Make Your Models Adjustable

Ever printed something and wished it was just slightly bigger? Or wanted to put a different name on a keychain without asking for a whole new design?

That's what parameters are for. They turn a static 3D model into a customizable tool.

Instead of getting one fixed shape, you get a set of controls — sliders, text boxes, switches, color pickers — that let you tweak the design in real-time.

This also means you don't need to spend another generation every time you want a small change. Resize, relabel, recolor, or reconfigure your model as many times as you want, all without using up a single extra credit.

The Cheat Sheet

You don't need to learn code to get these controls. You just need to use the right words when you talk to GrandpaCAD.

Slider — number

For anything you measure: dimensions, thicknesses, counts. Min, max, and step are picked automatically based on what you ask for.

"Make a cube with a width number parameter from 10 to 100mm."

Short text — text

One line. Perfect for name tags, signs, engravings, personalized gifts.

"Add a name text parameter for the engraving."

Long text — textarea

Multiple lines. Use this when you want a paragraph engraved on the back of a sign, a gift dedication, or a multi-line label.

"Add a dedication textarea parameter for the back."

Toggle — checkbox

For optional features. Hole or no hole? Lid or no lid? Magnets or no magnets?

"Add an include-lid checkbox."

Dropdown — select

When the answer is one of a few specific choices: round vs. square, M3 vs. M4 vs. M5, EU vs. US.

"Make the shape a select with options Cube, Sphere, Cylinder."

Single color — color

One color you can change without regenerating. Useful when you want to preview different filament colors before printing.

"Add a body color parameter."

Color palette — colors

A fixed-length set of colors — one per region, segment, or layer. The model decides how many slots; you only get to pick the colors.

"Make a five-stripe flag with a colors palette parameter."

Section heading — group

Not a control on its own — just a label that splits a long parameter list into tidy sections like "Dimensions" or "Style".

"Put size settings under a Dimensions group and decoration under Style."

Try It Yourself

Here is a live demo of what these controls look like inside the app. Go ahead, mess around with them!

How to Ask

It really is as simple as chatting. You can combine these in one go.

"Hey Grandpa, make me a storage box. Give me length, width, and height number parameters so I can resize it. Add a label text parameter on the side, a color parameter for the body, and an include-lid checkbox."

GrandpaCAD will pick up on those keywords and build the controls for you automatically.

Pro Tip: Keep it Organized

If you are making something complex with lots of settings, you can ask to group them.

"Put the size settings in a Dimensions group and the decoration settings in a Style group."

This keeps your control panel nice and tidy. Give it a try on your next idea!