Let’s make a silicone actuator that bends with air! We will make the mold for casting the silicone with a 3D printer.
- 40g (depends on mold size) Ecoflex silicone rubber 00-30 (Smooth-on, Inc.)
- Disposable mixing stick
- Disposable gloves
- Disposable cup
Tools and Equipments
- 3D Printer
- Kitchen scale
Design the bending actuator’s mold with 3D CAD software. Save as an STL data.
Download file here : Silicone_Bending_Actuator_STLdata
Print it with a 3D printer. There are 3 molds to make the bending actuator.
Measure equal amounts of Ecoflex 00-30 part A 40g and part B 40g. Slowly mix the silicone with a mixing stick for 1 minute. Avoid brisk mixing movements to prevent from making bubbles. Mix well while scraping the silicone from bottom and side of the cup.
Please check the details about casting here.
Pour the silicone into the molds. Wipe off the overflowed silicon with a paper towel. Leave the silicon rubber for 10 minutes for degassing. For simple molds, vacuum pumps are not necessary because Ecoflex’s viscosity is not that high.
Wait more than 4 hours. Take the silicone out of the molds.
Repeat the “Mix” step. In this time, we measured equal amounts of Ecoflex 00-30 part A 12g and part B 12g.
Attach the two parts of silicone. Wait more than 4 hours.
Inflate it with a air pump.
- Download file here : Silicone_Bending_Actuator_STLdata
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