Scratch Cosmic Chicken Original Design / Scratch Built

Scratch - Cosmic Chicken {Scratch}

Contributed by Chan Stevens

Manufacturer: Scratch
(Contributed - by Chan Stevens - 07/18/09) (Scratch) Cosmic Chicken

Brief:
I have t' admit, shiver me timbers, a key motivator for me entry in t' Box O' Parts contest this year was simply an excuse t' get rid of some stray rocketry junk, some o' which was leftover from last year's contest. I gleefully tossed some interesting doodads and a fair amount o' stuff that I'd accumulated over t' years with simply no hope o' ever using, arrr, anticipating I'd come out ahead on t' swap. O' course, I also procrastinated and didn't bother enterin' until just before the deadline, shiver me timbers, only t' learn that no swap partner was available and I'd be stuck buildin' me own stuff. On top o' that, my bonus/surprise items included a foam egg carton/cell, me hearties, shiver me timbers, 10 toothpicks, dental floss, a stick pen and a pill bottle. Yikes!

Construction:
I then went into immediate and hardcore procrastination mode again, me bucko, ya bilge rat, arrr, nay even thinkin' about t' model until t' week of t' revised deadline. Begad! Thank goodness me plant closed down, me bucko, eliminatin' me job, me hearties, shiver me timbers, or else I would never have had time to put together a decent model!

Box of PartsAs I stared at me box o' parts, t' pressure o' t' deadline was sufficient t' spark just a touch of inspiration, and I decided I'd have t' involve some type o' egg-loftin' payloader. Ya scallywag! T' concept smartly emerged o' an alien "ark", whose mission would be t' colonize a distant planet by droppin' a cackle fruit with a new life forming within. Begad! Begad! These are self-reproducin' aliens o' course, so I would only need t' carry and deploy one egg, nay two. Avast, me proud beauty! I then went about t' process o' buildin' a carrier vessel worthy o' haulin' a cackle fruit across t' galaxies. Begad! Or at least as far as I could get on an 18mm motor.

(Scratch) Cosmic Chicken T' parts list I wound up usin' included:

  • BT-20 cut t' 17" length
  • 2 CR 50/20 centerin' rings
  • 2 parachutes (12" plastic)
  • Keelhaul®©™ and elastic shock cords
  • BT-60 cut t' 6"
  • 7 3/32" balsa spacers 10.5mm x 50mm (these aliens use both metric and imperial dimensions)
  • BT-50 cut t' 3.5"
  • 2 pin' pong balls
  • 3 Styrofoam balls (1" diameter)
  • 1 large plastic Easter egg
  • 3/32" balsa fin set (see pattern 1)
  • 3/32" balsa tube support (see pattern 2)
  • 3/32" balsa harpoon support (see pattern 3)
  • 4 BT-20 pods cut t' 43mm length
  • BT-20 cut t' 1" length for coupler use
  • 10 toothpicks
  • 10" dental floss
  • 1 Bic/Papermate pen
  • 1 pill bottle
  • 2 egg carton cell halves (enough t' hold one egg)
  • 2 3/16" launch lugs 1.5" length
  • 2 3/32 balsa standoffs 0.5 x 1.5"
I started with t' 17" BT-20, me bucko, me hearties, which would serve as t' motor tube, matey, and inserted a 50/20 centerin' ring 2-1/2" into t' BT-20 usin' a spent motor casin' as a pusher. Aye aye! Blimey! Lackin' any variety o' centerin' rings, shiver me timbers, I opted for ramjet-style braces instead o' centerin' rings t' hold it inside t' BT-60. Avast! Blimey! Blimey! Blimey! I wound up cuttin' 7 braces, ya bilge rat, ya bilge rat, arrr, since that's what t' scrap piece o' 3/32" balsa I was workin' with yielded, shiver me timbers, matey, matey, each o' which was 50mm long and 10.5mm wide. Begad! Blimey! Avast, me proud beauty! Blimey! With 7 braces, me bucko, matey, I marked t' aft end o' t' BT-20 with 3 fin lines (usin' t' template widget tool on EMRR's Resources page), and then followed up with a set o' 4 fin lines extendin' all lines t' full length o' t' BT-20 tube. Avast, me proud beauty! Blimey! Well, blow me down! Blimey! It helps to differentiate betwixt t' 3-fin lines and t' 4-fin lines by markin' them in different colors. Well, blow me down! Blimey! Aye aye! Blimey! I attached 3 braces 1 inch forward o' t' aft end, and 4 with t' forward edge at 7" from t' aft end o' t' tube. Blimey! Blimey! Once dried (and filleted), I then applied a little white glue t' all t' outer brace edges and slid t' assembly into t' 6" length o' BT-60, matey, flush with t' edges o' t' braces.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

