From: Bdale Garbee <bdale@gag.com>
Date: Mon, 27 May 2019 18:36:26 +0000 (-0600)
Subject: restore accidentally-overwritten copy of Jan 8th batch data
X-Git-Url: https://git.gag.com/?p=web%2Fgag.com;a=commitdiff_plain;h=f344014d8d7c5370c98228877251d93cb549ffcd

restore accidentally-overwritten copy of Jan 8th batch data
---

diff --git a/rockets/research/2019.01.08.mdwn b/rockets/research/2019.01.08.mdwn
index 569fa8b..0112b4b 100755
--- a/rockets/research/2019.01.08.mdwn
+++ b/rockets/research/2019.01.08.mdwn
@@ -1,25 +1,34 @@
-# Batch 2019.05.21 #
+# Batch 2019.01.08 #
 
-8 Terry-length Everclear grains for 54mm cases, with 0.625 inch cores, 
-cast as four 6-inch-long double grains with 0.5" delrin coring rods, then 
+4 Terry-length Everyclear grains for 54mm cases, with 0.625 inch cores, 
+cast as two 6-inch-long double grains with 0.5" delrin coring rods, then 
 cut, cored, and trimmed.
 
 The 54mm casting tube I'm using weighs 1.84g per inch.
 
-Third time mixing APCP propellant.  Again used the 4.5qt mixer and hand 
-packed with no vacuum processing.  Same formula as previous batches.
+This was my second time mixing APCP propellant.  Again used the 4.5qt mixer 
+and hand packed with no vacuum processing.  Same formula as yesterday
 
-These grains were cast on 2019-05-21.
+These grains were cast on 2019-01-08.
 
 ## Results ##
 
+The updated batch size was just right, there was a bit of excess propellant
+so we can make density and burn rate measurements after cure.  The excess
+weighed in at 17.9g after cure.
 
-* Grain 1, " long, g gross, g casting tube, g net
-* Grain 2, " long, g gross, g casting tube, g net
-* Grain 3, " long, g gross, g casting tube, g net
-* Grain 4, " long, g gross, g casting tube, g net
-* Grain 5, " long, g gross, g casting tube, g net
-* Grain 6, " long, g gross, g casting tube, g net
-* Grain 7, " long, g gross, g casting tube, g net
-* Grain 8, " long, g gross, g casting tube, g net
+* Grain 1, 2.980" long, 162.6g gross, 5.48g casting tube, 157.12g net
+* Grain 2, 2.970" long, 162.0g gross, 5.46g casting tube, 156.54g net
+* Grain 3, 3.010" long, 164.7g gross, 5.54g casting tube, 159.16g net
+* Grain 4, 2.995" long, 163.6g gross, 5.51g casting tube, 158.09g net
+
+The mass per unit length was within 0.1g/inch, which seems awesome.
+
+In total for this batch and the previous day's, which were post-processed 
+together at the same time, there was 10.4g sanded off the grain ends and
+64.7g of waste from core drilling the 0.5"-ish holes to 0.625".  Really
+leaves me wondering if it wouldn't be better to just start with the right
+size coring rod for future batches and avoid the coring waste.  Might leave
+me wanting to rough the cores for better ignition?  But, maybe not.  Something
+to ponder more.