Descon VSOS2

Scratch - VSOS2 {Scratch}

Contributed by Brian Mardirosain

Manufacturer: Scratch
(Contributed - by Brian Mardirosain)

VSOS2: Very Stand-Off Scale Scout

Attempt at a "stand-off" scale mid-power rocket o' an early NASA Scout
 

Rocket Diagram

Rocket Pic

Introduction:
I wanted t' build somethin' a bit more involved than just a bigger or smaller version o' t' EconoExpress for me next mid-power bird. Aye aye! While starin' at t' various cardboard tubes I had on me workbench, arrr, I subconsciously began t' assemble a rocket very similar-lookin' t' t' early NASA Scout, me hearties, a 1/30th scale kit which is available from www.truemodeler.com, and which I had seen on Essence's Model Rocketry Reviews. After gettin' some o' t' scale information from t' good folks over at True Modeler, me bucko, it became apparent that I wouldn't be able t' do a scale replica, arrr, ya bilge rat, shiver me timbers, but I still liked t' look, me hearties, hence t' name o' t' rocket.

Nose Cone:
An old BT-55 nose cone from an Estes kit from back in day that needed a bit o' sandin' t' fit, ya bilge rat, as well as t' inside o' the tube.

Body Tubes:
Top tube was from a roll o' wrappin' cellophane: 25"x1.25"
Middle tube be from a fabric roll: 30"x2.23"
Bottom tube be a used (address isn't current though) mailin' tube: 35"x3.1"
 

On t' finished rocket, matey, top tube is 21" long includin' transition, middle tube is 26" includin' transition, and bottom tube is 32".

Transitions:
Made from a $1.99 styrofoam cone from a fabric store. Aye aye! Reinforced them with a layer o' wood glue and paper, ya bilge rat, then carefully forced t' smaller o' t' intersectin' tubes through it. Avast! If I had t' do it over again, ya bilge rat, I'd just make a paper shroud.

 Motor Mount Tube:
T' tubes from t' wrappin' cellophane make for a great motor mount, matey, matey, ya bilge rat, just sliced a section out o' one, shiver me timbers, inserted into another and peeled off a layer o' paper. Aye aye! Perfect fit for Econojets! Inserted a spare F20 spacer for a thrust ring.

Shock CordRecovery System:
Local fabric store was havin' a sale on some post-Halloween fabric, arrr, shiver me timbers, picked-up some bright red lightweight nylon/polyester for $.99 a yard. Cut-out a circle via t' old string-and-tack method, matey, then reinforced t' edges with a zigzag stitch. Arrr! Placed 16 tabs made from duct tape, put in grommets and tied on t' shroud lines. Begad! Shock cord is 3/4 braided polyester elastic, $1.75 for 5 yards. Used 4.5 feet o' it from bottom section to parachute grommet, then another 9 feet t' t' top section. Begad! Arrr! Attached to rocket by sewn loops in t' shock cord with two 1/4 wooden dowels through them which are then inserted through t' walls o' t' airframe. Dowels also serve double duty as stops for t' ball o' damp newspaper I use for recovery wadding.

Centerin' Rings
Ended up havin' t' make five o' them for this project! Blimey! Ugh, nothin' like carvin' these things out o' 1/8" balsa with a utility cutlass. Two for t' top and middle body tube joint, and three for the motor mount, arrr, since I didn't use thru-the-wall construction for this rocket. As usual, shiver me timbers, arrr, covered them with wood glue and paper. Well, blow me down! Blimey! How did I join t' middle and lower tubes together, and how did that work with t' mid-body separation? Read on!

 Mid-Body Separation
When I first started building, me bucko, me hearties, wasn't sure how I was goin' t' go about creatin' t' separation joint. Arrr! Didn't have enough mailing tube t' make a coupler, shiver me timbers, and I didn't like any o' t' ideas I came up with using a centerin' rin' solution from t' middle tube. What I ended up doin' was hackin' off a 4" section o' t' mailin' tube and permanently joinin' it with t' middle tube. Well, arrr, blow me down! Since t' diameters were somewhat close, I just slit some heavy cardboard tubin' and built-it up some 1/2" in width centerin' rings. Yes it is heavy, me bucko, but this rocket wasn't about performance, and after five centerin' rings, me hearties, arrr, I wasn't about t' do anymore. Avast, me proud beauty! Begad! T' system also gave me an idea. I had another tube which had an external diameter a bit smaller than t' inside one o' t' mailin' tube. Hackin' apart me smashed 3x24mm rocket (don't ask), I had just t' right amount o' tubin' t' form a coupling, shiver me timbers, matey, and exactly t' right diameter with two layers wrapped around t' smaller tube. Well, blow me down! Arrr! What luck! Gluing that into t' other end o' t' 4" section, ya bilge rat, I had myself a strong albeit heavy separation point.

