MMC60 Switch

Device Details

Overview

The MMC60 Switch is a cost-effective, 3D printable accessibility switch. The switch has a 60 mm (2.5 inch) round activation surface and uses a standard 3.5 mm cable. The switch is 40 mm in height. Using the specified switch, the activation force is about 3.4 N (325-350 gf). The cost in parts is approximately $10 in hardware and 3D printing materials. This switch has a button top that screws off, making it easy to swap to a customized top.

A number of these switches are being built by volunteers at Microsoft and then by youth at the BCTECH Summit March 19, 2019. This switch has also been referred to as the “Round Flexure Switch” and “Tough Switch”.

Usage

The switch is activated by applying pressure on the top surface. This switch can be connected to any standard AT interface, and can also be used with the Xbox Adaptive Controller. The switch can be used on a flat surface or mounted using the 1/4″-20 UNC connection on the bottom.

The top button / activation surface is attached to the base by threading it on. This makes it easy to change tops to change color, labels, etc.

Build Instructions

Bill of Materials

1 – 3D Printed Base Bottom

1 – 3D Printed Base Top

1 – 3D Printed Flexure

1 – 3D Printed Button

1 – 3D Printed Switch Mount

1 – 3D Printed Pins

1 – 3.5 mm mono cable (e.g. https://www.digikey.ca/short/pt54w9, ~$4.50 OR try local dollar store)

1 – Microswitch (Omron SS-3GP e.g. https://www.digikey.ca/short/pq1dvb  ~$0.88)

1 – Mono Jack (CUI MJ3502 https://www.digikey.ca/short/pq1d1z ~$1.32)

1 – 1/4″-20 UNC Hex Bolt, 1/2″ Length (e.g. https://www.mcmaster.com/92865a537, ~$ 0.12)

2 – 1/4″-20 UNC Hex Nut (e.g. https://www.mcmaster.com/95462a029, ~$0.15)

1 – 1/4″-20 UNC Tee Nut Insert, 5/16″ Length (e.g. https://www.mcmaster.com/90975a025, ~$0.17)

5 – #4 Metal Screw, 3/8″ Length (e.g. https://www.mcmaster.com/90190a108, ~$0.46 OR https://www.amazon.ca/gp/product/B00GI86MW8 )

2 – 4 cm length 22 AWG wire

Tools

• Soldering iron
• Wire strippers
• Flush cutters
• Screwdriver
• Crescent Wrench OR 7/16″ Wrench

3D Printing

The parts were designed to be printed with a 0.4 mm nozzle, and a vertical resolution of 0.2 mm. Two of the parts should be printed with support: R1_Base_Bottom and R1_Button. All the parts should be printed with two walls/shells except the flexure, which should be printed with 4 walls/shells. An entire set of components for a single button takes about 4-4.5 hours to print.

Assembling the Switch

Download the PDF for detailed assembly instructions.

Custom Switch Buttons

The MMC60 Switch has an easily swappable top so users can customize their setup. There are buttons design that are plain and flat, textured, and ones that include symbols and text. This is a great way for users to differentiate between switch functions if there are multiple switches in close proximity or for applications like adapting gaming. Find the gaming button files in the resources section on this page or add your own custom patterns and text with this tutorial.

Bill of Materials

1 – Assembled MMC60 Switch

1 – MMC60 Switch Customized Button

1 – 1/4″-20 UNC Hex Nut (e.g. https://www.mcmaster.com/95462a029, ~$0.15)

Assembly

1. Remove the switch button from an assembled MMC60 Switch by turning counter clockwise.

2. Remove the support material from the customized switch top.

3. Insert one 1/4″-20 UNC Hex Nut.

4. Install the switch button by turning clockwise onto the MMC60 Switch.

Design

This design was created by Makers Making Change using Fusion 360. The switch used a radial linear flexure to support the button. The switch mount is intended to be a modular component so that other switches could be used.

Attribution

Designed by Makers Making Change. Elements of the design, including the use of a flexure, were inspired by the Volksswitch and the DIYAT Switch V5.