Product review for Ball and Ring Device Please read our review guidelines and see the terms of use of posting a review. Overall Rating: and share your thoughts with other customers Sort Reviews: Newest | Oldest | Highest Rating | Lowest Rating  NEXT :: Viewing page 1 of 2  -  Monday, November 19, 2007 doesn't work Reviewed By: LY (Walnut Creek, CA) handle was plastic, not wooden as advertised. I placed ball in boiling water for 5 minutes, but still did not expand enough to get stuck in ring. I put ring in the freezer for 5 minutes and the ball back in the boiling water for another 5 minutes, but still the ball did not expand enough to not fit through the ring. My guess is that a miscalculation was made on the thermal expansion of the metal.  -  Monday, July 14, 2008 Out of Spec Reviewed By: DCE (Parsippany, NJ) I had similar results to "LY (Walnut Creek, CA)" however, my handles are made of wood (painted Black) as advertised. Otherwise they would probably have melted while trying to get this item to demonstrate the desired affect. I am an engineer and found that the tolerances between the Outside diameter of the Ball and the Inside Diameter of the Ring are too great to demonstrate the effect without risking unecessary injury. I first heated the ball using a heat gun to the point that it burned my skin when I touched it. It still passed smoothly through the ring. I then put the ring in the freezer for an hour. just before removing the ring I again heated the Ball with a heat gun, then tried to pass the ball through the ring, but again it passed without resistance. I could hear the frost on the ring hiss as it touched the hot ball, but could not demonstrate the effect as advertised. Eventually, I tried heating the ball with a propane torch. only then did the ball expand enough to resist going through the ring. Tolerance on the production items may need to be reduced a little.  -  Sunday, January 11, 2009 ball and ring device out of tolerance Reviewed By: Houston (Gaithersburg, MD) I heated the ball to sizzling temperature >200C and froze the ring to -25C and the ball still cleared the ring (with a sizzle from the frost). Conclusion: the several mm disparity in diameter is clearly out of specifications. Looks good, doesn't work. Background: Ph.D. Physiologist and Biophysicist.  -  Wednesday, January 14, 2009 Tolerances too loose Reviewed By: DS (Buena Vista, CO) I found that tolerances on dimensions are too loose to demonstrate thermal expansion without special equipment.  -  Wednesday, January 14, 2009 no good Reviewed By: debbie (new york, new york) the ball and ring apparatus simply does not work. i had it in boiling water for 10 minutes and it still easily fit through the ring. im disappointed because i know my students would have loved this. aren't these things tested before they are sold?

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