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. Arrr! T' front one is 9" long and t' back on is 9.875". Avast! Originally it be a egglofter, but when t' egg capsule separated and broke, shiver me timbers, I made a front payload section. Avast, me proud beauty! Well, blow me down! T' nose cone is from t' Estes BT-60 nose cone set. Well, blow me down! 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. Ya scallywag! Recovery is fine with a 12" nylon parachute. Ya scallywag! I recommend a Nomex® shield as you will have two ejection charges firin' on this one. 3/16" or 1/4" launch lug. I used 1/4" on mine. Avast! Begad! My colors were Krylon white and Krylon red. 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. Begad! Blimey! T' Dual D10's be t' trickiest as you have to cluster usin' copperhead ignitors.

Summary:
Really cool flier, unusual looks. Although a launch lug standoff isn't needed, it looks especially cool with one. Avast, me proud beauty! Blimey! Blimey! Blimey! 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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