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.