777 Parlour Slot
A dark cabinet, a tan faceplate with a 777 marquee, and three reels of sevens, BARs, cherries, bells and lemons. Pull the lever and the reels turn, each by a different amount, then sit square in their windows.
No coins, no payout, no electronics. Just a lever, a shaft and some teeth.
Follow the pull
Scroll, and the lever goes forward to its stop. Partway through, the cabinet fades so you can watch the drive move from your hand to the reels, one part at a time.
It starts at your hand
Nothing in this cabinet is powered. Every bit of motion begins at the black knob on top of the lever.
The lever
The lever swings forward, toward you. Its hub is keyed to the cross shaft, so the shaft turns exactly as far as the lever does.
One shaft for all three
With the cabinet faded out you can see it: a single shaft runs the full width under the reels, carrying one toothed sector under each reel.
Three rows of teeth
The sectors carry 7, 9 and 11 teeth. The longest row reaches its reel first: right at 19° of lever travel, centre at 33°, left at 48°.
Geared up
Each sector tooth pushes its reel round one tooth of a 16-tooth pinion, so a reel turns 3.5 times as fast as the lever. Two pinion teeth make one face.
Square on a face
Behind each reel, a printed finger rides a star wheel with 8 notches. It drops into the nearest one and holds the reel square in its window.
On the stop
At 75° a pin in the cabinet back meets the end of a slot in the left sector. The right reel has moved 4 faces, the centre 3, the left 2.
Why the reels never move together
All three sectors sit on the same shaft and turn through the same angle. What differs is how much of each one is toothed. A longer row of teeth starts working earlier in the pull, so its reel travels further before the lever reaches the stop.
Drawn from the CAD at rest, seen from the lever side: each sector cut through its teeth, with the reel's 16-tooth pinion and its 8-sided rim above. The dashed line joins the two axles.
After a pull
The lever ends nearly level, pointing at you, and the windows show where the reels landed: in this photo, a BAR, a cherry and a BAR.
Every symbol sits square in its window because the detents never let a reel stop between faces.
The machine
- Size
- 5.1 × 3.1 × 6.4 in, width by depth by height, lever upright
- Weight
- 10.6 oz
- Printed parts
- 20, in PLA
- Reels
- 3, with 8 faces each
- Gearing
- 7, 9 and 11-tooth sectors into 16-tooth pinions
- Lever travel
- 75° to a moulded stop
- Power
- Your hand. No coins, no payout, no electronics.