Jeff, This 'stuff' is made in 'biscuits' that start out as big as 50" x 50" x 192" (some are maybe much bigger) and is then cut to the sheets you purchase. When you're down to measuring grams, it's surprising that the density is as uniform as it is. If you cut cores from the pieces you weighed you'd probably find that they reflected proportionately the weights of the original blanks. Jim Porter Bettendorf, Iowa ----- Original Message ----- From: Jeff Winder <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, January 12, 2000 9:13 AM Subject: [RCSE] Foam Mystery.... > Just started my winter foam cutting frenzy for next season's HLG batch and > noticed something really strange. The local building supply company was out > of the usual Dow Blue extruded basement foam, so I purchased some of the > Corning Pink stuff. The Pink was the same thickness as the Blue, 1.5" and > the same R value 7.5, so I thought that this stuff would weigh about the > same. To check this, I cut two 15.5" by 7.25" blocks (1 from the Corning > Pink, and 1 from a leftover piece of Dow Blue), then went to the gram scale > and weighed each. Turns out, the Dow Blue piece was 6.5 grams lighter. > Logically then, a core cut from the Dow Blue should be lighter. This was not > the case! After cutting a core using the same airfoil templates on each > piece, the Corning Pink core weights 2.2 grams less, even though the block > it came from weighs more!! Both cores are the same length, and thickness > ...... > > Anyone got an answer? > > Thanks Again, > Jeff Winder > [EMAIL PROTECTED] > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
