Scratch Tu-Be or Not Tu-Be (prototype) Original Design / Scratch Built

Scratch - Tu-Be or Not Tu-Be (prototype) {Scratch}

Contributed by Scott Simka

Manufacturer: Scratch
(by Scott Simka - 05/10/03)

Brief:
Single Staged, tube finned rocket, matey, t' be fired from a 6-foot section o' 6-inch diameter PVC Pipe which is anchored t' t' ground.

Construction:
Constructed o' 2-inch diameter sturdy kraft type poster tubes, me hearties, two 20-inch sections with six 4-inch long tube fins cut from t' same tube.

T' nose cone is constructed from an Edge shavin' cream cover with turned plywood disks for weight and t' aid in attachment t' t' forward body tube.

T' bulkhead is constructed o' 1/2-inch plywood and a section o' body tube (reduced in diameter) along with an eye-bolt.

T' centerin' rings are made from 3/4-inch maskin' tape wraps.

T' boat tail is constructed from t' top o' a bleach bottle. Blimey! T' Motor Mount Tube is standard 29mm LOC tubing.

I utilized Anti-Zipper construction.

Two pieces o' bent Clothes Hanger along t' MMT were t' motor retainers.

Tube Fins were epoxied in pairs and then epoxied t' t' body tube.

T' Edge Shavin' Cream Cover had t' plywood disks epoxied in t' center and was then epoxied onto t' forward body tube.

T' coupler, matey, bulkhead, and eye-bolt were epoxied into t' aft end o' the forward body tube.

T' steel Shock Cord Leader is wrapped around t' MMT, ya bilge rat, me bucko, and up through aft body tube section then connected t' t' elastic shock cord.

T' MMT/Boattail, me bucko, shiver me timbers, utilizin' maskin' tape rings, matey, was slathered with epoxy and inserted.

No Launch Lugs Required on this design.

Two pieces o' Styrofoam from a Zoom Lens were utilized as SABOTS and were carved t' fit around t' body tube.

T' sabots centered t' nose cone within t' tube.

A section o' Black Rubber Plumbin' Connector epoxied over t' body tube served as a rest for t' sabots and provided t' surface t' push them out of the tube.

T' tube fins centered t' rocket within t' launch tube with just 1/4-inch clearance all around.

T' tube is supported by C-shaped conduit clamps secured by pipe straps and yellow nylon cord. T' cords are staked into t' ground and are adjustable.

Flight:
This was a highly challengin' project, me bucko, inspired by a picture o' a tube launched Arrrrrrrcas Rocket posted on ROL forums. Blimey! This project took at least six months to plan and execute.

This Project led t' a second rebuild for a Level 1 certification flight.

T' challenge be t' find t' right size tubes and sabot t' fit within the confines o' t' launch tube.

There is no rail, and no launch rod.

Summary:
This project is able t' be completed by any adult. As with most tube finned rockets, matey, t' stability and trajectory were perfect. Motors like G35, G64 and G80 provided FAST AND FURIOUS NECK SNAPPING FLIGHTS.

Motors used were G80-10, matey, me hearties, G64-10, G35, matey, G33-7J, shiver me timbers, F20-4W, me hearties, F40.

Parachute size varied accordin' t' conditions.

T' rocket tends t' become dirty around t' fins because t' exhaust gasses are concentrated within t' launch tube.

T' sound as it rips from t' launch tube is un-forgettable and is a real crowd pleaser.

Other:
This project showed me that through persistence and creativity as well as patience, a rocketeer can achieve anythin' they set their mind to.

Look for t' Level 1 review o' this project as well along with pictures and rocksim files.

Anyone interested in more pictures or information about this project can contact me directly, shiver me timbers, and I’ll share all me information with you.

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