Week 3: Computer-Controlled Cutting¶

Weekly Points of Focus¶

2D Operations → Laser Cutter & Vinyl Cutter
Group Assignment → Laser Cutter Characterization
2D Parametric Modeling & 2D Toolpath Generation (Vector-based)
Recitation → Debugging
Documentation Review → Clear process explanation
Final Project Progress Review → In the process of learning, align the practice to the FP too.

Checklist (Self-Assessment)¶

Linked to the group assignment page
XExplained parametric design process with words and images
Documented press-fit kit design and fabrication
Documented vinyl cutting process
Included original design files
Included hero shots of final result

SSTM¶

My delievarables¶

By the end of this week, I will be expected to:
- Demonstrate parametric 2D modeling workflows
- Explain the laser cutting process from setup to execution
- Design and fabricate a press-fit construction kit
- Identify and explain the vinyl cutting workflow
- Document my work clearly with images, explanations, and files

Assignment Overview¶

This week focused on 2D fabrication workflows, specifically laser cutting and vinyl cutting. The goal was to understand both the design side (parametric 2D modeling) and the machine side (characterization, safety, kerf, and workflow), and then apply that knowledge to produce a parametric press-fit construction kit and a vinyl-cut laptop sticker.

Individual Assignments¶

Purpose: - Design, laser cut, and document a parametric press-fit construction kit
- Account for laser kerf in all slot dimensions
- Design and cut a vinyl laptop sticker using vector software

Group Assignment: Laser Cutter Characterization¶

week03 Gr Assignment

What we did as group:

The laser cutter characterization:
- Fix laser cut lens
- What the machine can and cannot do
- How precise it is
- How settings affect cut quality and accuracy

In our incubation center, I have (The following INK equipments are freely available for startup desigated to the center):¶

GS-100-W laser system

Cutter and Plotter¶

C-48LX Contour Cutter Plotter¶

A contour cutter plotter used for precise cutting of printed graphics, stickers, and vinyl by automatically following registration marks. Reads optical marks to accurately contour-cut around printed designs. Ideal for sticker production, labels, decals, and signage vinyl.

C-48LX contour cutter/ploter

Roland GX-24 Vinyl Cutter¶

A precision desktop vinyl cutter used for cutting vector designs from adhesive vinyl and heat-transfer materials. Cuts logos, text, and graphics for decals, signage, and T-shirt transfers.Works directly with vector files from design software like CorelDraw and Illustrator.

RolandG24 vinyl cutter

GS laser system¶

My GS laser system (100 W) is an industrial-grade CO₂ machine that uses a 100-watt laser source to precisely cut, engrave or mark a variety of materials. It’s typically designed for high-accuracy, automated processing of non-metal and some metal workpieces, depending on the model and optical setup. Common features include: - 100 W laser power for efficient cutting/engraving. - CO₂ laser technology (10 600 nm wavelength) for cutting/engraving acrylics, woods, plastics and leather, or fiber laser for metal (engraving) marking depending on variant. - Cooling system (air or water) and built-in safety features for stable long-term operation. - These systems are used in manufacturing, signage, prototyping, craft and industrial workshops for detailed engraving, cutting shapes and marking serial codes or logos

Challenges & Debugging laser cutter (GS Laser System 6090 PU)¶

During inspection the GS Laser System 6090 PU had a damaged lens, causing poor cutting quality and weak laser performance. No cut at P=100%a and S=10MM/S
I diagnosed the issue, purchased a new compatible lens, replaced it, and successfully restored the machine to proper working condition. Damaged lens during startups work with it

Replace with new one New lens with 18mm@63.5mm focal length Mounted at the correct place with the correct orrentation Then cleaned all the 3 mirrors and the focal lens, following maintainance manuals.

Now clearly cut at P= 30% and S= 50mm/s, Like 🎃🎃 New file cutting with new lens ixed

!!SOLVED!! (Takes two days) and continue to work now¶

1. Parametric Press-Fit Construction Kit¶

Reference:
https://fabacademy.org/2019/docs/FabAcademy-Tutorials/week03_computer_controlled_cutting/press_fit.html

Design Concept¶

A press-fit kit is assembled without glue, screws, or fasteners.
The accuracy of the joint depends entirely on:

Measuring the real material thickness
Measuring the real laser kerf
Calculating the theoretical slot width
Performing tolerance testing
Using the best result as a parametric notch

Step 1 — Measure Material Thickness¶

Material: MDF Measured using calipers at multiple points: Average thickness = 2.99 mm

Step 2 — Kerf Measurement (20 × 20 mm Test)¶

A 20 mm square was drawn in Inkscape and cut. After cutting:

Measurement	Value (mm)
Outer piece dimension	19.67 mm
Inner hole dimension	20.14 mm

Kerf Calculation¶

Kerf = (Inner − Outer) ÷ 2 Kerf = (20.14 − 19.67) ÷ 2 Kerf = 0.47 ÷ 2 Kerf = 0.235 mm

Laser kerf = 0.235 mm

20x20 kerf test sample outer 20x20 kerf test sample inner

Step 3 — Calculate Theoretical Slot Width¶

Slot width = Material thickness − Kerf Slot width = 2.99 − 0.235 Slot width = 2.755 mm

This is the center value.

Step 4 — Create 11 Tolerance Test Slots¶

Slots were created around the center value with 0.05 mm increments.

Test #	Slot Width (mm)
1	2.505
2	2.555
3	2.605
4	2.655
5	2.705
6	2.755
7	2.805
8	2.855
9	2.905
10	2.955
11	3.005

Each slot: - Height: 6 mm - without added 45° chamfer (~0.7 mm), it is reccomended from fabacademy (I am working on it and update here ASAP) - 3 mm spacing between slots

11 slot tolerance test

Step 5 — Laser Cut the Slot Test¶

Red hairline stroke
Same settings as final cutting
MDF sheet

laser cutting slots

Step 6 — Physical Press-Fit Testing¶

Each slot was tested manually.

Observation:

Smaller slots → too tight
Larger slots → loose
Best friction fit at: Best fit found at: 2.805 mm

testing slot fit

Step 7 — Parametric Notch Template Using Clones (Inkscape)¶

A layer named Notch_Template was created.

The 2.805 mm notch was placed there
All other slots in the design were created using: Edit → Clone → Create Clone

Step 8 — Final Parts Layout on One Board¶

Rules followed:

3 mm spacing between parts
5 mm margin from board edges
Red hairline cuts
No overlapping paths

Step 9 — Final Press-Fit Assembly¶

All parts were assembled by hand:

No glue
No screws
Pure friction fit

Result¶

Using:

Measured thickness (2.99 mm)
Measured kerf (0.235 mm)
11-slot tolerance testing
Parametric cloning method

2. Vinyl Cutting: Laptop Sticker¶

Design & Toolpath Creation¶

Software: Inkscape
Created vector design
Converted strokes to paths
Exported as SVG I decide to work on the following and find the last thing for vinyl practice to cut stickers