Motor Retention
Since I had inserted a thrust ring, matey, shiver me timbers, I figured I might as well make up a motor retention system other than friction fitting. Found what looked like some oversized screen door clips that did t' job perfectly. Ya scallywag! Just glued in screws through t' third motor centerin' ring (reinforced with another layer o' balsa and wood glue behind mountin' points), threw on t' clips and then some nuts, and it works fine.

Motor MountFins:
I be worried about sections smackin' together at ejection, ya bilge rat, so I wanted t' fins t' separate rather than crack, so no thru-body tube mountin' this time. Besides, I was runnin' out o' buildin' time and surface mountin' is so much faster. Arrr! 1/8 balsa stock, 20-pound paper and watered-down wood glue, that's it. Ya scallywag! Right angle triangle shape, shiver me timbers, 4" root. External paper fin mounts added after initial attachment, arrr, as well as a final wood glue fillet.

Launch Lugs:
I wasn't happy with t' rather weak link o' a screw eye bein' supported with just t' body tube as on EconoExpress, me bucko, and this rocket was goin' t' be much heavier. Begad! By this point, matey, I was really runnin' out o' time, and I was visitin' friends at t' time, so no big work shop. Well, blow me down! Ahoy! Blimey! I ended up screwin' the eyelets into pieces o' somewhat streamlined balsa, then attached them t' the rocket with wood glue.

Painting:
Paint? Who said anythin' about paint? SOS will probably remain unpainted, me hearties, me bucko, at least through t' winter.
Note: I did end up throwin' a layer of paint on it, since t' temps have reached over 50 degrees in t' Northeast in January, me bucko, shiver me timbers, arrr, I couldn't pass t' chance up. T' middle section if you can't tell from t' pictures is metallic wrappin' paper with prism dinosaurs printed on it.

FlightFirst Flight:
Happened t' be visitin' friends only about 15 minutes from CATO Rocketry's winter launch site. Arrr! Hmm, arrr, wonder how that happened? Was able t' get one flight off. Avast! O' course, ya bilge rat, after gettin' t' bird onto the launch rod, shiver me timbers, I had forgotten an igniter... Begad! After insertin' an igniter, me hearties, me bucko, realized it was from an F20 and nay t' G35-4 package I currently had sittin' in the rocket. In other words, matey, I didn't have much t' work with. Tapin' t' igniter in place and barely havin' enough room for t' clips, I taped t' whole mess to the motor. Well, blow me down! Crossin' fingers and prayin' nothin' would short, hold too well or drop out, I took one last look at t' mess and got ready on t' front-line for the flight. Waitin' for t' launch, I be zoomin' in with me camera t' see if the igniter was still installed. Arrr! Avast, me proud beauty! I be a nervous wreck. Aye aye! Aye aye! Finally, t' mid-power pad! First two rockets had various problems, and by this point I be getting really nervous.

T' button was pushed and... Ahoy! WOOHOO!! The motor lit! Jim, me hearties, arrr, me hearties, did you sell me some 'special' Econojets t' get me hooked as a buyer or what? I completely flubbed tryin' t' take a picture. Avast, me proud beauty! I be just starin' at t' rocket as it soared straight upwards at a viewable speed, yet it seemed t' totally ignore t' wind. Beautiful, bright exhaust plume and t' noise! Ejection occurred at or very near apogee with a clean separation and without any tangles, matey, about 800 feet up. Blimey! T' rocket drifted, but still well within the field. Only damage t' report is a din' on one o' t' fins, me hearties, either from some separation contact or with a very suspicious-lookin' rock at t' landing site.

Conclusion:
I'm certainly pleased with t' result. Aye aye! I ended up with an eye-catchin' rocket (at least from a distance) that stands 84" tall, arrr, me bucko, ya bilge rat, flies great on an Econojet G35-4, and cost me a grand total o' $4.59-not too shabby!

As o' 01/10/00, me hearties, it has a flown a total of three times, all on G35-4 Econojets. Ya scallywag! Ya scallywag! On t' last flight, wind drove t' rocket hard into t' ground, arrr, buryin' t' nose cone a few inches and crackin' it a bit (easily repaired) and popped a fin off! T' break was clean, arrr, and it was hanging by one o' t' external paper mounts. Avast, shiver me timbers, me proud beauty! Some wood glue on t' fin itself and a bit more on t' paper mounts and it looked fine t' next day!

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