The Raindrop is small, simple DIY assistive switch. The activation surface is 20 mm in diameter and the activation force is about 1.3N (130 gf). It has a similar size and activation force as the AbleNet Mini Cup Switch, at a fraction of the cost.
More details can be found at the MMC Open-Source Assistive Technology library project page:
To assemble the switch, you'll need:
1 - 3D Printed Switch Base (~ 1.3 g of filament, $0.07)
1 - 3D Printed Switch Cap (~ 1.0 g of filament, $0.05)
1 - 3.5 mm mono cable (e.g. https://www.digikey.ca/short/pt54w9, ~$4.50 OR try local dollar store)
1 - 12 mm tactile switch (e.g. Omron B3F-5050, https://www.digikey.com/short/jvzq2d, ~$0.50)
~1/3 - stick of hot glue
1 - 3D Printed 12 mm switch soldering jig ( ~5.0 g of filament, $0.25)
This model of 12 mm tactile switch was chosen for its low activation force and long lifetime. Other models of 12 mm tactile switches may be used, but may result in higher required force.
Assembly instructions available here:
Volunteer your 3D printing skills to help people with disabilities in your community!
Makers Making Change is an initiative of the Neil Squire Society, a Canadian non-profit that helps people with disabilities.We are committed to creating a network of volunteer makers who support people with disabilities in their communities through 3D printing assistive devices. Check out our library of free, open-source assistive technologies with parts and build instructions.
- Removed MMC logo from thin wall section on base