-# Batch 2019.01.08 #
+# Batch 2019.05.21 #
-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
+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
cut, cored, and trimmed.
The 54mm casting tube I'm using weighs 1.84g per inch.
-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
+Third time mixing APCP propellant. Again used the 4.5qt mixer and hand
+packed with no vacuum processing. Same formula as previous batches.
-These grains were cast on 2019-01-08.
+These grains were cast on 2019-05-21.
## 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, 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.
+* 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