--- title: "CAD and making by machine" description: "Use computer-aided design to define digital geometry, prepare files for a chosen manufacturing process, and review parts against the materials and limits of 3D printing, laser cutting or CNC milling." canonical: https://lightmysky.com/learn/design-and-technology/cad-and-making-by-machine-mt_jNf8g85YbY source: https://lightmysky.com/learn/design-and-technology/cad-and-making-by-machine-mt_jNf8g85YbY.md retrieved: 2026-11-12 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # CAD and making by machine Use computer-aided design to define digital geometry, prepare files for a chosen manufacturing process, and review parts against the materials and limits of 3D printing, laser cutting or CNC milling. Subject: Design & Technology · Area: Designing & Making · Ages 14 to 16 Page: https://lightmysky.com/learn/design-and-technology/cad-and-making-by-machine-mt_jNf8g85YbY ## Ready when they can - Explain that CAD stores editable digital geometry, while paper drawings can also specify exact dimensions - Name three machines that take a digital file and what each is good at, such as 3D printing, laser cutting or CNC milling - Give one constraint of filament 3D printing, such as a wide overhang needing supports, a different orientation or a changed shape - Explain why a part must be reviewed against the chosen making method and describe when a design change may be needed ## Lesson: Draw it so a machine can make it CAD means computer-aided design. It stores editable digital geometry: shapes, dimensions and, in a 3D model, depth. Paper drawings can also specify exact dimensions. For manufacturing, export the geometry and prepare instructions for the chosen process and machine. One CAD file is not a ready-to-run file for every machine. A filament printer builds parts in layers and can suit a complex one-off plastic part. A laser cutter cuts outlines in suitable flat sheet. A CNC mill removes material with a rotating cutter and can shape steel with suitable tools. Choose using the part's requirements, material and available equipment. A filament print starts with a first layer attached to the build surface. Later layers attach to existing printed material or temporary supports. Some overhangs can print without added supports. Short bridges may span gaps when anchored at their ends. A wide overhang may need temporary supports, a different print orientation or a changed shape. Check the planned print before making it. Review the design against the making method. A sheet-cut part must suit the sheet thickness and planned joins. Milling tools must reach the surfaces being cut. A printable shape may need changes for milling, but redesign is not automatic. Change what the process or part requirements call for. *(drawing: Preparation depends on the process, machine and material.)* Use the build-test-improve habit you already know. Choose a method early and check its limits before manufacturing. If the method changes, review the existing design. Revise it where needed and prepare instructions for the new machine. Then make and test the part against its criteria. **Recap.** CAD stores digital geometry. Prepare instructions for the chosen machine, check its limits, and revise where needed before making and testing. *Lesson and assessment material written for this dataset.* ## Practice 8 questions on this page, each with its working shown. ## Needs first - [Drawing a design so someone else can build it](https://lightmysky.com/learn/design-and-technology/drawing-a-design-so-someone-else-can-build-it-mt_8ezErqUhZw) - [Iterative Design and Prototyping](https://lightmysky.com/learn/design-and-technology/iterative-design-and-prototyping-mt_fYD3KaViOZ) ## Opens up - [Making One, Making Thousands](https://lightmysky.com/learn/design-and-technology/making-one-making-thousands-mt_0wbzsY10cQ)