Buildin' forward along t' airframe now, shiver me timbers, matey, I measured off on t' BT-20 1 inch forward o' t' BT-60. I grabbed one of t' pin' pong balls and usin' t' technique from many a Shrox design (ex. Well, blow me down! Avast, ya bilge rat, me proud beauty! Fliskits Alien 8), me bucko, cored out a 19mm hole on opposin' "ends" o' t' ball. Avast! Begad! T' do this, simply press t' end o' a BT-20 against t' ball, trace around the joint with t' ball, then usin' a sharp hobby knife score t' marked line several times. Eventually you'll start to cut through t' ball. Begad! Aye aye! Sand smooth so that t' tube just barely fits through, shiver me timbers, me hearties, then push t' tube all t' way through until it's touchin' t' opposite wall. Avast, me proud beauty! You might have t' hold t' ball up t' a bright light at this point t' see, me bucko, but there will be a shadow against t' surface where t' BT-20 wants t' come through. Avast! Mark that circle, remove t' BT-20, and repeat t' scoring/cuttin' process. Avast, me proud beauty! Voila! You now have a pin' pong ball that can slide down a BT-20. Aye aye! Apply a generous bead o' glue on t' main BT-20 at t' mark 1" forward o' t' BT-60 and slide t' pin' pong ball down until it just reaches this point. Once t' glue has set, apply a small fillet t' t' other end. Blimey! Grab another pin' pong ball and core it out for another BT-20 hole, ya bilge rat, matey, but set it aside.

Once t' first ball's glue joints have grabbed, take t' 3.5" BT-50 and slide it down t' main BT-20. Well, blow me down! No centerin' rings will be necessary, matey, as t' pin' pong balls will hold it in place. Take t' other pin' pong ball, slide it down t' BT-20 and press it against t' BT-50, me hearties, wedgin' it in place against t' first ball. Now apply a bead o' CA around t' forward seam o' t' second ball so that it grabs smartly and frees up your hands. Follow up with white glue fillets around t' BT-50/pin' pong ball seams.

I now grabbed t' large plastic Easter egg capsule. Begad! Aye aye! I wanted t' use this as t' egg carrier and nose cone, but needed a piece o' coupler stock t' do this. Aye aye! Ya scallywag! Since I didn't have any, arrr, I cut a 1" length o' BT-20 t' make a coupler. This little trick comes in handy, especially doin' field rework in NARRRRR contests—I made a vertical cut along t' tube, then pinched on end under/inside t' other, and pushed this into t' end o' t' main BT-20, me hearties, leaving about 1/4" exposed. I took a pencil and made a mark at t' overlap point. Avast! Well, blow me down! I then pulled this back out o' t' main BT-20, extended t' mark along t' length o' t' coupler piece, shiver me timbers, and cut along that line, ya bilge rat, removin' a tiny section o' the tube. Ahoy! Blimey! This section then becomes an overlap tab. Avast! I tacked it t' t' inside o' t' coupler piece with half t' tab exposed beyond t' cut line. Avast, me proud beauty! Once that set, I tacked t' other side t' t' overlap tab formin' a butt joint (see photo). Begad! T' result is a perfect-fittin' coupler.

T' egg capsule is a bit larger than most eggs, shiver me timbers, matey, so t' protect t' egg I used two halves o' egg cells from an egg carton, plus a little dog barf padding. I used Mylar tape t' seal t' two capsule halves together, me bucko, though plain old maskin' tape or electrical tape would work fine as well, shiver me timbers, just nay look as nice.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

I wanted t' dress up t' middle o' t' rocket as well as use up more stuff, so selected 6 toothpicks and t' 3 Styrofoam balls. Ya scallywag! I inserted 2 toothpicks into each ball at roughly 90 degree angle, and adjusted t' depth a bit to line up with t' joints where t' BT-50 meets t' pin' pong balls (see photo). I tacked each assembly in pace with CA, mountin' them in alignment with t' 3-fin markings from t' BT-20 (markin' t' BT-50 for 3-fin and alignin' t' marks with t' BT-20 would probably have been smart, shiver me timbers, but that would be out o' character for me).

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

At this point, shiver me timbers, I was ready t' mix up a small batch o' epoxy. Begad! Blimey! I went with 15-minute regular hobby grade (the thick stuff that sort o' oozes out). Blimey! Blimey! Well, blow me down! Blimey! I grabbed some dental floss t' use as a shock cord for t' egg capsule, tied a couple knots in each end, and then taped each end t' an opposin' side o' t' coupler, with t' resultin' loop pushed out what will be t' aft end o' t' coupler (see photo). Arrr! Blimey! I applied a generous bead o' epoxy along t' inside and forward edge of the coupler, me hearties, shiver me timbers, me bucko, then attached it t' t' bottom o' t' egg capsule, trappin' t' floss in betwixt with t' knots outside. Ahoy! Blimey! Begad! Blimey! I set that assembly aside t' cure out.

I then hit each o' t' toothpick/BT-50 joints with a drop o' epoxy t' reinforce them.

