Tuesday, November 10, 2009

Some actual building!

Amazing, I know.

Most of the work was on the Great Pumpkin - my pumpkin lofter for the November 'Pumpkin Chunkin' contest at CATO. It'll be 4" maximum diameter and about 30" long when finished.

I knew I needed a 4" payload bay for the pumpkin, but I only had 3" tubing, so I cut a 6" length, cut a slit, and glued another piece across the opening to form a 6" piece of 4" tube. I've also glued on a few other bits for reinforcement.

I found an old foam cone, and got permission from my mom to cut it up. I cut a 2" core out with a hole saw, and it now will form a nice solid transition from the 4" payload section to the 2" main body tube. It's currently gluing to a 4" plywood ring, which I cut out with a handsaw.

For the motor mount tube, I cut a 6.5" section of 29mm tube. I took two 1/4" thick plywood rings, drilled a 1" center hole with a spade bit, and then used a dremel tool to extend the hole to 32mm for the 29mm motor mount tube (which is 32mm outside diameter). The aft ring is currently gluing to the tube with wood glue.

I also started work on one of the Baby Berthas, which'll become the Nike Goon. I assembled the motor mount and modified the nose cone so that the streamer can fit inside, plus I put a little clay in the tip of the nose cone for stability.

I'll cut the fins tomorrow. They'll have TTW (through the wall) tabs that attach to the motor mount, and they'll be scale-sized Nike fins - exactly 1/10 the original size. That is; 2.34" root edge, 1.21" tip, and 2.16" wide. The original Nike boosters were 16.5" in diameter - exactly 10 times the 1.65" of the BT-60 of the Baby Bertha.

(Thank you Rockets of the World)

No comments: