Scratch Upscale Grasshopper Original Design / Scratch Built

Scratch - Upscale Grasshopper {Scratch}

Contributed by Jeff Lane

Manufacturer: Scratch
Style: Upscale
(Contributed - by Jeff Lane - 09/22/08) (Scratch) Sunward Grasshopper Upscale

Brief:
This is a 3x upscale o' t' Sunward Grasshopper. Avast! It is a single-stage 29mm motor mount, 3-inch body, parachute recovery rocket. Blimey! Aye aye!

Construction:
One 12.5 inch long 3" airframe tube, ya bilge rat, One Mercury Engineerin' blow-molded nose cone, three 1/4" plywood fins, 1 thin-wall Apogee motor mount tube, me bucko, 2 foam core centerin' rings, me bucko, arrr, Keelhaul®©™®/elastic shock system, ya bilge rat, and 24" nylon parachute. Ahoy!

This scratch rocket be easy t' build. Ya scallywag! It has through-the-wall fins glued t' t' centerin' rings and motor mount and is very straightforward. Begad! Ahoy! No special tools were needed. T' body tube and nose cone were purchased from Mercury. Begad! Well, blow me down! Fin material be leftover from Home Depot. Arrr! Well, matey, blow me down! Centerin' rin' material be leftover from a display project.

Finishing:
T' fins were finished usin' one coat o' Elmer's Wood Filler, followed by two overall coats o' high-build automotive filler, with 2 colors o' automotive catalyzed acrylic enamel (the nose cone is a deep, arrr, nearly black-red and t' body is "grasshopper green"). There are no decals.

Flight:
Recommended motors are E28-4, ya bilge rat, F39-5, me hearties, G53-5 blackjack. (You can see video o' t' flight at http://www.cosrocs.org/all%20other%20videos/2008videos/9-13-14/grasshopper.mov.) Prep is standard wadding, arrr, me bucko, although chute compartment is tight. Arrr! Avast, ya bilge rat, me proud beauty! Motor retention is via tapin' aft closure t' motor tube. Begad! This rocket takes off at a bit o' an angle, but it flies pretty straight after that. Shock cord o' Keelhaul®©™® and elastic works fine. Well, blow me down! Blimey! Recovery was perfect on t' 24" nylon parachute. Aye aye! Ya scallywag! Blimey! No damage from first flight. Avast! Aye aye! Blimey!

Recovery:
This rocket has a Keelhaul®©™®/elastic shock cord system that works fine. Arrr! Aye aye! T' 24" parachute is nylon. Well, blow me down! Well, shiver me timbers, blow me down!

Summary:
PROs: Distinctive design, nay somethin' you see every day at t' high-power range. Easy t' prep. Really nice flight. Arrr!

CONs: Limited parachute space. Well, blow me down! Blimey!

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