I managed to get my Astrocam into the air back on September 27; on this, its only flight so far, the flimsy body tube suffered some damage. As I mentioned back in this post, I was worried that the rocket would not last long, and had started designing a new Astrocam carrier rocket using a normal strength BT-50 tube and the Generic fin can. However, the design, which you can see below, never really caught my fancy - guess I have built too many of the E2X Generic series of late.
|My initial Astrocam carrier design (Click to enlarge).|
Yesterday, I was searching through an old parts box (the rain outside precluding any other rocket activity) and came across my old Estes Camroc. Then I remembered that the first carrier rocket for the Camroc was the nice-looking 2 stage Astron Delta, and that it was also BT-50-based. That's when the notion struck me - I could build a Delta, and have it loft both my Camroc (now non-functional) and the Astrocam. Forget designing my own - it was time to go old school!
|The Astron Delta in the 1972 Estes catalog (Click to enlarge).|
The first thing to do when building an old design from scratch is to grab the instructions and review the parts list. This I did, and I realized I had all the parts, including some spiffy laser cuts fins from Semroc, which would make life much easier. I had started pulling the pieces from my bins when I noticed something funky about the JT-50C couplers. Of the 6 I had, 3 were 1" in length and the others were 1.5" long. But the labels on all six said 1.5", contributing to my "WTH" moment. The 3 short couplers were from the older Carl Semroc days, and the long new ones were bought after eRockets took over, which was suspicious, so I glanced at the Delta instructions. It had drawings supporting the 1" length of the JT-50C. I then got online and consulted the 1974 Estes Custom Parts Catalog (a sacred tome to us cloners) and it gave the length of the coupler as 1". Be warned, fellow scratch builders - the eRockets JT-50C is 0.5" too long - probably not an issue in most builds, but ya never know. My guess is that Randy took the the typo on Carl's label seriously and made all his JT-50C couplers 1.5" inches in length. But the original JT-50C was definitely 1" in length.
The other "WTH" moment came when I tried locating the launch lugs called out in the Delta instructions - 2 LL-1B's. I couldn't find any in my large launch lug stash, so I consulted the parts catalog to get the lengths, figuring I would cut two larger lugs to the right size. Guess what? There was no entry for LL-1B, or LL-1 anything in the catalog - only LL-2A, LL-2B, LL-2C and LL-2D. Scratching my hairless head, I did some more googling and discovered that Estes had changed the part numbers sometime around 1970, with the LL-1B becoming the LL-2B. Those I had, so all good.
I have gathered all the Delta parts into a "kit", ready to start the assembly process. Which isn't going to happen for a while - I have 5 projects needing to be completed, and I promised myself no new builds until they are done. But I really, really want to build the Delta, so I'm hoping to channel this desire into action on the build backlog. Maybe I will be able to start on my camera carrier in December.
|My Delta "kit" (Click to enlarge).||My vintage Camroc (Click to enlarge).|
We shall see...