Give the overall size first
Say the base shape and its sizes before details: "a rectangular plate 120 by 80 mm, 8 mm thick".
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Text to CAD
Write what the part is and how big it is. VIZON turns the text into a parametric CAD model you can edit feature by feature and export as STEP or STL.
How to write a text-to-CAD prompt that builds first time
The AI works in millimetres and in CAD features, so the closer your words are to sizes and features, the better the result.
Name the features
Use words like hole, through hole, counterbore, fillet, chamfer, boss, rib, slot, pattern and shell.
Place things clearly
Say where: "centred", "15 mm from each corner", "on the top face", "around the axis".
Ask for patterns, not copies
"Six M8 holes on a 100 mm bolt circle" builds one hole and a circular pattern, which stays editable.
Change it in small steps
After the first result, ask for one change at a time: "make the boss 5 mm taller".
Prompts written this way
- A round flange, 150 mm diameter and 12 mm thick, with a 60 mm hub 20 mm tall, a 40 mm bore through the centre, and six 10 mm holes on a 120 mm bolt circle.
- An L-shaped mounting bracket, 3 mm thick, 50 mm wide, with legs of 60 and 40 mm, two 5 mm holes in each leg and a 2 mm fillet on the inside bend.
- A box-shaped enclosure 100 by 60 by 40 mm, shelled to 2 mm walls with the top face open.
Text to CAD, step by step
Want more detail? Read the guide: How to Create CAD with AI.
- Open a new CAD part and click AI.
- Write the description, including units and the main features.
- Optionally attach reference images to show the shape.
- Generate, then check the feature list and the model.
- Refine with follow-up requests or by editing features directly.
Made in VIZON
Real models built with these tools. Each one is free to download.
Spur gear20 teeth, module 2, with a raised hub and an 8 mm boreCAD part · free STEP, STL
Electronics enclosure100 x 60 x 40 mm box, 2 mm walls, open top, four M3 screw bossesCAD part · free STEP, STL
Control knob30 mm knob with a 6 mm shaft bore and 12 grip flutesCAD part · free STEP, STL
Finned heatsink60 x 40 mm base with nine 25 mm cooling finsCAD part · free STEP, STLFrequently asked questions
What is text to CAD?
Generating a CAD model from a written description. In VIZON the output is a parametric feature list, so it stays editable like hand-made CAD.
Do I have to specify units?
VIZON CAD works in millimetres. Writing the units in your prompt avoids any ambiguity.
What if the result is not quite right?
Ask for the change in plain words, or open the feature and change the number yourself. Both keep the rest of the part intact.
Related VIZON tools
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