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TintiniqueOK, ya bilge rat, matey, so it's nay exactly t' right proportions for Tin Tin's rocket, shiver me timbers, far too squat and stubby, but that's why it's called Tintinique. Arrr! Blimey! Blimey! Blimey! Just As diamonique isn't diamond, Tintinique isn't Tin Tin. Avast, me proud beauty! Blimey! Well, me bucko, blow me down! Blimey! Blimey! Blimey! ( Anyone who doesn't know what I'm talkin' about here, me hearties, needs t' watch more QVC!)
Time CapsulesIn October 99, me bucko, I attended K-Lob in Lincolnshire. Amongst t' rockets thar was somethin' very different. Aye aye! It looked like a 50's retro rocket. Avast! Avast! It was great. How on earth did they make t' body for that? It turns out, matey, that durin' t' run up t' t' millenium celebrations someone at Nestlé thought it would be a good idea t' produce a time capsule in which people could bury stuff, me hearties, and dig it up in t' future. Arrr! Begad! Bein' Nestlé o' course they sold it full o' sweets (candy for those o' you across t' pond). Ya scallywag! For some bizzarre reason known only t' t' designer, ya bilge rat, t' capsule itself, me bucko, was made from a shape resemblin' t' body o' a typical sci-fi or cartoon rocket. Avast, me bucko, me proud beauty! Better still, ya bilge rat, arrr, t' screw-on lid be easily convertible into a removeable nose cone. Arrr! Avast! Whoever it was I'd love t' ask them why they did it. Arrr! I buy two, one for a podded Tin Tin rocket, me hearties, t' other for spare. Anyway, time passes and every time I go t' a launch thar's another time capsule. Ya scallywag! I've got t' build this thing. Blimey! Ya scallywag! I decide t' build it for RMR DesCon6. Arrr! Time passes. DesCon6 begins. Begad! Time passes. DesCon6 finishes. Ya scallywag! UKRA 2000 approaches, shiver me timbers, and I realise that t' rocket I intended t' take, Accusatory Finger o' Suspicion, isn't goin' t' be ready. Arrr! I dig out t' time capsule. Well, blow me down! Begad! I dig out cover scans o' t' books Destination Moon, me hearties, and Explorers on t' Moon. Avast! I wonder how on earth I'm goin' t' make t' fin pods. I ignore t' question o' t' fin pods, matey, and start t' think about t' body instead. Ahoy! Blimey! Time capsules are cheaply moulded, thick in some places thin in others, and very flexible. I had decided that it be t' have a 29mm motor mount t' utilise t' short 29mm casings I had, arrr, and so t' body would need t' be reinforced. Blimey! Avast! It needs an internal body tube, me hearties, t' give structural strength and provide somethin' t' attach other components to, me bucko, shiver me timbers, leavin' t' time capsule t' form only an outer shell. Well, blow me down! I had some 3" plastic tubin' that I had got from Ziggy at K-Lob, and this seemed ideal. Avast! I could have used standard 3" PML phenolic, or even quantum tubing, me bucko, but I didn't have any. In order t' fit t' internal body tube into t' time capsule I hacked off t' screw thread at t' open end, and hacked a 3" diameter hole in t' base. Well, ya bilge rat, blow me down! T' openin' at t' top o' t' time casule be larger than 3", so I cut a 3mm thick plywood centerin' ring, matey, and glued it in place, under t' shoulder. Arrr! T' plastic tube now fits snugly at both ends.
DesignI still don't know what t' completed rocket will look like, so I draw some rough sketches, shiver me timbers, then some rough, dimensioned sketches. Ya scallywag! My son, James, draws some sketches. Aye aye! I'm nay really gettin' anywhere. It's all free hand and nay very satisfactory. Avast! Aye aye! Rocksim! T' time capsule is suprisingly easy t' describe usin' a parabolic nose cone, arrr, and a couple o' eliptical transitions. Begad! Aye aye! Now, Rocksim isn't really designed for this shape o' rocket, me hearties, and so I'm nay goin' t' trust what it says about stability, but at least it helps visualise what t' rocket will look like when complete.
