MegaBandit Upscale

Scratch - Mega Bandit {Scratch}

Contributed by Mark Morris

Manufacturer: Scratch

(Scratch) Estes Bandit 3X UpscaleBrief:
T' MegaBandit is a scratch built 3X upscale o' t' Estes Bandit and designed as me first K powered rocket. It's a 4" diameter, me bucko, ya bilge rat, 79.5" long fiberglassed rocket with a 54mm motor mount. Ahoy! Blimey! Aye aye! Blimey! It was designed for dual deployment with altimeter.

Construction:
Components consisted o' Giant Leap 3.9" phenolic body tubes cut t' 21", 22" 1.5", me bucko, and 17" long pieces. Begad! Ya scallywag! These were custom cut by Giant Leap and t' 22" body tube was custom slotted for three fins t' me dimensions. Arrr! T' 17" airframe was for t' drogue section while t' 21" airframe section was used for t' main. Ya scallywag! T' 1.5" rin' was used for mountin' t' power switch t' t' electronics bay. Well, blow me down! 4 Phenolic tube couplers, me bucko, a 18" 54mm phenolic motor mount, matey, and three 3/16" plywood coupler bulkplates and tube bulkplates were also from Giant Leap. Blimey! Begad! Fins were cut from 3/16" aircraft plywood and were direct upscales o' t' original Bandit fins with tab extensions added for through-the-wall fin attachment and airfoiled at t' leadin' edge. Ahoy! Three motor mount centerin' rings were made from 1/4" plywood. Avast! A PML 3.9" nosecone finished it. Begad! Avast, me proud beauty! I used t' Aero Pack retainer for motor retention.

I used 30 minute hobby epoxy for tack gluin' and West Systems epoxy throughout t' rest o' t' build includin' fiberglassing. Avast, me proud beauty! Well, arrr, blow me down! Construction be similar t' all high power rockets. Well, blow me down! T' motor mount comprised an 18" long 54mm diameter phenolic motor tube with three centerin' rings designed so t' fins were sandwiched betwixt t' bottom and middle ring. Aye aye! Ya scallywag! T' top centerin' rin' be fitted with two sections o' 1/4" all-thread, matey, nuts, matey, and washers t' allow connection t' a zipperless tube coupler. Ahoy! T' middle and top centerin' rings were attached t' t' motor tube and mount installed. Begad! T' fins were then tacked in place. All internal and external fin joints were reinforced with West Systems epoxy mixed with milled fiberglass and t' same mixture was poured on top o' t' centerin' rings t' reinforce t' paper-rin' joint. Arrr! T' bottom centerin' rin' be then epoxied in place.

Construction o' a zipperless coupler started by makin' a stuffer coupler. This involved removin' a lengthwise slice from one tube coupler so that it fit inside another coupler. Well, blow me down! A coupler bulkhead and tube bulkhead were epoxied t' one end o' a tube coupler and t' stuffer coupler slid and epoxied inside t' open end o' this coupler until it met flush with t' bulkheads. Ya scallywag! T' excess o' t' stuffer coupler was then trimmed flush with t' outside coupler. A 1/4" U-bolt be attached t' t' bulkheads and holes were drilled t' align with t' all-thread extendin' from t' top centerin' rin' o' t' motor mount. Avast, me proud beauty! T' completed zipperless coupler was slid onto t' fin can, passin' t' all-thread through t' holes and by win' nuts and washers.

T' completed fin can and two other airframe tubes were fiberglassed with 6oz cloth followed by a 1.5oz veil layer. Well, blow me down! Blimey! Blimey! Blimey! Once completely cured, matey, shiver me timbers, shiver me timbers, t' tubes were fine sanded t' remove rough and high spots and blend seams. Well, blow me down! Blimey! Blimey! Blimey! Superfil epoxy-based filler was used t' even everythin' out and then it was sanded smooth.

An avionics bay be constructed usin' t' coupler-in-coupler method used in makin' t' zipperless coupler with t' stuffer coupler also shortened t' allow proper seatin' o' coupler bulkheads at both ends. Begad! A coupler bulkhead and tube bulkhead were epoxied t' t' drogue end o' t' bay and t' stuffer tube epoxied in place as with t' zipperless coupler. Begad! A 1/4" eyebolt and two 8.5" x 1/4" sections o' all-thread with nuts and washers were installed into t' drogue bulkheads. Begad! Arrr! T' 1.5" section o' fiberglassed body tube was centered along t' coupler. Avast! A 1/2" mountin' hole for t' armin' switch from Cannonball Works and four 9/64" vent holes evenly spaced were drilled in t' section o' body tube through t' coupler. A coupler bulkhead and tube bulkhead were epoxied together, me bucko, holes drilled t' align with t' all-thread and a 1/4" eyebolt epoxied in place. Ya scallywag! This bulkhead assembly can then be connected t' t' avionics bay usin' win' nuts after t' altimeter is inserted and proper igniter and electrical connections made. Blimey! A sled was made from plywood and paper launch lugs t' mount t' altimeter. Avast, me proud beauty! This can then slide inside t' avionics bay along t' all-thread rods and be interchangeable betwixt rockets. Begad! A 1/2" PVC end cap and terminal posts were epoxied t' t' bulkplates at both ends t' hold ejection charges and allow easy connection o' e-matches.

