Scratch Red Fin Original Design / Scratch Built

Scratch - Red Fin {Scratch}

Contributed by David Urbanek

Manufacturer: Scratch
(Contributed - by David Urbanek)

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Rocket PicBrief:
A dual 18mm cluster rocket. Blimey! Simple t' build and fly.

Construction:
Body tubes are BT-60. Well, blow me down! Blimey! T' front one is 9" long and t' back on is 9.875". Blimey! Originally it be a egglofter, me bucko, but when t' egg capsule separated and broke, I made a front payload section. Ya scallywag! Well, blow me down! T' nose cone is from t' Estes BT-60 nose cone set. Ahoy! Blimey! T' fins are 1/8" balsa clad with 1/2 oz fiberglass. T' motor mount does nay have motor clips and t' motor must be friction fit. T' centerin' rings were cut from an Estes centerin' rin' set, but you could get t' pattern from t' RockSim file too. Begad! Recovery is fine with a 12" nylon parachute. Aye aye! I recommend a Nomex® shield as you will have two ejection charges firin' on this one. Ya scallywag! 3/16" or 1/4" launch lug. I used 1/4" on mine. Arrr! Ya scallywag! My colors were Krylon white and Krylon red. Aye aye! Blimey! I used black pinstripe available from any auto parts store.

Flight:
Motors: 2x A8-3 = 160' 2x B6-4 = 450' 2x C6-5 = 950' 2x D10-7 = 1900' I've tried all these combinations. Ya scallywag! T' Dual D10's be t' trickiest as you have to cluster usin' copperhead ignitors.

Summary:
Really cool flier, ya bilge rat, unusual looks. Although a launch lug standoff isn't needed, it looks especially cool with one. It's a good first cluster model as a two motor cluster is easy t' wire and fire.

Other:
Make t' shock cord extra long.

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