Week 13

Assignment requirements

1) Introduction

New concepts gaps

• New topics and concepts 😶‍🌫️😶‍🌫️😶‍🌫️
• How will I survive this Fab Lab Academy 😯😯😯
• It likes 👨🏻‍🍳👨🏻‍🍳👨🏻‍🍳 at the lab
• More the 13 weeks 🫨🫨🫨
• Molding & casting techniques are like cooking & serving 🍳🍪🍳🍪

2) Group assignment - Compare printing & milling molding techniques

For more details visit Fab Lab Peru Week 13 Group assignment

Reviewing materials and security protocols

Reviewing materials

Preparing the workspace

Selecting materials

Selecting materials and molds for each project

Fab Lab Academy supervision and recommendations

3D Printing molds

3D Printing molds

3D Printing molds

Food for minions 🤣🤣🤣🤣

Working with acrilic resin

Working with acrilic resin and silicone

Observing flexible silicone

Molds with different procedures

Mixing the materials

Reviewing the mix

Adjusting the formulation

Adjusting the formulation

Temperature controls

Temperature controls

Molding process

Different project overview

Different projects & molding processes

Working with glycerine

Working different projects at the same time

Working different projects at the same time

Final products

At the end

Video demonstration

4) Individual assigment

Emphasis on the design and colors

We review different proposals

Draw a circle with 45 mmm diameter and create an sphere

Draw a spline and create the handle. Create a volumen with pipeline tool. Extrude the handle superior part

Select the volume and use the joint boolean operation

Fillet option in the handle

Piece with fillet option

Cavity design with 6 mm hole for mold ajusting

Desing the coulping

Completing the piece base

Extruding the mold walls

Case overview

Case overview

Slicing with the Bambu Lab Studio

Preview and export the file

3D printing mold piece 1

3D printing mold piece 2

3D printing mold piece 2

3D printing the product "huaco" base

3D printing the product "huaco" handle

3D printing the product "huaco"

Mold and the product

End of this day

End of this day, but with not enough materials

A lot of products at the homecenter

Primer, a lot of primers

Primer for plastics

Finally, general purpose primer

3D Printer piece with primer base to cover 3D FDM lines

3D Printer piece with primer

3D Printer piece with primer

Finishing with wet sandpaper number 360

Finishing with wet sandpaper number 1000

Constructing the mold

Constructing the mold

Constructing the mold

Mold with packing tape and the piece

Mold with packing tape and release agent. Silicone mix 100 gram of silicone with 2% of catalyst

Not enough silicone. We continued the next day

Not enough silicone. We continued the next day

Not enough silicone. We continued the next day

Reviewing material outside the mold

Completing the silicone and adding guides

Completing the part 1

Completing the part 1 and part 2

Completing the part 1 and part 2

Closing the mold

Silicone mold - two parts

Closing the mold with masking tape

Hole in the mold

Epoxy resin - 1 cup

Catalyst - 1/5 cup - 20%

Mixing Epoxy resin and Catalyst 1.2 cups

Filling the mold

Filling the mold

Review the mix in the mold

Review the mix in the mold

Reducing air bubbles in the mix

Product before sanding

Base with light

Final product presentation

Video demonstration

4) Additional individual assigment

Comments

- More details about materials

- Add usage, hazard, safety information

- Compare materials

Safety protocols

Hazards, PPE used & disposal

Epoxy resin — high attention required

Uncured epoxy is a skin sensitizer — repeated exposure without protection can cause a permanent allergic reaction that worsens with future exposure. Always use nitrile gloves (not latex, which is permeable to epoxy). Eye protection is mandatory. The curing reaction is exothermic — if the cup becomes very hot, thin the pour or work in smaller batches. Work in a ventilated space or use an organic vapor respirator. Never dispose of uncured resin down the drain — allow it to cure fully in the container before placing in solid waste.

Silicone + catalyst - check compatibility first

The tin-based catalyst used at 2% can irritate skin and eyes on direct contact — gloves and eye protection are required. More critically: verify silicone type before combining with plasticine or other materials. Sulfur-containing materials (including some plasticines and natural latex) inhibit platinum-cure silicones, leaving the surface permanently sticky. This project uses tin-cure (condensation) silicone, which is not affected. If switching to platinum silicone, re-test all tooling materials for compatibility.

Aerosol primer - flammable & VOC risk

Aerosol primers are flammable pressurized containers and release volatile organic compounds (VOCs) during application. Apply exclusively outdoors or under strong mechanical ventilation — a standard dust mask is not sufficient. Use a respirator rated for organic vapors. Keep away from open flames, sparks, and heat sources. Do not spray near eyes. After use, fully empty the can before disposal — do not puncture or incinerate even if it appears empty.

Glycerine — burn risk from heat

Hot glycerine (60–70°C) causes serious contact burns. Use heat-resistant gloves when handling and pouring. Use a thermometer — do not estimate temperature by touch. Do not overheat: above ~180°C glycerine decomposes and releases acrolein, a toxic and irritating vapor. If overheating occurs, move away from fumes immediately and ventilate the area. Work near an open window or under extraction.

Plasticine — low risk, one key check

Plasticine is generally non-toxic and requires minimal PPE. Wash hands after prolonged handling. The single critical consideration is sulfur content and silicone compatibility — described above. Keep away from food preparation surfaces. Some plasticine pigments (especially reds and yellows) may cause mild skin irritation on extended contact. Reusable indefinitely — no disposal concern.

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First aid reference

- Skin contact (resin/catalyst/primer): Wash immediately with soap and water for at least 15 minutes. Do not use solvents on skin
- Eye contact (any chemical): Rinse with clean water continuously for 15 minutes. Seek medical attention if irritation persists
- Hot glycerine burn: Cool immediately under running cold water for at least 10 minutes. Do not apply ice. Seek medical attention for burns larger than the palm
- Inhalation (primer/resin vapors): Move to fresh air immediately. If symptoms persist (dizziness, throat irritation), seek medical attention.

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PPE - Personal Protective Equipment

- Nitrile gloves

- Safety glasses

- Mask

- Apron

- Ventilated workspace at all times

- Thermometer

Group with some PPE

5) Final project advances

Devices

Design sharp body box

Considering sharp dimensions

Transparent material - acrilic windows

Water proof box

Considering different designs and water and pressure resistance materials

Body box and spaces for wires and screws

Box view

Box view. Sharp space and acrilic window

Box tolerance and hermetic seal space

Hermetic seal tolerance

Battery space

Final project page

6) Final results

• Linked to the group assignment page and reflected on your individual page what you have learned
• Review the safety data sheets for each of your molding and casting materials, then made and compared test casts with each of them
• Documented how you designed and created your 3D mold, including machine settings
• Ensure your mold has smooth surfaces finish, that does not show the production process (by postprocessing if necessary)
• Shown how you safely made your mold and cast the parts
• Described problems and how you fixed them
• Include your design files and hero shot of the mold and the final object

7) References files

We learn how to molding & casting materials, including design and create my own 3D mold

• File in Rhino 4 accesories - 3D printer
• File in Rhino Base - 3D printer
• File in Bambu Studio file - Huaco piece
• File in Bambu Studio file - Base
• File in Bambu Studio file - Accesories
• File in Rhino Mold 1 - part 1
• File in Rhino Mold 1 - part 2
• File in Rhino Mold 1 - part 3
• File in Rhino Mold 1 - part 4