Brief:
This is a scratch 2X upscale of a popular Estes kit. It features a 3 inch diameter body and PML components (except the nose cone, which was turned on a lathe out of solid pine). It weighs 3.5 pounds and is 45 inches tall.
Construction:
A 36" long, 3" diameter quantum body tube was ordered with fin slots custom cut for .062" G-10 fins. The G-10 fins were ordered custom from PML and cost $8.50 each. They were up-scaled from the Estes kit fin pattern with through-the-wall tabs for mounting to a 38mm motor mount tube. A 3" piston assembly, 1/4 inch brass launch lug (10" long, also upscale), and an 18" 38mm motor mount tube with three centering rings was also ordered from PML. All of these components were obtained within two weeks of placing the order. Motor retention was accomplished by epoxying two pieces of threaded rod to the motor mount tube. Standard PML construction techniques were employed to build the rocket including internal fin fillets and piston strap attachment to the upper motor mount tube. The nose cone was turned out of pine on a lathe. A search was conducted on the internet for a suitable 3 inch nose cone, but the only one found was too expensive. I decided to apply my knowledge from 9th grade shop (when I made a lamp out of light and dark mahogany by gluing 1x4 together) to make my own solid pine nose cone. I used pine because I wanted to make sure it would be stable on BIG engines. The finished nose cone ended up weighing 12 oz. by itself.
Finishing:
I sprayed a coat of grey Krylon sandable primer, then followed with two coats of Krylon gloss black. I still need some upscale decals.
Flight:
This was my level 1 cert rocket, so I used the chute from my PML 'lil Luner Express and about 25 feet of shock cord, loaded an H123W with a medium delay, and let it rip. Rocksim predicted about 1200 feet and that looked about right.
Recovery:
It ejected at apogee, and drifted down for a soft landing on the sod. It returned in triumph for a successful certification flight.
Summary:
A fun time was had by all. My thanks to Leland Cheng for loaning me a motor case and selling me a motor, Alan Estenson for being my certification observer, and Tripoli chapter 45 for hosting the launch.
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