Object-permanence ball box — 3D-printable model preview

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Kids & play Multi-part assembly

Object-permanence ball box

Teach a baby that hidden things still exist

A Montessori toy for babies from about eight months. Drop a ball through the hole in the lid; it disappears, then rolls down the sloping floor and reappears out of the open front. It teaches that things still exist when you can't see them.

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Size: 120 × 120 × 100 mm
Shape: Square
Walls: 2.4 mm
Volume: 291 cm³
Est. weight (PLA): 360 g
Parts to print: 2
Category: Kids & play
Made by: Krypto
Built in: 4 steps

What’s in it

Square, 120 × 120 × 100 mm, with 2.4 mm walls
Two splayed legs that tilt it
1 hole in the lid
Lift-off lid (prints separately)

How to print it

Use a ball 40 mm or larger so it can't be swallowed.

Prints as shown on its floor, no supports. The lid prints as a separate part, top down.

Filament: at most about 360 g of PLA printed solid (roughly $7.21 at $20 per kg); normal infill uses less.

To get the files, open it in the generator and choose File › Download STL (one file per part) or Download 3MF (a 3MF per part, plus a Bambu Studio / Orca Slicer project with every part on its own plate).

Questions

What size is the object-permanence ball box model?

The object-permanence ball box model measures 120 × 120 × 100 mm (width × depth × height). You can change every size in the free SO3D.xyz generator before you download it.

Does it need supports?

No. Use a ball 40 mm or larger so it can't be swallowed. Prints as shown on its floor, no supports. The lid prints as a separate part, top down.

How much filament does it use?

At most about 360 g of PLA (291 cm³ printed solid), roughly $7.21 of filament at $20 per kg. Normal infill uses less.

How many parts does it print as?

2 parts. The download lays each part flat in its best print position: Download STL gives one file per part, Download 3MF gives a 3MF per part plus a Bambu Studio / Orca Slicer project with each part on its own plate.

Can I change it?

Yes. Open it in the SO3D.xyz generator (free, in your browser), change the size, walls, dividers, holes, text or anything else, then download it as STL or 3MF for your slicer.

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Make it fit your space

Change the size, walls, dividers, holes and labels of the object-permanence ball box model in your browser, then download it for your printer. Free, no CAD needed.

Customize this model