Part III: Slot Machine Cheating · Physical Cheating Methods

SCAM #1: The Yo-Yo (Coin-on-a-String / Stringing)

How it works

The oldest and most fundamental slot machine cheating technique. The cheat attaches a string (dental floss, nylon line, or thin wire) to a genuine coin – either by taping it or drilling a small hole through the coin – and inserts it into the coin slot. The coin passes the optic or mechanical sensor, registers a credit, and is then pulled back out by the string. The cheat can repeat this process dozens or hundreds of times, accumulating credits while only using a single coin. Some cheats used a small object like a cigarette lighter wrapped in tape to conveniently attach and detach the string from the coin while in the casino.

Where it appears

Older coin-operated slot machines with mechanical or basic optical coin acceptors.

On the record

Known as “the godfather of all slot machine scams” by Mob Museum experts. James Taylor, Nevada Gaming Control Board Enforcement Division chief, noted that his first criminal arrest was of individuals using yo-yos in 1995. Some yo-yo devices were sophisticated enough to include a paper clip and ballpoint pen spring mechanism that fit into the coin acceptor slot.

Published as a detection reference for surveillance, compliance and gaming-operations professionals. Thresholds and tuning are set by the property. Nothing here is instruction — the method is described so it can be recognised.