There are other methods to get free slot play and many were used when slot machines were not so highly developed. But again, slot machines now rule out the coins, which don't measure up to the size of the coin required and so this trick no longer works either. Some people realized that if you shaved about 0.040' off a quarter, the slot machine would detect the coin and shoot it back out, so you get similar results to the string and coin method but without a piece of string hanging out of the machine. There are very few machines where this trick will work now. But now it'll most likely keep your coin or just make no effect as the machines are now usually able to detect the strings. They would drop the coin in the machine and pull it back out. But this can be quite a difficult task as slots machines have been massively developed into what they are now in order to prevent people playing for free as this is very illegal.īefore the massive development of slots, some people were able to pay for free by attaching a piece of string to a coin. If there is a way of doing it, it is hugely restricted and so there is no way of us finding out unless we work it out for ourselves. Unfortunately, there is no way to get free slot play at San Manuel Indian Bingo and Casino.