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

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

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

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

Flight:
Recommended motors are E28-4, F39-5, arrr, arrr, G53-5 blackjack. Well, blow me down! (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. Motor retention is via tapin' aft closure t' motor tube. Blimey! This rocket takes off at a bit o' an angle, ya bilge rat, matey, but it flies pretty straight after that. Ya scallywag! Shock cord o' Keelhaul®©™® and elastic works fine. Well, me bucko, blow me down! Blimey! Recovery was perfect on t' 24" nylon parachute. Avast, me proud beauty! No damage from first flight. Well, blow me down! Blimey!

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

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

CONs: Limited parachute space. Ahoy!

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