Fairmouse: A Computer Mouse from recycled plastic

Completed

johannplasto

| Started 10 months ago

Last update 4 months ago

Moulds

Fairmouse: A Computer Mouse from recycled plastic

The idea is a computer mouse made of recycled plastic. The aim is to find a design that allows the mouse to click properly. The design should be minimalistic & ergonomic. The electronics should come from sources that are as fair as possible (see Nager-IT). Phase 1: Design phase •Bottom part that holds the electronics. •A 3D-Printing prototype, that is easy to click. •Parts suitable for injection moulding. •Minimalistic & ergonomic mouse design. •Mouse wheel also for injection moulding. •First prototypes from recycled PET-Bottles. Phase 2: First prototype mould •3D-Printed mould •Test injections to check injection & demoulding. •Testing first mouse prototypes from recycled plastic. •Design changes based on testings. Phase 3: Final Mould •CNC Milling 3 Moulds (Mouse Base, Mouse top, Mouse wheel). •Manufacturing (Soldering electronics, mouse parts). •Make the most possible fair mouse (Fairmouse)

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12 steps

1

Design phase

created 10 months agoedited 8 months ago

CAD design of the mouse design. Steps: •Bottom part that holds the electronics. •A 3D-Printing prototype, that is easy to click. •Parts suitable for injection moulding. •Minimalistic & ergonomic mouse design. •Mouse wheel also for injection moulding.

2

Design phase: Version 1

created 9 months agoedited 9 months ago

This version is an attempt to design an ergonomic mouse shape that allows the palm to rest on it. This relieves the wrist and prevents tendonitis, which affects many users who spend a lot of time with a mouse. The first prototype already felt very comfortable, but it lacked a side grip that allows you to easily lift the mouse with your thumb and little finger to reposition it. Since we could equip the prototypes with the circuit board right away, several people tested them for several days, which made such necessities clear. However, the biggest drawback of these versions is fine mouse adjustments, which are only possible when the palm rests on the table and fine movements are made with the fingers. Therefore, these versions are being discarded, and the focus is shifting towards smaller mice.

3

Design phase: Version 2 - Minimalistic version

created 8 months ago

1. Minimalistic and Flat Design The new version of the computer mouse has been engineered with a minimalistic and flat design. This design approach ensures that the mouse is as slim as the underlying electronics allow, offering a sleek and modern appearance. 2. Button Click Resistance One identified issue with the current prototype is the excessive resistance of the mouse buttons. Users find the buttons too difficult to click, which can lead to discomfort during prolonged use and may affect overall user experience and productivity. 3. Ergonomic Concerns The current design also presents ergonomic challenges. The curvature of the mouse is insufficient, resulting in edges that cause discomfort by pressing against the palm. This lack of ergonomic consideration means the mouse does not fit well in the hand, potentially leading to strain and reducing comfort during extended use.

4

Design phase: Version 3 - Final design

created 8 months ago

1. Ease of Clicking To tackle tolerance issues, we have incorporated screw bosses that allow for the insertion of fine screws. These screws enable precise adjustment of clickability. Additionally, the bending edges of the buttons have been designed with a groove, allowing for a thinner wall thickness that facilitates easier bending. 2. Tolerances All tolerances, including those that were previously too small or too large for the integration of electronics, as well as the tolerances between the upper and lower shells, have been perfected. 3.Shrinkage For the future injection-molded mouse, we have accounted for a shrinkage value of 2.5% for polypropylene.

5

Prototype mould

created 8 months ago

The injection tests were successful. Despite the narrow gap for the mouse button groove, the mouse was fully injected. The mouse, made from recycled polypropylene, is even easier to click than the 3D-printed prototypes. The measured shrinkage is smaller than the assumed shrinkage value of 2.5%, which will need to be adjusted for the final mould.

6

Final Mould - Design

created 6 months ago

After testing the prototype from the 3D printed mould, the final adjustments were made: -Tolerances for the circuit board insert -Tolerances for the lens insert -Screw domes for the mouse buttons -Shrinkage applied for polypropylene (2.5%) -Draft angles as large as the geometry allows With these changes, the aluminium moulds could be constructed (1x mould for the upper shell, 1x mould for the lower shell). The only differences to the 3D printed mould are the nozzle design and the use of threads in the lower moulds. Aluminium 7050 is chosen as the material (very good properties for injection moulds). The visible surfaces are glass bead blasted.

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7

Final Mould - Aluminium CNC

created 5 months agoedited 5 months ago

The mould was CNC milled in an external workshop based on the 3D data and drawings. The use of 2 dowel pins per mould ensures perfect positioning of the upper and lower moulds. This is where the precise tolerances in the drawings pay off. The M8x30 hexagon socket screws ensure tight moulds and protect against flushes and destruction of the moulds.

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Final Mould - Injection

created 5 months ago

The recommended type of plastic is polypropylene because of the relatively thin wall thickness (about 3mm overall, and only 0.8mm at the button bends). Both mouse parts can be easily injected at 170°C.

9

Final Mould - Demoulding

created 5 months ago

After removing the screws, the mold halves can be opened using the demoulding pockets. You can knock the parts out of the mold using a hammer and punch. The precise shape means there are no flushes, which makes rework easier.

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Final Product - Afterworks

created 5 months ago

The finishing work includes cutting off the sprues, drilling the screw holes and inserting the button screws. The setting height is fine-tuned again after the complete assembly.

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Final Product - Soldering the electronics

created 5 months ago

All electronic components come from the Nager-IT association. They are on a mission to make electronics as fair as possible. To this end, they offer the Nager-IT mouse and do a lot of educational work to raise awareness of the problems in the electronics industry (critical raw materials, electronic waste & working conditions). Since I deeply admire this endeavor, I have been following Nager-IT's work for a long time, have taken part in a multiplier workshop and have given soldering courses myself. Making the cover for this mouse out of recycled plastic has been a dream for a long time. The special thing about Nager-IT is the complete breakdown and transparency of the supply chain. From the raw materials to the end product! At the beginning, a minimalist mouse was developed, the components of which also contained as few critical raw materials as possible, such as cobalt, and the components were manufactured under fair working conditions. Over the years, the association has invested a lot of work in checking the working conditions of the sub-sub-suppliers, but this is almost impossible, even down to the raw materials, which is why the presentation of the supply chain honestly shows how far they have penetrated and one can at least say with certainty that the mouse can be fairly rated at more than 70%, which is a major milestone in the electronics industry. I made instructions for soldering the circuit board some time ago and can be viewed clearly at Instructables: https://www.instructables.com/How-to-Make-a-Fair-DIY-Computer-Mouse/ Also check out Nager-IT: https://www.nager-it.de/en/projekt

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Final Product - Final Assembly & Test

created 5 months ago

The final steps are inserting the lens, the circuit board and screwing the top and bottom together. After testing the click for the first time, the button adjustment screws can be adjusted to achieve the best click feeling. Finally, the gliders are glued on, which allow the mouse to glide smoothly on the table. The mouse is connected to the computer via USB, is automatically recognized by all common operating systems and can be used straight away. Optionally, the mouse can be checked with an online mouse check. That's it, probably the fairest computer mouse in the world! :) What do you think? Feel free to leave your comments and follow @johannplasto to keep up with the latest news about the mouse and other products and projects made from and about recycled plastic. Happy recycling! Thomas @johannplasto

Precious Plastic is a project by One Army.Please sponsor the work or help us build the software.