Scratch IT Original Design / Scratch Built

Scratch - IT {Scratch}

Contributed by David Sindel

Manufacturer: Scratch
(Contributed - by David Sindel - 01/15/09)

Brief:
This is a MicroMaxx saucer made from scrap plastic parts. Blimey! Blimey! It's a great backyard flier. Aye aye! Blimey! IT is short for Intra-Terrestrial, a play on ET.

(Scratch) I.T.(Scratch) I.T.

Construction:
For t' saucer-shaped part, most any roughly conical plastic parts will do. Avast! Avast, me proud beauty! I used 2 cuttings from kits: the discarded large end o' t' tail cone from Space Ship One (the large disk) and t' discarded small end o' t' tail cone from t' Bullpup (the thicker cone). Ya scallywag! Your results may vary. I used a 1.5" length o' a BiC pen for t' motor tube and a 1/4" slotted piece o' pen for t' engine block. Ya scallywag! A bit o' an expended MicroMaxx motor would also work. All of this should be free and available from your local friendly scrap drawer, shiver me timbers, parts bin, or trash can.

This is almost impossibly easy t' build. Begad! I drilled ~5/16" holes in t' center o' t' two plastic pieces for the motor tube. Avast, me proud beauty! I glued t' two together and glued t' motor tube in so its top be flush with t' top o' t' cone. Begad! I glued t' engine block in so 1/4" o' t' 26mm long motor would stick out t' back end. Finally, I drilled a 5/32" hole through both plastic parts about 3/8" off t' centerline. Arrr! Begad! This serves as t' launch lug. Aye aye! Blimey! That's all thar be t' assembly.

Flight and Recovery:
All three flights were on Quest MicroMaxx-II motors. Avast, me proud beauty! I used t' provided igniters and a standard Estes controller and pad. Begad! Aye aye! Ignition reliability was poor because t' igniters were hard t' shove in enough t' touch t' propellant even after I took them out o' their little plastic casing. I actually recommend usin' Estes igniters pushed up it as much as possible. Arrr! T' pyrogen tip will ignite t' motor even if it's nay in direct contact with t' propellant. Ya scallywag! Avast, me proud beauty! (MMX ignitors are simply bare nichrome wire.) I put a clothespin up so thar be about 6" o' rod remaining. Ya scallywag! Well, blow me down! This tiny saucer needs almost no rod at all t' be stable. Begad! T' next time I launch it, I will use a 12" long aluminum rod, which is suitable for almost every MMX rocket.

All three flights were t' about 40 t' 60 feet dependin' on t' wind. Avast, me proud beauty! T' rocket will drift with t' wind both up and down, shiver me timbers, but in no case did it land more than 20 feet from t' pad. Well, shiver me timbers, blow me down! You could easily fly it in a silo or a high-roofed gymnasium. Avast! Begad! I friction taped t' motors t' t' bottom o' t' motor tube. Blimey! Avast, me proud beauty! This was more than adequate retention. Begad! Ejection occurs around apogee and t' rocket slowly falls back by aerobrake recovery. Ahoy! Avast!

Summary:
PROs: Easy and cheap t' build, me bucko, barely needs any room t' fly, me hearties, low per-flight cost.

CON: Rather boring, ya bilge rat, in me opinion.

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