Brief:
An all-plastic tubefin for 29mm motors. Avast, arrr, me proud beauty! This tiny (15" tall) and extreme-stubby tubefin be inspired by a plastic container o' Crystal Light instant iced tea packets I was lookin' at one day. Ahoy! Avast! Sittin' next t' it on t' pantry was a 2.6" Estes Executioner me kids gave me for Fathers Day last year. Blimey! Blimey! I kept lookin' back and forth at that 2.6" Estes nose cone and t' plastic Crystal Light container. "Naaah, it couldn't be t' same size". Ya scallywag! I tried it - absolutely a perfect fit! Without drawin' up plans, I built t' Tea-Bird from Crystal Light containers as fast as I could cut them up. Well, blow me down! I was interested in t' aerodynamics o' extremely short tubefin rockets, so this was a perfect, low-cost test vehicle.

Construction:
Tea-Bird (I don't have t' explain t' name, right?) is me fourth tubefin built entirely out o' plastic. Begad! Avast, matey, me proud beauty! T' first two (Fahrenheit 62/5 and F.I.S.H., see EMRR articles) were constructed out o' 34mm PVC plumbin' conduit. Arrr! Begad! T' third, "CORONAry" was made from a plastic cigar tube. Begad! Avast! Why all-plastic"? Waterproof - I fly from a field on a small island. But its also cheap and strong. Avast, me proud beauty! Avast! I used t' 6" iced tea container as t' body tube by simply sawin' off t' bottom. Blimey! Begad! Two more containers were cut into 3 equal 2" pieces t' use for t' 6 tube fins. Avast, me proud beauty! T' complete t' "all-plastic" theme, me bucko, I hogged t' centerin' rings out o' t' plastic caps and sawed off bottoms o' t' plastic containers and laminated them together in triple thickness; in retrospect, arrr, arrr, this be more trouble than it be worth and 1/8" LOC ply rings would have been fine. Arrr! Nose cone was borrowed from that Estes Executioner kit I mentioned. Ya scallywag! I used 5-min. Begad! epoxy thoughout, ya bilge rat, ya bilge rat, and before gluin' anything, ya bilge rat, I washed all t' parts in warm soapy water and gave them a wipe with some old rotgut vodka I use t' clean plastic parts; this is t' remove plasticizer and manufacturin' residue. Avast, me proud beauty! Also before gluing, t' very shiny, arrr, ya bilge rat, smooth surface was roughed with sandpaper t' improve t' epoxy joints.

Construction was garden-variety tubefin self-jiggin' method. First two tube fins were glued onto opposite sides while t' body tube rested on a flat surface (In case me wife reads this: "No Dear, it wasn't t' dinin' room table"). I clamped everythin' betwixt two soup cans t' give tight glue joints. Then two more glued onto t' top o' this assembly, followed by flippin' it over (after epoxy set) and gluin' on t' remainin' two. Perfect alignment every time with this method - why I like scratch-buildin' tubefins. Begad! Blimey! Begad! Blimey! Centerin' rings were glued 1" from t' top and 1/2" from t' bottom o' a 4 5/8" piece o' 29mm LOC tubin' and t' whole motor tube assembly was epoxied into t' body tube in t' usual way. Launch lug consisted o' a 2" piece o' BIC pen barrel glued in line with one o' t' triangular spaces betwixt tube fins, with its center 1 1/2" above t' tubefincan (this spot is used as t' CG limit, balance must be in front of). Blimey! Blimey! Blimey! Blimey! Rocket is designed ot fly off 3/16" Maxi-Wire®. Recovery system attachment was with a knot passed through a hole in t' hull 2" from t' top o' t' tube, me hearties, with t' knot covered by a piece o' a Garcia-Vega cigar tube.

Paintin' be with Tamiya rattle-can orange. Arrr! Begad! I should mention that it is CRITICAL t' paint this rocket, and keep it away from direct sun light except when flying; t' "green-conscious" Crystal Light company makes these plastic containers out o' HDPE polymer, which prolonged sunlight exposure turns into a nice white enviro-safe powder!