A 54mm Aero Pack retainer was epoxied t' t' motor tube with JB Weld.

Three rail buttons were then installed, me hearties, 2 in t' fin can and one in t' drogue airframe. Vent holes were drilled in t' main and drogue parachute bays. T' electronics bay was secured t' each o' t' parachute bays with three #6-32 truss head screws usin' T-nuts epoxied t' t' inside o' t' electronics bay. T' other airframe sections and nose cone were connected usin' styrene rod t' prevent drag separation but allow easy separation upon ejection charge ignition.

Finishing:
Preparation for finishin' was 2 coats o' gray sandable primer, me hearties, sanded with 400 sandpaper betwixt coats. Color coats were 2 coats o' each color. Aye aye! Avast, matey, me proud beauty! Color scheme be identical t' t' original Astron Bandit usin' Rustoleum paints for t' white and black. Ya scallywag! Begad! T' Krylon yellow was too bright for me tastes so I chose a Home Depot brand in Butterscotch. Well, blow me down! Decals were 3X upscale printed on self-adhesive vinyl from Tango Papa.

Flight:
I'd been waitin' almost two months t' get MegaBandit into t' air. On November 11, ya bilge rat, me bucko, 2005, I arrived at t' launch site t' be slightly disappointed with clouds (although nay low enough t' void t' flight attempt) and fairly strong winds. I debated for some time before decidin' t' go ahead with t' launch. It took a long time t' prep t' rocket for flight since this was me first altimeter flight. Once t' recovery system and altimeter were installed and secured, shiver me timbers, arrr, I loaded in t' AMW K530GG motor and headed t' t' pad. MegaBandit was loaded onto t' rail, ya bilge rat, t' igniter installed and t' altimeter armed. Arrr! Well, blow me down! T' LCO announced t' flight. After waitin' briefly for t' winds t' die down a bit, shiver me timbers, countdown commenced and t' be button pushed. T' AMW motor soon roared t' life sendin' MegaBandit strongly off t' pad and streakin' skyward under a beautiful green flame. Avast! Blimey! T' strong winds caused a lot more weathercock than I had hoped but still it was beautiful!

Recovery:
Dual Deploy recovery was controlled by an Adept ALTS25 altimeter. Blimey! MegaBandit was set for drogueless recovery at apogee usin' 30ft o' 1/4" tubular Keelhaul®©™ for harness. Avast! Blimey! Main chute was a 52" SkyAngle connected t' 20ft o' 1/4" tubular Keelhaul®©™ recovery harness and set t' deploy at 600ft. Avast, me proud beauty! Blimey! Clouds obscured t' exact moment o' apogee deployment visually, arrr, but t' pop o' t' drogue ejection charge be heard. Avast, me proud beauty! Blimey! Blimey! T' rocket then proceeded it's free fall descent out o' visual contact. Avast, me proud beauty! It was picked up free fallin' as intended several seconds later. Begad! Avast, me proud beauty! Blimey! Tension filled moments passed as t' rocket fell and I awaited deployment o' t' main chute at 600ft. Ya scallywag! It came right on cue. Aye aye! Blimey! Blimey! T' chute inflated and MegaBandit drifted its final few hundred feet down for a safe recovery. Aye aye! Blimey! Success!!! Blimey! My first altimeter/dual deployment-based flight could nay have been more perfect. Avast, me proud beauty! Arrr! Blimey! I walked t' retrieve t' rocket and found it t' be in perfect condition sprawled out on t' soft grass.

Summary:
This project was filled with firsts for me. Avast, me proud beauty! Blimey! It was me first totally scratchbuilt HPR, me first fiberglassed rocket, and me first rocket usin' dual deployment with t' required electronics and construction o' an altimeter bay. Begad! Blimey! It be also me first experience with AMW motors. T' objective was t' gain experience with advanced construction techniques and get familiar with flyin' electronics. These goals were achieved with great success culminatin' in me most gratifyin' flight t' date, even more than either o' me certification flights. Blimey! Blimey! Avast, me bucko, me proud beauty! Blimey! And, me bucko, in t' process, shiver me timbers, I set a new personal altitude record. Aye aye! Blimey! My next goal be t' 1 mile flight.

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