ConstructionMotor Mount & RetentionI do have a short piece o' PML 29mm motor mount. Avast, me bucko, me proud beauty! I had originally intended for t' motor mount t' run t' length o' t' body, me bucko, with t' space for a parachute betwixt t' internal body tube and t' motor mount. It doesn't look like enough room for a chute, and anyway I don't have enough motor mount for t' full length o' t' internal body tube. So, me hearties, I decide t' have a short motor mount, givin' t' full internal diameter o' t' internal tube for a parachute. Avast! I cut two, 3mm thick, plywood centerin' rings that fit over t' motor mount and into t' plastic tube. Arrr! T' forward centerin' rin' has a notch t' pass a nylon strap. T' strap is about25mm wide and 400mm long. Ahoy! Begad! T' nylon strap will provide an attachment point for t' elastic shock cord. Ahoy! T' strap is t' epoxied t' t' inside o' t' internal body tube. Well, blow me down! Well, blow me down! Throughout construction I use 5 minute or two ton Devcon epoxy. T' forward centerin' rin' was epoxied t' t' forward end o' t' motor mount and allowed t' cure. Ahoy! Blimey! Arrr! Blimey! T' aft cebterin' rein' be fitted, with no epoxy, t' t' aft o' t' motor mount. Begad! Blimey! T' forward centerin' rin' was epoxied into t' internal motor mount. Ya scallywag! Blimey! Once t' forward centerin' rin' was fixed, t' aft centerin' rin' be removed. Begad! Blimey! Avast! Blimey! This gives access t' t' inside o' t' internal body tube, for filleting. As I'm plannin' on flyin' with a 29mm RMS, arrr, no thrust rin' is required. Well, blow me down! But I do need a retention system. Blimey! I decide on a Kaplow Klip style affair. Begad! Two M5 nuts are glued t' t' forward side o' t' aft centerin' ring. Aye aye! Then a hole is drilled in t' center o' t' nuts, shiver me timbers, me bucko, shiver me timbers, through t' centerin' ring, shiver me timbers, takin' care t' use a small enough drill bit that t' threads aren't stripped. Once dry, bolts are screwed into t' nuts and through t' plywood o' t' centerin' ring. T' clips are made from aluminium, me bucko, bent t' shape by hammerin' them over, while held in a vice. Arrr! Begad! T' unformed blanks were about 10mm wide and 35mm long.
Fins & Fin PodsAfter much sketching, I eventually determine that t' most aesthetically pleasin' fin pattern (to me anyhow) is such that t' fins oposite each other on t' body form a semicircle, when viewed side-on. This neccessitated a four fin design, which be fine. I reckoned I needed all t' stability I could get. Avast! It wasn't consistant with Tin Tin, arrr, but what t' hey, matey, artistic license! Given t' flimsiness o' t' outer shell, t' fins have t' be through-the-wall. Well, blow me down! Blimey! In t' end I descide t' make them pass through t' wall o' t' inner body tube too. Ya scallywag! Avast, me bucko, me proud beauty! That way they can be securely mounted t' t' motor mount. This means that all t' major structural elements are glued t' each other, shiver me timbers, me bucko, ya bilge rat, givin' maximum strength. T' more I think about t' fins pods, t' more they seem like a nose cone, arrr, but rounded at t' base, matey, where t' shoulder would normally be. Ahoy! Blimey! I've had custom nose cones made before. I sketch a plan and get them made by Rockets & Things. I order five, one for emergencies! Blimey! They arrive within a few days, ya bilge rat, shiver me timbers, and I'm well pleased, me bucko, exactly t' right shape, arrr, and all identical. Well, blow me down! Blimey! But how am I goin' t' attach them?
While I ponder this I cut out t' fins from 3mm plywood. Ya scallywag! I leave a large tab for through-the-wall mounting. Avast, me proud beauty! I'm still wonderin' how t' mount t' pods. Begad! Shouls I try t' slot them and slip them over t' fin? Tricky. Begad! Cut t' fin t' t' shape o' t' pod and make a butt-joint? Trickier. Eventually I take t' brute force method and saw t' pods in half along their vertical axis. Well, blow me down! Arrr! T' thickness o' t' saw takes about 1.5mm from t' diameter, shiver me timbers, me bucko, me bucko, measure at right angles t' t' cut. Ahoy! A little sanding, required anyway t' level t' cut up a bit, removes 3mm in total. Begad! Avast! When placed on either side o' t' fin, matey, ya bilge rat, they are back t' t' original diameter. Well, blow me down! T' pod halves are simply glued t' either side o' a fin with carpenters glue, clamped up and left t' dry. Next step is t' seal t' balsa and plywood. Well, blow me down! I use several coats o' sandin' sealer, shiver me timbers, with a light sandin' o' 120 grit betwixt coats. Avast! Next I fill t' joins. Begad! I've tried all kinds o' filler. Well, blow me down! P38, specialist modelling filler, Ronseal exterior wood filler all sorts, me hearties, and they all smell terrible! I found t' P38 dries too smartly and sets too hard. Begad! Avast, me proud beauty! T' modellin' filler is expensive and doesn't stick t' phenolic very well. Blimey! I