Flat Refillable Ice Pack | Slim Cooling Block

BONBON Capsule Cooling Surprise | Mini Ice Pack + Real Reward Concept

A slim reusable refillable ice pack concept designed for cooler bags, lunch boxes, camping, travel, outdoor family use, and simple DIY summer cooling setups.

BONBON contest concept:
This entry is designed as a capsule surprise idea with two versions:

- a mini capsule-size version that fits inside the BONBON capsule as the surprise item
- a larger real-size version that can be used as a practical reusable ice pack

The mini version represents the small capsule surprise, while the larger version shows the real functional cooling product that the surprise can unlock, represent, or be redeemed for.

Important Capsule Fit Note:
This model is designed for the BONBON 2.7-inch capsule contest. 
https://makerworld.com/uk/models/2566374-bonbon-2-7-inch-capsule-content-checker 
The capsule checker shown in the photos was taken from the contest host/creator’s MakerWorld profile and used to test the model size.
The model was checked inside the official contest-size checker to confirm the fit.

Fill it partly with water, leave enough empty space for ice expansion, freeze it, and use it as a flat cooling block.

The slim rounded shape makes it easy to place inside a cooler bag, lunch bag, backpack pocket, or near small DIY cooling setups where a flatter ice pack is more convenient than a bulky block.

This design uses a recessed filling area and a separate cap, helping keep the overall shape compact and easy to handle.

The ice pack uses an internal honeycomb-style structure to help divide the water volume into smaller sections and support the flat walls during freezing. This helps reduce deformation and stress from ice expansion while keeping the model slim and lightweight.

Important:
Do not fill completely. Water expands when frozen. Always leave empty space inside before freezing.

The internal structure does not mean the model can be filled completely. It only helps support the shape and divide the water volume.

This is a 3D printed container, so always test for leaks before using it near electronics, food, bags, or temperature-sensitive items.

For best results, print slowly and make sure the cap and filling area are printed cleanly before use.

Recommended print settings:

PETG or PLA Tough Plus recommended
0.2 mm layer height
4 walls recommended for freezer use
25–40% infill
5–6 top/bottom layers
Use a clean build plate

Make sure the cap and filling area are printed cleanly before use
Leak test before freezing or daily use

Use ideas:

Cooler bags
Lunch bags
Camping
Travel
Outdoor summer use
Picnics
Road trips
DIY fan cooling setups
Small cooling box setups

Safety note:
This is a 3D printed functional prototype, not a certified food-contact or medical cooling product. Do not use it directly with unpackaged food. Always test carefully before real use.

More of my print-in-place designs: 👇