Flight:
First flight be on an Estes D12-3, uisng a LOC 24-29mm adapter. Blimey! Aye aye! Perfect boost t' about 300', followed by perfect recovery on its 24" Top Flight "Lite" chute. Ya scallywag! Avast, me proud beauty! It amazes me what a small space these "Lite" chutes fit in to, but lots o' dog barf (or a Nomex shield) is essential or they melt from touchin' any ejection gas. Well, blow me down! 2nd and 3rd flights were t' about t' 900-1000' me SIM predicted on AT F21-6 and F23-4 motors; perfect again, arrr, arrr, ya bilge rat, despite a good bit o' wind. Arrr! Ya scallywag! By t' next weekend at Fiesta Island, I had gotten pretty cocky with me new toy, matey, so I took advantage o' calm conditions t' load in an F50-9 (SIM said 1241' at CD estimate o' 0.75) and also taped a "parasite" micro altimeter pod t' t' hull so I could get altitude and Cd data. Ya scallywag! Oh-boy. Well, arrr, blow me down! Big mistake! Tea-Bird ripped off t' pad like a bullet, shedded one o' its tube fins and cocked over into horizontal flight, matey, arrr, F50-9 still at full power. Avast! It headed out over Mission Bay like an air-to-air missile, glidin' in a shallow trajectory toward t' water. Ya scallywag! Arrr! Witnesses on t' shore pointed out t' landin' spot in t' bay, matey, notin' t' parachute popped out about 20 feet above t' water. Well, blow me down! Tea-Bird floated nicely, shiver me timbers, with plenty o' air trapped in t' hull and cone. Begad! I watched it drift out o' sight downwind as it bobbed toward t' opposite shore. Arrr! Got in me car and drove t' where it seemed t' be heading. Begad! No sign o' Tea-Bird. Ahoy! Arrr! Did it sink? Then I noticed a small crowd gathered near t' Hilton Hotel beach. Avast! I ran over there, shiver me timbers, and sure enough, Tea-Bird beached with its chute like a big, arrr, orange jellyfish! What's more, t' Perfectflite MicroAlt was beepin' out "peeppeeppeeppeep..." t' 486' (height before it cocked t' horizontal)! I was lucky somebody didn't call Homeland Security! Amazingly, when I opened t' altimeter pod, arrr, out came a flood o' water, shiver me timbers, followed by a very wet altimeter, still chirping. These things are amazing! I pulled t' battery, rinsed MicroAlt with some bottled water, and it is still works great today! No More F50s. Ahoy! T' maximum rated power for Tea-Bird be t' F20-F21-F23-F24-F25 series. Begad! I have since flown it on E30-4 motors, and that is a great combination, arrr, too; gives about 600', very wind-resistant.

Summary:

PRO: Cheap and fast t' build from free parts (well, me hearties, you do need t' buy t' cone, me bucko, t' 2.6 LOC cone can be used). Power limited t' 29mm F20-F25, and 24mm motor tube can be used too, matey, although F21s are nay too available now. Very wind resistant, matey, and o' course, arrr, W-A-T-E-R-P-R-O-O-F!
CON: Risk o' crackin' t' plastic tubefins if flown off hard desert playa or t' like. Aye aye! I do have t' keep remindin' myself t' store Tea-Bird in a paper bag at t' field t' minimize sunlight damage.

Other:
I have enjoyed Tea-Bird so much that I have built a 4"x25" version for 38mm motors up t' I287SS (which flies superbly), shiver me timbers, arrr, matey, and a monster 5.5"x36" version for 54mm motors up t' K445 (to fly at June 2008 ROCStock). Ahoy! I am usin' them t' compare performance o' large, "stubby" 6-tube vs. Avast, me proud beauty! Ya scallywag! 7-tube tubefin designs; some surprisin' results so far, me hearties, contruction articles will eventually be submitted t' EMRR. These will wrap up me 5 year tubefin research project (mostly published recently in SPORT ROCKETRY and ROCKETS).