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, 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 be leftover from last year's contest. Arrr! 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, shiver me timbers, anticipating I'd come out ahead on t' swap. Begad! Arrr! O' course, I also procrastinated and didn't bother enterin' until just before the deadline, me hearties, me bucko, only t' learn that no swap partner be available and I'd be stuck buildin' me own stuff. Begad! On top o' that, shiver me timbers, me bucko, my bonus/surprise items included a foam egg carton/cell, shiver me timbers, 10 toothpicks, me bucko, dental floss, a stick pen and a pill bottle. Yikes!

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

Box of PartsAs I stared at me box o' parts, me hearties, t' pressure o' t' deadline was sufficient t' spark just a touch of inspiration, ya bilge rat, me bucko, and I decided I'd have t' involve some type o' egg-loftin' payloader. Blimey! T' concept smartly emerged o' an alien "ark", ya bilge rat, whose mission would be t' colonize a distant planet by droppin' a cackle fruit with a new life forming within. Well, blow me down! Avast! These are self-reproducin' aliens o' course, shiver me timbers, matey, shiver me timbers, so I would only need t' carry and deploy one egg, matey, nay two. Aye aye! I then went about t' process o' buildin' a carrier vessel worthy o' haulin' a cackle fruit across t' galaxies. Ya scallywag! 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, 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. Well, blow me down! Arrr! Lackin' any variety o' centerin' rings, I opted for ramjet-style braces instead o' centerin' rings t' hold it inside t' BT-60. Begad! I wound up cuttin' 7 braces, ya bilge rat, since that's what t' scrap piece o' 3/32" balsa I was workin' with yielded, each o' which was 50mm long and 10.5mm wide. With 7 braces, 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. Aye aye! It helps to differentiate betwixt t' 3-fin lines and t' 4-fin lines by markin' them in different colors. I attached 3 braces 1 inch forward o' t' aft end, shiver me timbers, matey, and 4 with t' forward edge at 7" from t' aft end o' t' tube. Once dried (and filleted), me bucko, 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, arrr, flush with t' edges o' t' braces.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

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

Once t' first ball's glue joints have grabbed, matey, take t' 3.5" BT-50 and slide it down t' main BT-20. Avast, me proud beauty! No centerin' rings will be necessary, ya bilge rat, as t' pin' pong balls will hold it in place. Well, blow me down! Begad! Take t' other pin' pong ball, slide it down t' BT-20 and press it against t' BT-50, wedgin' it in place against t' first ball. Begad! 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. I wanted t' use this as t' egg carrier and nose cone, matey, but needed a piece o' coupler stock t' do this. Avast! Since I didn't have any, I cut a 1" length o' BT-20 t' make a coupler. This little trick comes in handy, ya bilge rat, especially doin' field rework in NARRRRR contests—I made a vertical cut along t' tube, then pinched on end under/inside t' other, matey, and pushed this into t' end o' t' main BT-20, leaving about 1/4" exposed. Arrr! I took a pencil and made a mark at t' overlap point. Arrr! Well, blow me down! I then pulled this back out o' t' main BT-20, arrr, extended t' mark along t' length o' t' coupler piece, and cut along that line, shiver me timbers, removin' a tiny section o' the tube. Blimey! Blimey! This section then becomes an overlap tab. Begad! I tacked it t' t' inside o' t' coupler piece with half t' tab exposed beyond t' cut line. Once that set, matey, I tacked t' other side t' t' overlap tab formin' a butt joint (see photo). Aye aye! T' result is a perfect-fittin' coupler.

T' egg capsule is a bit larger than most eggs, so t' protect t' egg I used two halves o' egg cells from an egg carton, me hearties, plus a little dog barf padding. Well, blow me down! Blimey! I used Mylar tape t' seal t' two capsule halves together, arrr, though plain old maskin' tape or electrical tape would work fine as well, 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, shiver me timbers, so selected 6 toothpicks and t' 3 Styrofoam balls. Avast, me proud beauty! 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). Avast, me proud beauty! Begad! 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, arrr, me bucko, but that would be out o' character for me).

