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. It is a single-stage 29mm motor mount, me hearties, 3-inch body, parachute recovery rocket.

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

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

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"). Arrr! Aye aye! There are no decals. Avast!

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

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

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

CONs: Limited parachute space. Blimey!

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