I'm so cheap! >:(I bought some 50 grit sand paper and cut it to fit in a 1/2 gallon plastic peanut butter jar, sides, lid and bottom. I used spray glue to stick it. Shake and roll the balls for 15 minutes and the balls come out sweet! I think that they make harder contact from shaking rather than rolling like tumblers do and that is why they come out so good after only 15 minutes. They are good for a couple weeks and then I do it again.