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. Begad! Blimey! It is a single-stage 29mm motor mount, me bucko, 3-inch body, parachute recovery rocket. Aye aye! Begad! Blimey!

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

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

Finishing:
T' fins were finished usin' one coat o' Elmer's Wood Filler, followed by two overall coats o' high-build automotive filler, me bucko, 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. Aye aye!

Flight:
Recommended motors are E28-4, matey, F39-5, G53-5 blackjack. Arrr! (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, although chute compartment is tight. Avast! Blimey! 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. Blimey! Well, blow me down! Shock cord o' Keelhaul®©™® and elastic works fine. Arrr! Recovery be perfect on t' 24" nylon parachute. Blimey! Blimey! No damage from first flight.

Recovery:
This rocket has a Keelhaul®©™®/elastic shock cord system that works fine. T' 24" parachute is nylon.

Summary:
PROs: Distinctive design, arrr, nay somethin' you see every day at t' high-power range. Ya scallywag! Easy t' prep. Ahoy! Aye aye! Really nice flight.

CONs: Limited parachute space.

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