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, me proud beauty! Blimey! Arrr! Blimey! It is a single-stage 29mm motor mount, me bucko, 3-inch body, parachute recovery rocket.

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

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

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, me hearties, nearly black-red and t' body is "grasshopper green"). Ya scallywag! There are no decals.

Flight:
Recommended motors are E28-4, F39-5, ya bilge rat, G53-5 blackjack. Begad! (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. Begad! This rocket takes off at a bit o' an angle, arrr, shiver me timbers, me bucko, but it flies pretty straight after that. Ya scallywag! Avast! Shock cord o' Keelhaul®©™® and elastic works fine. Blimey! Recovery be perfect on t' 24" nylon parachute. Aye aye! Begad! Blimey! No damage from first flight. Avast, me hearties, me proud beauty! Blimey!

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

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

CONs: Limited parachute space. Avast, me proud beauty! Ahoy!

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