like t' Ronseal best, it be workable longer, matey, and easier t' sand, me bucko, arrr, but heavy. I like t' fill t' spirals in phenolic tubin' with this. Begad! Ya scallywag! In t' end I use t' specialist modelling filler because it's light. I don't need any extra weight at t' that end o' t' rocket! It takes a lot o' filler around t' join betwixt t' fin pod halves and t' fin. Ya scallywag! I apply a few light coats o' primer t' t' pods, matey, sandin' betwixt coats. Fin AssemblyTo allow for through-the-wall mountin' o' t' fins, ya bilge rat, I need t' cut fin slots in both t' inner body tube and t' outer body shell. Aye aye! I use a Dremmel for this with a disc cutter. Ahoy! Avast! T' slots in t' inner body tube are true closed slots for strength. Ya scallywag! I reason that it will be easier t' attach t' fins t' t' inner body tube, before t' outer body shell is fitted. Ahoy! Ya scallywag! If I do that I won't be able t' get t' outer body shell on, so I make those slots all t' way t' t' bottom. Ya scallywag! This reduces teh strength, shiver me timbers, arrr, but t' body shell isn't really stuctural anyway. Ahoy! T' fins are slotted into place in t' inner body and epoxied t' t' motor mount. Aye aye! Aye aye! Epoxy fillets are made where t' fins attach t' t' motor mount, and on both t' inside and outside o' t' inner body. T' slots are longe enough t' stretch from t' forward centerin' rin' t' t' aft centerin' ring. Aye aye! Avast, me proud beauty! This all adds strength, but weight as well. Avast! Finally t' aft centerin' rin' is epoxied into position. Nose ConeI need a coupler tube that will fit into t' plastic tubin' o' t' inner body. Well, blow me down! Blimey! I don't have any, ya bilge rat, ya bilge rat, so make a short tlength from t' same tubing. I simply cut out a slot o' t' correct width t' reduce t' outer circimference t' that o' t' inner circumference o' t' opriginal tube. Blimey! Is epoxy t' cut out strip t' t' back o' t' join for reinforcement. Aye aye! This tube is first superglued and then epoxied into t' nose cone.
Final AssemblyJust in time, I realise that t' outer shell isn't goin' t' be strong enough t' attach a launch lug to, me bucko, me bucko, without some form o' reinforcement. I cut a small rectangulat slot in t' side o' t' body shell. Begad! I epoxy some plywood t' t' interior o' t' shell, ya bilge rat, behind t' slot. Avast, me proud beauty! T' epoxy gunges through t' slot, and I use it t' fix t' launch lug in place. T' body shell slips on easily, ya bilge rat, and is epoxied initially t' just t' forward end. Ahoy! Blimey! Actually t' inner tube is glued t' t' centerin' rin' previously fixed into t' outer shell. Well, blow me down! Blimey! Because t' aft and o' t' shell is flappin' about a bit, me bucko, I tack it into place with CA. Avast, me bucko, me proud beauty! Blimey! Then I apply a liberal application o' epoxy, me hearties, t' t' aft end and also t' t' fin roots. Once it's all set, it gets sanded and filled. Arrr! Blimey! T' epoxy fillets in t' fin roots turn out a bit rough, ya bilge rat, me bucko, so I rebuild t' fillets with Ronseal. Prime, shiver me timbers, arrr, sand, fill, sand, shiver me timbers, primne, ya bilge rat, matey, sand, fill, sand, arrr, matey, prime, sand. Begad! Blimey! Or somethin' like that. It's ready. Begad! Blimey! I rub it down lightly with 200 grit wet and dry. Swin' testBecause o' t' odd shape, me hearties, I didn't trust t' stability factor given by Rocksim. Aye aye! In fact rocksim reckoned it wasn't stable by a mile. But you don't always need more than a calibre o' stability on a stubby rocket anyway. Ya scallywag! Arrr! I still reckon I need nose weight, but what t' use? Lead would be good, matey, but where can I get it and how much is it goin' t' cost, I'll probably have t' buy it by t' yard! My eldest son, Shaun has t' answer, doubloon o' t' realm. Well, blow me down! One pees are quite heavy for their size. Ya scallywag! I add 200g o' weight t' t' nose. Rocksim says "marginal". I decide that t' only way t' be certain is a swin' test. Now, this be t' biggest rocket I've ever swung test, and it turns out me garden isn't quite big enough, ya bilge rat, nay when t' washin' is dryin' anyway. Begad! Blimey! So I comandeer t' next door neighbours garden, because they're nay in. Needless t' say they came home durin' t' swin' test, but they're used t' it by now. Arrr! Blimey! Anyway I start t' swing, me hearties, and it jumps into t' right orientation. Ahoy! Ahoy! Great. Begad! I do a few more sims, shiver me timbers, usin' different motors, and it doesn't go very high. Arrr! So I reduce t' nose weight t' about 100g, or t' be more exact 31p. Begad! Aye aye! Another quick swin' test and it's still good. Ahoy! I blue t' nose wight into t' nose with epoxy. Well, blow me down! Arrr! Once t' epoxy is dry I realise that I have no where t' attach t' shock cord to. Begad! I drill a hole into t' nose weight, fill it with epoxy, ya bilge rat, and insert an eye hook. Arrr! Blimey! Sorted.