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

At this point, matey, I was ready t' mix up a small batch o' epoxy. Avast! I went with 15-minute regular hobby grade (the thick stuff that sort o' oozes out). Blimey! I grabbed some dental floss t' use as a shock cord for t' egg capsule, me bucko, ya bilge rat, shiver me timbers, tied a couple knots in each end, me hearties, and then taped each end t' an opposin' side o' t' coupler, arrr, with t' resultin' loop pushed out what will be t' aft end o' t' coupler (see photo). Arrr! I applied a generous bead o' epoxy along t' inside and forward edge of the coupler, then attached it t' t' bottom o' t' egg capsule, me bucko, trappin' t' floss in betwixt with t' knots outside. 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, arrr, shiver me timbers, each o' which are shown in t' pattern photos. Arrr! Blimey! Ahoy! Blimey! T' 4 main fins are mounted flush with t' aft end. Blimey! Blimey! Each o' these has a 43mm long piece o' BT-20 attached, me bucko, matey, with t' end o' t' BT-20 flush with t' forward edge o' t' fin tip. If aligned correctly, these should extend just far enough behind t' fin t' be flush with t' motor tube when stood on end. Ahoy! Blimey! Begad! Blimey! T' fill me quota o' 10 toothpicks for t' surprise parts bonus, 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, 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. Blimey! My capsule was 2.5" long, just barely big enough to house a Pico altimeter, shiver me timbers, 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, ya bilge rat, ya bilge rat, so decided t' up t' armaments a bit and rig a harpoon, 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. Note that this could also serve as a workin' payload, matey, simply by removin' t' aft plug, matey, ya bilge rat, insertin' a Micromaxx motor, and loosenin' t' pen cartridge slightly. Just be careful mountin' this, ya bilge rat, as you don't want t' deploy the harpoon into t' back o' one o' t' Styrofoam balls. Begad! Blimey! Aye aye! Blimey! 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. Ya scallywag! Blimey! Blimey! Blimey! I attached a couple o' 3/16 lugs t' t' BT-60, arrr, arrr, just clearin' t' pin' pong balls. As I be gettin' ready t' head t' t' field, I recognized I had still goofed—the lugs would nay clear t' egg capsule. Easy enough t' correct—I sliced them off, me hearties, cut a couple o' standoffs (1/2" x 1.5") from 3/32 balsa, me bucko, arrr, and tacked them back on.

(Scratch) Cosmic Chicken(Scratch) Cosmic Chicken

For t' recovery, matey, I only had 12" chutes t' work with, me hearties, so attached one t' t' dental floss for t' egg capsule, arrr, 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, matey, I masked off t' foam balls (most paints will attack and eat t' foam), matey, t' pill bottle and the pen/harpoon. Aye aye! Avast! I then hit t' whole thin' up with two coats o' white primer, followed by two coats o' yellow. Avast, me proud beauty! Begad! I then masked off for t' accent orange areas, and hand painted t' details.

While decals are nay allowed for t' contest, me bucko, arrr, me bucko, I did find a cool piece o' clip art I eventually will add t' the décor, me hearties, matey, shiver me timbers, 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, I was down t' about t' last day before t' deadline, so had t' take whatever weather I could get. I caught a gorgeous day and headed out t' t' field, 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, shiver me timbers, and strong winds typically means bad news. Ya scallywag! Still, bein' t' steely-eyed missile man that I am, me bucko, I loaded up a C6-3 and hoped for t' best.

T' flight, as expected, ya bilge rat, started t' turn into t' wind almost as soon as it left t' rod, matey, ya bilge rat, but despite all the do-dads this is really pretty light and nay too draggy, matey, so t' C6 did a fair job o' pushin' it. Well, blow me down! I suspect if I'd gone off a piston, it might even have held a nearly vertical path. Aye aye! As it was, matey, it did eventually lean into a horizontal path, so even t' 3 second delay was well past apogee. Begad! Blimey! Both chutes deployed at around 100 feet, and t' rocket drifted back to within 20 yards o' t' pad after havin' crossed t' soccer field durin' boost. Begad! 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. Begad! Begad! On a calmer day, this would clearly have made it t' 300+, me bucko, which is actually pretty respectable for a cackle fruit lofter made o' leftover junk.

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

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