Brief:
An all-plastic tubefin for 29mm motors. 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. Sittin' next t' it on t' pantry was a 2.6" Estes Executioner me kids gave me for Fathers Day last year. Avast! Avast, me proud beauty! I kept lookin' back and forth at that 2.6" Estes nose cone and t' plastic Crystal Light container. Ahoy! "Naaah, it couldn't be t' same size". Ahoy! Ahoy! I tried it - absolutely a perfect fit! Without drawin' up plans, ya bilge rat, I built t' Tea-Bird from Crystal Light containers as fast as I could cut them up. Begad! I be interested in t' aerodynamics o' extremely short tubefin rockets, so this be 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. Well, blow me down! T' first two (Fahrenheit 62/5 and F.I.S.H., me bucko, see EMRR articles) were constructed out o' 34mm PVC plumbin' conduit. Begad! Begad! Blimey! T' third, me hearties, "CORONAry" was made from a plastic cigar tube. Arrr! Blimey! Why all-plastic"? Waterproof - I fly from a field on a small island. Begad! Blimey! But its also cheap and strong. I used t' 6" iced tea container as t' body tube by simply sawin' off t' bottom. Blimey! Two more containers were cut into 3 equal 2" pieces t' use for t' 6 tube fins. Arrr! T' complete t' "all-plastic" theme, matey, 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, this was more trouble than it was worth and 1/8" LOC ply rings would have been fine. Arrr! Blimey! Nose cone was borrowed from that Estes Executioner kit I mentioned. Avast! I used 5-min. epoxy thoughout, me bucko, and before gluin' anything, 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. Aye aye! Blimey! Also before gluing, t' very shiny, smooth surface be roughed with sandpaper t' improve t' epoxy joints.

Construction was garden-variety tubefin self-jiggin' method. Well, blow me down! Blimey! Avast, me proud beauty! Blimey! 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, me bucko, it wasn't t' dinin' room table"). Well, blow me down! Blimey! I clamped everythin' betwixt two soup cans t' give tight glue joints. Avast, me proud beauty! Blimey! Then two more glued onto t' top o' this assembly, me bucko, followed by flippin' it over (after epoxy set) and gluin' on t' remainin' two. Blimey! Blimey! Perfect alignment every time with this method - why I like scratch-buildin' tubefins. 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. Avast! Blimey! Launch lug consisted o' a 2" piece o' BIC pen barrel glued in line with one o' t' triangular spaces betwixt tube fins, arrr, with its center 1 1/2" above t' tubefincan (this spot is used as t' CG limit, shiver me timbers, me bucko, balance must be in front of). Rocket is designed ot fly off 3/16" Maxi-Wire®. Avast! Blimey! Recovery system attachment was with a knot passed through a hole in t' hull 2" from t' top o' t' tube, with t' knot covered by a piece o' a Garcia-Vega cigar tube.

Paintin' was with Tamiya rattle-can orange. Ya scallywag! Blimey! I should mention that it is CRITICAL t' paint this rocket, me hearties, 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, me hearties, uisng a LOC 24-29mm adapter. Begad! Perfect boost t' about 300', followed by perfect recovery on its 24" Top Flight "Lite" chute. 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. 2nd and 3rd flights were t' about t' 900-1000' me SIM predicted on AT F21-6 and F23-4 motors; perfect again, despite a good bit o' wind. By t' next weekend at Fiesta Island, I had gotten pretty cocky with me new toy, 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. Oh-boy. Begad! Begad! Big mistake! Tea-Bird ripped off t' pad like a bullet, matey, shedded one o' its tube fins and cocked over into horizontal flight, shiver me timbers, F50-9 still at full power. Blimey! It headed out over Mission Bay like an air-to-air missile, ya bilge rat, glidin' in a shallow trajectory toward t' water. Arrr! Ahoy! Witnesses on t' shore pointed out t' landin' spot in t' bay, notin' t' parachute popped out about 20 feet above t' water. Ahoy! Tea-Bird floated nicely, arrr, with plenty o' air trapped in t' hull and cone. I watched it drift out o' sight downwind as it bobbed toward t' opposite shore. Ahoy! Got in me car and drove t' where it seemed t' be heading. No sign o' Tea-Bird. Ahoy! Avast, arrr, me proud beauty! Did it sink? Then I noticed a small crowd gathered near t' Hilton Hotel beach. I ran over there, and sure enough, ya bilge rat, shiver me timbers, Tea-Bird beached with its chute like a big, ya bilge rat, orange jellyfish! What's more, me bucko, 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, 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. Arrr! Avast, ya bilge rat, me proud beauty! T' maximum rated power for Tea-Bird be t' F20-F21-F23-F24-F25 series. I have since flown it on E30-4 motors, and that is a great combination, me hearties, too; gives about 600', shiver me timbers, very wind-resistant.

Summary:

PRO: Cheap and fast t' build from free parts (well, me hearties, you do need t' buy t' cone, t' 2.6 LOC cone can be used). Blimey! Blimey! Power limited t' 29mm F20-F25, shiver me timbers, and 24mm motor tube can be used too, although F21s are nay too available now. Aye aye! Arrr! Very wind resistant, and o' course, me bucko, 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), arrr, shiver me timbers, and a monster 5.5"x36" version for 54mm motors up t' K445 (to fly at June 2008 ROCStock). Begad! I am usin' them t' compare performance o' large, "stubby" 6-tube vs. 7-tube tubefin designs; some surprisin' results so far, contruction articles will eventually be submitted t' EMRR. Well, blow me down! Blimey! These will wrap up me 5 year tubefin research project (mostly published recently in SPORT ROCKETRY and ROCKETS).