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  -  Friday, September 18, 2009 It works! Just do it right! Reviewed By: Ken  (Saratoga, CA) people complaining about this don't realize that the temperature differential must be very high (at least 250-300 •F ?) I have always done this demonstration with flame (bunsen burner, propane torch, etc.) I have done this with kids 100s of times w/o a single accident! You cannot get high enough temps with boiling water or a heat gun!  -  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.  -  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.  -  Saturday, October 20, 2007 attention getter Reviewed By: Shawn (Colorado Springs, CO) This is really a great way to show kids how temperature can change things.  -  Sunday, October 11, 2009 Tolerances too loose Reviewed By: EC (Glenn Dale, MD) This is a disappointment. The tolerances are indeed way too loose to make a good demo.

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