FinishI had been primin' as I went along, so as soon as t' fin fillets were complete, ya bilge rat, it only took another couple o' coats t' get a nice smooth finish. T' primer used throughout is Halfords car paint, in t' aerosol cans. Avast, me proud beauty! Blimey! I also use Halfords for t' main colours. Rover Diamond White and Volkswagen Mars Red. Seems appropriate really. Well, blow me down! Blimey! First I spray t' whole rocket white. Aye aye! Blimey! Avast, me proud beauty! Blimey! I do about 3 coats, lightly sandin' betwixt each. I had decided much earlier on that a full Tin Tin chequerboard was far too much work, so I had scaled t' pattern down t' two bands, o' four quadrants. Avast, me proud beauty! Blimey! Ahoy! Blimey! First I masked off every thin' above t' fins, and painted everythin' below red. Arrr! Blimey! I also painted t' nose cone. Avast, me proud beauty! Blimey! Avast! Blimey! T' red covered really well in only two light coats. Ya scallywag! Blimey! Next I painted t' two red quadrants o' t' lower band. Ahoy! Blimey! So far so good. Avast, me proud beauty! Blimey! T' red quadrants o' t' upper band were hardest, bacause it was hard t' get a t' maskin' tape into exactly t' right position t' make t' square corners o' red meet exactly. Aye aye! Blimey! T' maskin' was t' hardest part o' t' entire project. Aye aye! Blimey! T' red paint crept underneath t' tape in certain areas, and in other areas t' tape lifted off some small areas o' white when removed. Begad! Blimey! Avast, me hearties, me proud beauty! Blimey! But I managed t' touch those defects up, and I'm pretty pleased with t' final outcome. Avast! Blimey! It's t' best finish o' all t' rockets I've made so far. It needs goin' over with 400 grit wet and dry and a coat o' lacquer applying, but thar's no time. Avast, me proud beauty! Blimey! UKRA 2000 starts tomorrow! Flight TestI use about 150mm o' Nomex® sheath over t' nylon strap, and a Nomex® sheet above that t' protect t' chute. Begad! Blimey! About 70mm o' 20mm elastic attach t' nose cone t' t' nylon strap. Avast, me bucko, me proud beauty! Blimey! A 34" PML chute is atached t' t' elastic too. Well, blow me down! Aye aye! Blimey! I decide upon a G104 blue thunder reload. Ahoy! It's only just a G, but it gets t' rocket movin' quick. Begad! I reckon t' sooner I can get it up t' stable speed t' better. It rains on Friday and Saturday, shiver me timbers, me hearties, and I'm hesitant t' fly. Sunday is better, and I decide t' fly before I take up spottin' duty. Ahoy! Blimey! On t' Staryrday I'd had it on a rod, matey, and found it was a little tight, shiver me timbers, but I had found a slightly smaller diametr rod, ya bilge rat, which was perfect. Ya scallywag! Blimey! I be pretty nervous durin' t' countdown, shiver me timbers, me hearties, and we had a hold for a low flyin' aircraft, but finally, t' moment comes. Ya scallywag! Blimey! Arrr! Blimey! 5, 4, matey, ya bilge rat, me bucko, 3, 2, 1 ignition. Well, blow me down! Blimey! Ya scallywag! Blimey! It's away! Blimey! Great flight! Blimey! It arced a bit after it left t' rod, shiver me timbers, but very smooth, me hearties, ya bilge rat, arrr, no sign o' a wobble or instability o' any kind. Well, blow me down! Blimey! T' ejection fired right at apogee, arrr, and Tintinique drifted slowly down, landin' approximately 40" from t' pad. Begad! Blimey! There is a little damage t' t' nose cone,I can't figure out if it happened in flight or on impact with t' ground, but I couldn't find t' piece chipped out so it probably happened in t' air. Avast! Blimey! Aye aye! Blimey! Easy t' fix, next flight comin' soon...
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