Before I started this hobby, “CAD software” sounded like something for engineers, not hobbyists. It isn’t. If you can measure a shelf and drag a mouse, you can design a simple, printable part in an afternoon. Here’s the exact process I use for the parts I actually need around the house.
Step 1: start with a real measurement
Don’t open the software with a blank idea. Start with an object you want to replace or a gap you want to fill, and measure it with calipers or a ruler before you open anything.
Step 2: sketch on a single plane
Every model starts as a 2D sketch on a flat plane. Draw the basic outline of your part using rectangles, circles, and lines — don’t worry about getting it perfect. Most CAD software lets you add exact dimensions afterward.
- Use the rectangle tool for boxy shapes, the circle tool for round ones.
- Add dimensions to each line by clicking it and typing the exact measurement.
- Fully constrain the sketch — most software will turn the lines a different color when every dimension is locked down.
Step 3: extrude it into 3D
Once your sketch is a closed shape, use the “extrude” tool to pull it into three dimensions. For a small bracket, 5–8mm is usually plenty of strength without wasting material.
The extrude step is where a flat sketch becomes an actual object. It’s also the moment CAD stops feeling abstract and starts feeling like building something.
Step 4: round the sharp edges
A small fillet (rounded edge) on outer corners makes parts look more finished and print more cleanly. A 1–2mm fillet is usually enough.
Step 5: export to STL and check it in your slicer
Export your finished model as an .stl file, then open it in your slicer before printing. Check the scale, that it’s sitting flat on the build plate, and that any steep overhangs have supports enabled.
That’s genuinely the whole loop: measure, sketch, extrude, round the edges, export. Every part I’ve designed since has used this same process, just with more steps chained together.
