Scratch Caution: Rocket Original Design / Scratch Built

Scratch - Caution: Rocket {Scratch}

Contributed by Jason Toft

Manufacturer: Scratch
(Contributed - by Jason Toft - 07/01/02)

Brief:
Small two motor cluster rocket with streamer recovery

Construction:
(1) 9.5 inch length o' BT-56 tubin' (1) 3 inch by 9 inch piece o' 1/8 inch balsa (1) 10 inch length o' BT-5 tubin' (1) 2 1/2 foot length o' 3-inch wide Caution Tape (1) BT-56 Nose. Blimey! Cone shape (2) BT-56 t' BT-20 centerin' rings cut to apporpriate shape Shock Cord o' your choice w/attachment method

I decided on this rocket one day when I was messin' around with Rocksim 5.0. I had always wanted t' build a cluster rocket, me hearties, but I wanted t' start small. Begad! Blimey! So, I went t' me local hobby shop, arrr, shiver me timbers, Ralph's Hobbies, ya bilge rat, and picked up a 18 inch length of BT-56 tubin' left over from a kit that had made it into his parts box. Arrr! Blimey! Well, blow me down! Blimey! I also got t' balsa I needed. Ahoy! Blimey! I picked up a few more parts from another hobby shop and came home t' start building. Ahoy! Blimey! Blimey! Blimey!

I cut a 9.5 inch length o' t' tubin' for t' body tube and set it aside. Then, me hearties, shiver me timbers, I cut 2 5-inch lengths o' t' BT-5 tube and glued them together and let dry. Well, blow me down! Ya scallywag! Then, take t' centerin' rings and drew t' shape o' t' two BT-5's on it. Now, for this part, make sure you have a very sharp blade. Ahoy! Ya scallywag! Cut around t' two centerin' rings on t' lines you drew and then glue them 1 inch from either end of t' motor tubes. Avast, me proud beauty! Avast! When dry, me bucko, matey, me bucko, insert into body tube w/glue. Make t' shock cord mount and set it aside. Ahoy! Begad! Now, matey, you can use any kind o' warnin' tape and theme the rocket lik! e t' tape, me bucko, me hearties, ya bilge rat, so do whatever you want t' it. Begad! Cut t' balsa into a trapezoidal shape. Avast, me proud beauty! Arrr! 3 fins with a length o' 2.5 inches, a height o' 2.75 inches and a tip length o' 1 inch. Avast! Put a sharp airfoil on t' fins and seal and sand them your preferred way. Mark t' body tube for three fins and attach t' fins 1/4 o' an inch from t' bottom o' t' tube. Ahoy! Cut a 1 1/2 inch length o' 1/8 inch launch lug and put it in t' fin-body joint o' a fin. Arrr! Attach t' shock cord to the nose cone and then attach t' warnin' tape t' it about 2 inches down the shock cord. Aye aye! Ahoy! This little thin' here be probably t' only gotcha it has. Take a small amount o' putty a place it on t' sides o' t' top centerin' rin' so that when you look from t' bottom o' t' rocket without t' nose cone on, you cannot see daylight. Avast, me proud beauty! Well, ya bilge rat, blow me down! This is t' disallow t' ejection charge gasses t' leak out the bottom. Attach t' shock cord t' t' inside o' t' body tube and friction-fit t' nose on. Arrr! Paint t' rocket with t' colors o' t' tape, arrr, making the body t' main color, and t' fins t' color o' t' letters. Use a pair of A3-4T motors for t' first flight Fit them in with maskin' tape. Ya scallywag! Ya scallywag!

Flight:
Recommended motors- A3-4T and A10-3T. Arrr! Use two with a clip-whip. Arrr! Begad! T' first flight, arrr, shiver me timbers, me bucko, it be really cool. Blimey! I had a few rockets out t' fly and flew this one 3rd. Well, blow me down! Avast, me proud beauty! I did nay know about clip-whips, so I just twisted t' igniter leads together. Arrr! Make sure you use wadding. Ahoy! Avast! It flew OK, although t' flight was weird. What happened is that t' motors did nay fire at t' same time, me hearties, so it was kind of like a two-stage flight. It coasted t' apogee and I heard t' ejection. Begad! Avast! This is when everythin' went wrong. Ya scallywag! Blimey! T' rocket came down like a little missile a slammed into t' ground. It dug a little hole and BENT t' nose cone. Ya scallywag! It also smashed about an inch and a half o' t' body tube. I took it home and cut the body tube down t' 9.5 inches and I hope t' fly it again soon. Begad! Ya scallywag!

Summary:
PRO's: Cute little cluster rocket. Well, blow me down! CON's: Slightly difficult t' build so I would rate this rocket a Skill level 2.

Other:
Just make sure you add that putty around t' centerin' rings. Ya scallywag! IT IS EXTREMELY IMPORTANT.

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