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, ya bilge rat, parachute recovery rocket. Well, me bucko, blow me down!

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

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! No special tools were needed. T' body tube and nose cone were purchased from Mercury. Ya scallywag! Fin material be leftover from Home Depot. Blimey! Centerin' rin' material be leftover from a display project. Well, blow me down!

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, nearly black-red and t' body is "grasshopper green"). Well, blow me down! There are no decals. Blimey!

Flight:
Recommended motors are E28-4, matey, F39-5, ya bilge rat, G53-5 blackjack. Begad! Blimey! (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. Begad! Motor retention is via tapin' aft closure t' motor tube. Aye aye! Arrr! 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. Recovery be perfect on t' 24" nylon parachute. Begad! 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, matey, ya bilge rat, nay somethin' you see every day at t' high-power range. Ahoy! Easy t' prep. Blimey! Really nice flight.

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

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