X-Git-Url: https://git.gag.com/?p=web%2Fgag.com;a=blobdiff_plain;f=rockets%2Fresearch%2Ftest1.mdwn;h=3b1ab6ba45e88380e564631d9836277252847a2f;hp=033b137b408d1888aaff6760c1e4329ad1174565;hb=b741d1a32d9390b08a72bc388094a00713b576a3;hpb=9b2e94aa9e8a55c8b17f31237db1d41a09e685c7 diff --git a/rockets/research/test1.mdwn b/rockets/research/test1.mdwn index 033b137..3b1ab6b 100755 --- a/rockets/research/test1.mdwn +++ b/rockets/research/test1.mdwn @@ -1,7 +1,7 @@ # Test 1 # -Robert and I decided to start out with a Sorbitol mix. Following -[Scott Jolley's](http://ajolleyplace.com/scott.html) lead, Bdale procured +We decided to start out with a Sorbitol mix. Following +[Scott Jolley's](http://ajolleyplace.com/scott.html) lead, we procured a sample of Polystep-B1 surfactant to make the propellant pourable. A quick burn simulation suggested 3 grains in an Aerotech 38/360 case with @@ -21,6 +21,8 @@ good grain after saw / knife kerfs. ## Formula ## +Since we need 177 grams, let's make 200 grams of propellant in this batch. + * 65% Potassium Nitrate (130g) * 35% Sorbitol (70g) * 1% Red Iron Oxide, added post-melt (2g) @@ -28,6 +30,8 @@ good grain after saw / knife kerfs. ## Process ## +The grains were cast on 30 May 2015. + We measured out the potassium nitrate and sorbitol into a sealable plastic container and shook vigorously to break up the clumps in the sorbitol and get a good physical mix. @@ -56,3 +60,14 @@ actually. About 4 hours later, the card stock was pulled off the test strand, which proved to still be a bit on the pliable and "tacky" surface side. + +## Observations ## + +After casting, further reading on Nakka's site indicates initial melt is +at about 91C, or 196F. Fully melted at 125C, or 257F. Discoloration at +175C, or 347F. + +Nakka says wait 24 hours before trying to pull the core rod. The propellant +will remain pliable after cooling, thus can be deformed if handled sooner. + +