Peter Balch - Home

A Steampunk Mouse

Every self-respecting Victorian Scientist needs a brain in a jar.

Why a Brain? Well, it's an optical mouse - it looks at the ground and works out how far the ground has moved. How would a Victorian do that? How can you do it with a mechanical difference engine? You can't - you don't have enough computing power. But a brain could be made to do the job. Clearly, that's how Baron Frankenstein, the ultimate hacker, would make an optical mouse.
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Length 90mm; Width 60mm; Height 75mm.

How it was made

Start with a standard optical mouse with a fairly small footprint.
Take a photo of the pcb layout to trace the tracks if needed.
Remove the microswitches and the wheel encoder.
The ring from a light fitting and a coin make a nice mouse-wheel.
A hexagon head is filed onto a brass rod to make an axle
The parts are assembled on a piece of stripboard. Brass wire is used as stilts to raise the axle and the mouse-wheel button
Blocks of wood are carved to enclose the wheel-encoder and wheel-button.
The pcb is cut down to size. Enamelled-wire is used to replace the lost tracks.
A thin ply baseplate is cut and the pcb and stripboard screwed onto it. Small wooden pads will support the dome.

It's important to get the right distance from the sensor to the ground - the depth of focus is fairly small. Measure the original mouse.
Brains have eyes, of course. Could I use them instead of mouse buttons?

I made these eyeballs using small reflective photosensors and wooden beads. I just connected each phototransistor across where the mouse button should go and they worked fine with a finger. That was a bit surprising - I'd expected the reflection to go away when I touched the sensor but I guess skin acts like an IR light-pipe.

They were confused by reflections from the inside of the glass dome but that could be solved by pressing the eyeballs up against the inside of the glass dome. The sensors protrude very slightly from the balls to make that possible. But then I tried it in daylight and the phototransistors were overwhelmed. Even with Scottish daylight near a North facing window.
So I used gold plated bronze contacts (salvaged from scrap electronics) to make the mouse buttons; there's not enough room in the wooden blocks to fit microswitches.
The wood is stained.
A shoelace covers the mouse cable to give it a Victorian look.
The dome is from a Victorian gas mantle.
The brass gallery rail is from a fake oil lamp found in a car-boot sale.
The brain is made from Fimo wrapped around an egg-shaped piece of wood. The electrodes are enamelled copper wire and pins. The cage is brass wire, a nut, a screw-cup and a thumb-tack all soldered together. A colour-changing LED is glued inside the nut and connected in parallel with the optical-mouse's LED.
The gallery rail is glued on.

The underside is stained and the nylon feet from the original mouse added to reduce friction.
The dome and railing are glued into place and it's finished.

Two weeks later . . . . . . . How well does it work?

The round glass dome makes it comfortable to hold and it slides well over the desk. The mouse wheel is excellent: it spins fast and has a lot of momentum. It's great for scrolling through long documents.

The "mouse button" contacts are reliable but a little heavy to use. They lack tactile-feedback. I will find a way to fit microswitches in the next mouse.

And to accompany the mouse, here is a memory stick.

Other projects:
Hacking an antique clock
Old Telephones
An Orrery-Clock
A steampunk mouse
A 1960s webcam
A sgian dubh memory stick
A wheeled mouse
An external disk drive
A 1930s webcam
A Vintage Intercom