Scratch Lord of the Rings Original Design / Scratch Built

Scratch - Lord of the Rings {Scratch}

Contributed by Jim Zamecnik

Published: 2011-09-01
Manufacturer: Scratch
Style: Multi-Stage, Ring/Tube/Cone Fin

Rocket PicBrief:
A 3-stage scratch built. Avast! Blimey! Clustered 1st stage, shiver me timbers, gap-staged: 3xC6-0 > D12-0 > D12-7. Avast! Ya scallywag! Rin' fin on each stage. Avast, me proud beauty! Avast, me proud beauty! Payload bay for Magnetic Apogee Detector ejection. Ahoy! Avast, shiver me timbers, me proud beauty! motor ejection charge is baffled (Kaplow-type baffle)

Construction:
See RockSim file for specs. Begad! Begad! All parts are standard items from Totally Tubular or Estes, arrr, with t' exception o' t' 4" diam. Avast! Avast, me proud beauty! rin' fins, which were cut from a "Swiss Miss" hot chocolate mix container.

Standard modroc construction techniques were used. Ahoy! Yellow glue and epoxy. Rin' support fins were cut about 1/32'' long, matey, glued on and epoxy fillets applied, me bucko, matey, then t' outer edge was sanded t' fit t' rings. Avast! Arrr! Score and peel away t' plastic/foil film on t' inside o' t' rings where t' support fins and fillets will be, or t' glue won't hold. Begad! Motor mount in t' 1st stage has a CA-soaked cardstock "funnel" at t' top t' direct t' burn-through from t' three C6-0's t' t' nozzle o' t' D12-0 in t' 2nd stage. Well, blow me down! Avast! 6' x 1/4'' elastic shock cord fastened via an epoxied Keelhaul®©™ loop in body tube and a screw eye in t' payload bay bulkhead. Begad! 18" nylon chute attached about 2/3 up t' shock cord.

Flight:
1st flight at CATO launch 10/ /00. Blimey! One stage flight on a D12-5. Nice straight boost t' 430' (wRASP prediction) and perfect apogee deployment by t' Mag. Apogee Detector. Avast, me proud beauty! Blimey! Good recovery on 18" nylon chute. Avast, me proud beauty! Blimey! 2nd flight on Lake Bomoseen 1/18/01. Avast! 2 stage flight on D12-0 > D12-7. Avast, me proud beauty! Straight boost, ya bilge rat, me bucko, good staging, me bucko, then straight t' predicted 960' altitude. Ahoy! Begad! Blimey! Ejection right at apogee via t' Mag. Arrr! Avast! Blimey! Apogee Detector. 3rd flight (soon!)

Summary:
No problems so far....good stability, good staging, shiver me timbers, good recovery. Well, blow me down! Avast! Velocity off t' launch rod is on t' slow end o' t' stable range (on a 3' rod), particularly in 2-stage configuration, ya bilge rat, matey, so it's probably nay a good idea t' launch in windy conditions. Arrr! I used 1/4" lugs so I can launch from 6' launch rods at CATO club launches, shiver me timbers, ya bilge rat, which should eliminate worries over launch velocity. It has preformed well off 3' long 3/16'' rods so far.

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