WEEK 3: Computer Controlled Cutting

Assignment

Cut something on the vinyl cutter - design, lasercut, and document a parametric construction kit, accounting for the laser cutter kerf, which can be assembled in multiple ways, and for extra credit include elements that aren't flat.

Laser Cutting Machine

A laser cutting machine is a computer-controlled device that uses a high-powered laser beam to cut, engrave, or mark materials with precision. It works by directing the laser through a lens, which focuses the beam to melt, burn, or vaporize the material. Laser cutters are widely used in manufacturing, prototyping, and digital fabrication due to their ability to cut complex shapes with high accuracy. Common materials for laser cutting include wood, acrylic, MDF, paper, fabric, and metals (with specialized lasers). Key parameters such as power, speed, and kerf adjustment play a crucial role in achieving the desired cut quality.

In our Nellai lab, we are using Sill Laser Cutting Machine. Sill laser cutting machines are high-precision tools used for cutting or engraving materials using a focused laser beam. The term “Sill” may refer to a specific brand or a model, but generally, these machines operate on the principles of laser cutting technology, often used in industries such as automotive, aerospace, construction, electronics, and signage.

Working Principle

A SIL E9060 laser cutting machine uses a focused laser beam to cut through materials by melting or vaporizing them. The laser beam, guided by mirrors and lenses, is directed at the workpiece, causing localized heating and melting or vaporization of the material. Assist gases, like oxygen or nitrogen, may be used to blow away the molten or vaporized material, resulting in a clean cut.

Reference Link

Materials Compatible with Laser Cutting

-> Wood like Plywood, MDF, and solid wood.
-> Acrylic & Plastics.
-> Leather & Fabrics
> -> Paper & Cardboard
-> Glass & Ceramics
-> Rubber

Applications of Laser Cutting Machines

Video Tutorial - Laser Cutter

ONSHAPE

Onshape is a cloud-based CAD (Computer-Aided Design) software used for 3D modeling, product design, and engineering. Unlike traditional CAD programs, Onshape runs entirely in a web browser, allowing real-time collaboration, version control, and access from any device. It is widely used in mechanical design, prototyping, digital fabrication, and education.

Application

Assignment

Individual Assignment

Digital Fabrication - Vinyl Cutting & Parametric Construction Kit

-> 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,

Objective

This assignment focuses on utilizing computer-controlled cutting techniques, specifically through the use of vinyl cutters and laser cutters. The objective is to design and fabricate a parametric construction kit, considering factors such as laser cutter kerf and the ability to assemble the kit in multiple configurations. Additionally, the assignment explores incorporating non-flat elements to enhance the complexity and functionality of the design.

Vinyl Cutting

Vinyl cutting is a precise process that uses a computer-controlled cutter to cut designs, letters, or patterns from sheets of adhesive vinyl or other thin materials. It is commonly used in sign-making, custom decals, t-shirt graphics, and sticker production. The cutter operates by moving a small blade along programmed paths, cutting only the top layer of the vinyl while keeping the backing intact for easy application. Vinyl cutting is widely used in industries such as advertising, fashion, and home decor, offering a cost-effective and efficient method for creating durable and customizable designs.

Vinyl cutting is a subtractive manufacturing process where a computer-controlled blade cuts designs from adhesive vinyl sheets. Below are the key steps involved:

-> Software: Create or import vector-based designs (e.g., SVG, DXF, AI) into vinyl-cutting software (e.g., LaserCut).
-> Vector Paths: Ensure all design elements are closed paths with no gaps for clean cuts.
-> Scaling: Adjust dimensions to match the intended application (e.g., stickers, decals).

-> Material Selection: Choose adhesive vinyl sheets (e.g., permanent, removable, heat-transfer vinyl) based on the application.
-> Loading Vinyl: Place the vinyl sheet onto the cutter's sticky backing mat (if required) or feed it directly into the machine, ensuring proper alignment.

-> Blade Depth and Pressure: Adjust settings based on vinyl thickness (e.g., 0.1-0.5 mm). Test cuts help fine-tune these parameters.
-> Cutting Speed: Slower speeds for intricate designs; faster for simple shapes.

-> Send Design: Upload the file to the cutter via USB or software interface.
-> Cut Execution: The blade follows the vector paths precisely, cutting only the vinyl layer while leaving the backing intact.

-> Remove Excess: Use tweezers or a weeding tool to peel away unwanted vinyl ("negative space"), leaving only the desired design.
-> Transfer Tape: Apply adhesive transfer tape over the design to lift it from the backing for precise placement.

-> Kerf Compensation: Unlike laser cutting, vinyl cutters typically don’t require kerf adjustments due to the thin material and blade precision.
-> Multi-Layer Designs: For layered colors, cut each layer separately, align, and apply sequentially.

Laser Cutting Machine

A CO2 laser cutting machine is a powerful tool used for precise cutting, engraving, and marking of various materials. It operates using a high-energy CO2 laser beam that vaporizes or melts the material to create intricate designs with high accuracy.

Design

The parametric construction kit was designed using Onshape. I defined key parameters such as material thickness, slot depth, and tab length using Onshape’s variable feature. These parameters controlled the geometry of each part, ensuring a tight and adjustable fit, especially accounting for laser kerf. By adjusting a single variable (e.g., material thickness), I could generate new sets of parts suitable for different materials without redrawing the model.

Parametric 2D Design

The design incorporates various features, including Sketch, Extrude, Linear Pattern, and Boolean operations, to ensure flexibility and adaptability. The parametric approach allows for easy modification of dimensions and features.

Step by step design procedure

Dimensions Used to design this sketch

3D View screenshots

2D View

Download Original Design Files

Click on the links below to download the original design files:

Design Preparation

I designed a lamp structure and a hexagon box using Onshape, a cloud-based 3D CAD modeling platform. After completing the designs, I exported the individual parts in both PDF and DXF file formats—commonly used for laser cutting because they preserve precise 2D vector outlines necessary for accurate cutting and engraving.

These files were then imported into the laser cutting software (such as RDWorks or LightBurn), which serves as the interface between the design and the laser cutting machine. This software allows users to define which elements of the design should be cut and which should be engraved. Different colors or layers are used to assign cutting and engraving operations, and it provides the tools to adjust settings like power, speed, number of passes, and focus height.

         Cutting Power:  ~80% (suitable for 3mm MDF) 


         Cutting Speed: ~10-15 mm/s 


         Engraving Power/Speed: ~40% power and 200 mm/s 


         Focus: Calibrated using the focus tool for clean cuts 

Once the setup was verified, I sent the file to the SIL E9060 laser cutter. The MDF sheet was properly placed and secured, and the exhaust system was activated for safety. The machine completed the cutting and engraving tasks without error.

While printing the lamp structure, I encountered some issues. The original lamp design had a thickness of only 0.2 mm, while the MDF sheets available in our lab were 3 mm thick. Additionally, the overall dimensions of the lamp parts were too small, resulting in a very tiny printed object that was not practical for use.

To address this, I redesigned a new object-a hexagon box-with standard and practical dimensions suitable for 3mm MDF. After re-exporting and preparing the new file in the laser cutting software, the hexagon box was successfully printed with clean cuts and proper fitting parts.

This process helped me understand the importance of matching design dimensions with material specifications and using the correct software settings to achieve accurate and clean results.

Hero shots for Hexagon Box

Download Original Design Files

Click on the links below to download the original design files: