DIY SUGRU Switch
This guide explains how to build inexpensive foot pedals that act as standard accessibility switches. Using SUGRU this method does not require any soldering.
Most of the equipment used here is commonly available from Electronics stores such as Maplin Electronics and Farnell. The Tattoo foot pedal switches are easily found on eBay for under £4 delivered. The ones I use here are "Acrylic Tattoo Pedal" and "Skull Tattoo Pedal".
SAFETY: Be careful when stripping wires of the plastic coating using a knife as it is easy to cut yourself. Ideally use proper wire strippers. Additionally, these foot pedals should be used under the supervision of a responsible person where appropriate.
For additional help with this adaptation, please feel free to contact me directly at OneSwitch.
1. What you will need
Optional: Pliers, Wire Strippers and ruler.
Note: If you replace the SUGRU fixing with solder (assuming you have a soldering iron) or glue you will of course reduce costs further.
2. Cut off plug
Carefully cut off the 6.35mm plug connector. This is too big for modern day switch accessible assistive technology. We need to fit the smaller 3.5mm one.
N.B.Unscrew your new 3.5mm mono plug, and then thread your wire through it (image of black-wire from Acrylic Tattoo pedal adaptation).
3. Strip the wire ends
Split the two wires apart (about 1.5cm), then strip the tips off (about 8mm one side and 12mm the other). Twirl the wires a few times to make them tight and easier to thread through the two holes in the plug..
4. Wire Up Plug
Thread the 12mm length through the bottom hole, and the 8mm through the top hole of your 3.5mm plug. There should be enough wire to wrap them around onto themselves as tightly as you can against the metal, ready for fixing into place.
5. SUGRU
Cut out and roll thin sausages of SUGRU to insulate and hold the wires into place. Ideally, use pliers to wrap the metal tags at the bottom of the plug around the plastic coated wires to hold them into postion better.
When ready, screw the black plastic barrel casing over the SUGRU, cleaning away any excess as you go. Carefully use pliers if you don't have the strength to fully do the plug up together. You should end up with something like the switch at the top of this page.
SUGRU takes about a day to cure, but if you're careful, you can use your foot pedal switch straight away. Remember to always hold onto the barrel of the plug to connect and disconnect. Don't pull from the wire to remove your foot switch as you could break the connections inside.
6. Test
The fun bit as always (if it works first go) is testing your switches. I'm using a DIY solderless PC Switch interface above, which allows me to test the buttons with the "Set up USB game controllers" utility (found by typing that into your Start search bar text box). You can just as well use any other switch accessible device of course.
If all works as you planned, then well done! Maybe time to move onto the PC Switch Interface next?
D.I.Y. Text and images PUBLIC DOMAIN 2013 - www.OneSwitch.org.uk
