxf, and configure the cut by choosing the material and a few pre-configured cutting parameters. Then insert the material and start cutting.

Once the cutout is made, stick a sticky plastic over what you want to transfer. What’s left is the outline of the cut-out, and our decal on a piece of paper, shown below. You need to be very careful when making the transfer.

I then positioned the vinyl, rubbed it well so that the entire surface stuck to the table, and carefully removed the clear plastic.

The result is shown below.

Note:

• “Teille” is my nickname, and yes, I like sharing beers with friends !

Source file

• SVG file Vinyl Cutter

First Test with the “Epilogue FusionPro”

During Thomas’s instruction at FabLabULB, we had the opportunity to learn more about the use of lasercuts available at the FabLab. There are two, each with its own pros and cons:

I started by testing the three operations that can be performed with a lasercut: cutting, line engraving and fill engraving. The first step is to create an SVG file that can then be imported into the control software. I launch Inkscape and start drawing, a rectangle, a triangle, some text… You can do whatever you like, but there are a few important concepts:

• You need to define the contours of the shapes, not just the insides.
• You need to assign a different color to each different operation performed by the lasercut (different speed or power).
• Transform everything into “Path” and don’t keep other vector objects.

When this is done, I get the following result in Inkscape :

Then, depending on the machine, the procedure is different, but in general, I must :

• Import the file into the machine’s control software (SVG import, or SVG “print”).
• Define the various operations according to the different colors assigned in the SVG. That is, define a speed and a power.
• Check that the cooling, air extraction and gas jet systems are operational.
• Check that the cutting frame is fully included in the material being cut.

The result is shown below… This is what will later become the front panel of my HV generator!

Source File

• SVG file Testing Epilogue

Parametric Construction Kit

Idea

I got the idea from Youtuber Kevin Pinguin with one of his videos in which he presents his parametric box concept!

His laser-cut storage box generator is very nice! It lets you specify box dimensions and generates ready-to-cut plans. This has inspired me to design customizable boxes using Autodesk Fusion 360 and then laser-cut them in various sizes. It’s a great way to explore personalized fabrication, parametrisation and unleash creativity!

Since my project concerns the development of a high-voltage generator, I’ll need a box to contain the electronics, which is also what motivated me to start designing a parametric box. I don’t yet know the dimensions of what will be contained in the box, so it’s very practical to have a parametric box.

Design with Fusion 360

This time I decided to use Fusion 360 to try out another CAD software for a change.

The special feature of this design is that all dimensions are parameterized in a file called “Master_Para”. All parts designed afterwards import these parameters. If these are modified in the master file, all other files are updated.

Parameters can be accessed: “modify -> modify parameters”. Parameters must be added manually and bookmarked for import.

When a new part is created, a derivation must be inserted “insert -> insert derivation” to import the dynamic parameters.

Sketches are drawn by imposing distances which are functions of these parameters. Here, for example, we’re looking at the height of the part used to clamp two sides of the box.

The sketches are shown below.

I tested drawing functions such as symmetry and rectangular repetition, notably for the small rectangles on the edges of the box.

To create the parts, I just extruded with the thickness of the cut material as a parameter.

An assembly is made to visualize the result of cutting.

Parametrising the Design

To take parameterization a step further, the following table lists the parameters used for the design.

SVG File

Now that the CAD is complete, I need to generate the SVG files so I can cut out the various parts. To do this, I download a Fusion 360 add-in called Shaper Utilities by Origin.

This allows me to export an SVG file from a surface by simply clicking on it. I’m doing this with my three pieces. Then I create a file containing all the cut-outs. This is shown below:

Note: Shaper Utilities exports a full file when a surface is selected. You just need to modify this by removing the solid and adding an outline so that it can be used by laser cutters.

Cardboard Parts & Result

I now head for the laser cutter. I decide to use the Lasersaur. I import the SVG file into the control software and define the cut based on the machine’s characterization of the material, in this case a particularly strong and beautiful cardboard.

I use 80% of the power and 60% of the speed of the laser cutter to make my cuts.

Below, I show the various stages of the cutting process: the material in the machine, the cut, the separate parts of the frame and assembly.

I made a box measuring 10x10x7cm and another measuring 10x10x1cm to make a lid.

A few comments:

• I’ve carried out several iterations of the design because some distances were set incorrectly.
• I’d like to improve the settings by, for example, setting the number of iterations of the rectangular repeat to have several attachments when the box is larger.
• I’ve had a problem with play, as the cardboard is more deformable, so my final result isn’t as solid as I thought it would be, and as the design suggested. I’ll have to keep testing this.

Improved Version

This was done after week 3.

Parameters modifications

Instead of being free to choose the dimensions of the box, I preferred to standardize everything. This allows me to standardize the assembly afterwards too. The parameters are now as follows:

The sketch design therefore had to change in line with these new parameters. I’ve also set the rectangular repeat function so that when I increase the width factor by 1, for example, the rectangular repeat adds a connector to the design. So there’s one connector per 50mm.

And the overall rendering changes too, as there’s more embedding between the parts.

Making SVG

Here I’ll generate an SVG file in the same way as explained in the previous section. The file will include different “base” sizes and different “side” sizes. This way, I’ll be able to assemble the whole in different ways.

Assembling Boxes

With this set of parts, I can assemble the boxes in different ways, and assemble the boxes together in different ways too. It’s very practical!

Below are a few examples of what I’ve done.

There’s still room for improvement. In fact, my design is not yet completely finished, although the result is already quite satisfactory! For example, I’d like to :

• To be able to put small contents inside large ones, side by side. Thickness has to be taken into account.
• Place containers side by side on top of other containers. Here too, thickness is a factor.

Generally speaking, the assembly of the boxes is complete, but we now need to go a step further and think about the assembly of assemblies.

Source Files

• Cutting SVG
• New Parametrical Boxe