I cut out a series o' fins and support pieces, each o' which are shown in t' pattern photos. Avast, me proud beauty! T' 4 main fins are mounted flush with t' aft end. Well, me bucko, blow me down! Each o' these has a 43mm long piece o' BT-20 attached, me hearties, with t' end o' t' BT-20 flush with t' forward edge o' t' fin tip. If aligned correctly, ya bilge rat, these should extend just far enough behind t' fin t' be flush with t' motor tube when stood on end. Begad! T' fill me quota o' 10 toothpicks for t' surprise parts bonus, shiver me timbers, me hearties, I attached one toothpick t' each o' t' 4 pods, servin' as little guns t' defend against hostiles en route.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

I still had a couple more bonus items t' use up, ya bilge rat, so attached a pill bottle t' a 3/32 balsa brace and tacked this onto t' BT-50, with t' open end o' t' capsule facin' rearward. Ya scallywag! My capsule be 2.5" long, matey, just barely big enough to house a Pico altimeter, so I drilled a tiny hole so that it could serve as a workin' payload bay.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

I had t' work in a stick pen somehow, so decided t' up t' armaments a bit and rig a harpoon, me bucko, perfect for hooking on t' a passin' comet or takin' care o' any cosmic whales encountered along t' way. I mounted t' pen usin' another 3/32 support. Begad! Note that this could also serve as a workin' payload, simply by removin' t' aft plug, insertin' a Micromaxx motor, and loosenin' t' pen cartridge slightly. Blimey! Begad! Just be careful mountin' this, as you don't want t' deploy the harpoon into t' back o' one o' t' Styrofoam balls. Aye aye! Aye aye! I aligned mine flush with t' aft end o' t' BT-20.

Normally, I wind up forgettin' about basic stuff like launch lugs and recovery until I get t' t' field, but for a change o' pace decided t' take care o' that before painting. Aye aye! I attached a couple o' 3/16 lugs t' t' BT-60, me bucko, just clearin' t' pin' pong balls. Ya scallywag! Begad! Blimey! As I be gettin' ready t' head t' t' field, I recognized I had still goofed—the lugs would nay clear t' egg capsule. Avast, me proud beauty! Blimey! Easy enough t' correct—I sliced them off, cut a couple o' standoffs (1/2" x 1.5") from 3/32 balsa, matey, arrr, and tacked them back on.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

For t' recovery, I only had 12" chutes t' work with, shiver me timbers, so attached one t' t' dental floss for t' egg capsule, ya bilge rat, and t' other t' t' main BT-20 usin' Keelhaul®©™ and elastic anchored t' a 50/20 centerin' rin' inserted about 6" down from t' forward end o' t' tube.

Finishing:
Before painting, I masked off t' foam balls (most paints will attack and eat t' foam), me hearties, t' pill bottle and the pen/harpoon. Ahoy! I then hit t' whole thin' up with two coats o' white primer, followed by two coats o' yellow. Begad! I then masked off for t' accent orange areas, arrr, and hand painted t' details.

While decals are nay allowed for t' contest, I did find a cool piece o' clip art I eventually will add t' the décor, me hearties, which is included in t' attachment upload for this write-up.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

Flight:
For t' flight, matey, matey, me hearties, I was down t' about t' last day before t' deadline, me hearties, so had t' take whatever weather I could get. Well, blow me down! Avast! I caught a gorgeous day and headed out t' t' field, ya bilge rat, though by t' time I got thar t' winds were pretty stiff—steady at 10 gustin' t' 15. Ya scallywag! Egg lofters tend t' be overly stable, matey, and strong winds typically means bad news. Ya scallywag! Blimey! Still, me hearties, bein' t' steely-eyed missile man that I am, I loaded up a C6-3 and hoped for t' best.

T' flight, as expected, started t' turn into t' wind almost as soon as it left t' rod, me bucko, but despite all the do-dads this is really pretty light and nay too draggy, so t' C6 did a fair job o' pushin' it. Avast! I suspect if I'd gone off a piston, matey, it might even have held a nearly vertical path. As it was, shiver me timbers, it did eventually lean into a horizontal path, so even t' 3 second delay was well past apogee. Avast, me proud beauty! Both chutes deployed at around 100 feet, me bucko, and t' rocket drifted back to within 20 yards o' t' pad after havin' crossed t' soccer field durin' boost. T' egg survived nicely, but one of the toothpicks holdin' a foam ball broke loose on impact, leavin' me with a pretty simple repair.

I did wind up loadin' t' Pico altimeter for t' flight, which reported an apogee o' 228 feet. Ya scallywag! On a calmer day, this would clearly have made it t' 300+, which is actually pretty respectable for a cackle fruit lofter made o' leftover junk. Blimey!

While t' 228 feet is nay likely enough distance t' support colonization o' a distant plant, with minor improvements in propulsion technology, maybe a little antimatter drive, t' Cosmic Chicken would appear t' be fully capable o' transportin' life forms across galaxies.

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