Tintinique

Tintinique

OK, so it's nay exactly t' right proportions for Tin Tin's rocket, shiver me timbers, matey, far too squat and stubby, ya bilge rat, but that's why it's called Tintinique. Just As diamonique isn't diamond, Tintinique isn't Tin Tin. Arrr! Blimey! ( Anyone who doesn't know what I'm talkin' about here, needs t' watch more QVC!)

Nestlé time capsule

Centerin' rin' in position

Time Capsules

In October 99, I attended K-Lob in Lincolnshire. Begad! Amongst t' rockets thar was somethin' very different. Blimey! It looked like a 50's retro rocket. It be great. How on earth did they make t' body for that? It turns out, 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, and dig it up in t' future. Aye aye! Blimey! Bein' Nestlé o' course they sold it full o' sweets (candy for those o' you across t' pond). For some bizzarre reason known only t' t' designer, shiver me timbers, t' capsule itself, was made from a shape resemblin' t' body o' a typical sci-fi or cartoon rocket. Begad! Blimey! Blimey! Blimey! Better still, t' screw-on lid be easily convertible into a removeable nose cone. Begad! Blimey! Whoever it was I'd love t' ask them why they did it. I buy two, one for a podded Tin Tin rocket, t' other for spare.

Anyway, me hearties, shiver me timbers, me hearties, time passes and every time I go t' a launch thar's another time capsule. Well, me hearties, blow me down! I've got t' build this thing. Arrr! I decide t' build it for RMR DesCon6. Blimey! Time passes. Aye aye! DesCon6 begins. Time passes. Aye aye! DesCon6 finishes. Avast! Avast! UKRA 2000 approaches, and I realise that t' rocket I intended t' take, Accusatory Finger o' Suspicion, matey, isn't goin' t' be ready. I dig out t' time capsule. I dig out cover scans o' t' books Destination Moon, matey, and Explorers on t' Moon. I wonder how on earth I'm goin' t' make t' fin pods.

I ignore t' question o' t' fin pods, ya bilge rat, and start t' think about t' body instead. Time capsules are cheaply moulded, thick in some places thin in others, shiver me timbers, me bucko, and very flexible. I had decided that it be t' have a 29mm motor mount t' utilise t' short 29mm casings I had, me hearties, shiver me timbers, and so t' body would need t' be reinforced. Begad! It needs an internal body tube, t' give structural strength and provide somethin' t' attach other components to, leavin' t' time capsule t' form only an outer shell. Ahoy! I had some 3" plastic tubin' that I had got from Ziggy at K-Lob, and this seemed ideal. Arrr! Ahoy! I could have used standard 3" PML phenolic, matey, ya bilge rat, ya bilge rat, or even quantum tubing, 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, me bucko, me bucko, and hacked a 3" diameter hole in t' base. Blimey! Aye aye! T' openin' at t' top o' t' time casule be larger than 3", me bucko, matey, so I cut a 3mm thick plywood centerin' ring, me hearties, and glued it in place, under t' shoulder. Avast, me proud beauty! Well, shiver me timbers, blow me down! T' plastic tube now fits snugly at both ends.

T' preliminary sketches

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Design

I still don't know what t' completed rocket will look like, ya bilge rat, so I draw some rough sketches, then some rough, dimensioned sketches. Avast, me proud beauty! Blimey! My son, me bucko, shiver me timbers, James, draws some sketches. I'm nay really gettin' anywhere. Arrr! It's all free hand and nay very satisfactory. Well, blow me down! Rocksim! T' time capsule is suprisingly easy t' describe usin' a parabolic nose cone, ya bilge rat, and a couple o' eliptical transitions. Ahoy! 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.

Inner body tube, motor mount

Inner body tube, me hearties, me hearties, parachute bay

Aft centerin' ring, retainin' nuts

Aft centerin' ring, shiver me timbers, shiver me timbers, retainin' clips

Construction

Motor Mount & Retention

I do have a short piece o' PML 29mm motor mount. Aye aye! Blimey! I had originally intended for t' motor mount t' run t' length o' t' body, me hearties, ya bilge rat, with t' space for a parachute betwixt t' internal body tube and t' motor mount. Blimey! Avast, me proud beauty! Blimey! It doesn't look like enough room for a chute, me hearties, and anyway I don't have enough motor mount for t' full length o' t' internal body tube. So, ya bilge rat, me bucko, ya bilge rat, I decide t' have a short motor mount, ya bilge rat, givin' t' full internal diameter o' t' internal tube for a parachute. Aye aye! I cut two, ya bilge rat, matey, 3mm thick, ya bilge rat, me hearties, plywood centerin' rings that fit over t' motor mount and into t' plastic tube. Avast! Blimey! T' forward centerin' rin' has a notch t' pass a nylon strap. Ahoy! Aye aye! Blimey! T' strap is about25mm wide and 400mm long. Avast! Blimey! T' nylon strap will provide an attachment point for t' elastic shock cord. Begad! Begad! Blimey! T' strap is t' epoxied t' t' inside o' t' internal body tube. Arrr! Aye aye! Blimey! 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. Arrr! Blimey! T' aft cebterin' rein' be fitted, with no epoxy, t' t' aft o' t' motor mount. T' forward centerin' rin' was epoxied into t' internal motor mount. Aye aye! Blimey! Once t' forward centerin' rin' be fixed, t' aft centerin' rin' was removed. Aye aye! Blimey! Aye aye! Blimey! This gives access t' t' inside o' t' internal body tube, for filleting.

As I'm plannin' on flyin' with a 29mm RMS, shiver me timbers, ya bilge rat, no thrust rin' is required. But I do need a retention system. Begad! Ya scallywag! Blimey! I decide on a Kaplow Klip style affair. Well, blow me down! Blimey! Two M5 nuts are glued t' t' forward side o' t' aft centerin' ring. Begad! Blimey! Blimey! Then a hole is drilled in t' center o' t' nuts, me bucko, through t' centerin' ring, takin' care t' use a small enough drill bit that t' threads aren't stripped. Well, blow me down! Aye aye! Blimey! Once dry, shiver me timbers, ya bilge rat, arrr, bolts are screwed into t' nuts and through t' plywood o' t' centerin' ring. T' clips are made from aluminium, ya bilge rat, arrr, bent t' shape by hammerin' them over, matey, while held in a vice. Arrr! Arrr! Blimey! T' unformed blanks were about 10mm wide and 35mm long.

Fins & Fin Pods

Fins & Fin Pods

After much sketching, shiver me timbers, 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, shiver me timbers, when viewed side-on. This neccessitated a four fin design, which was fine. Well, blow me down! Avast, ya bilge rat, me proud beauty! I reckoned I needed all t' stability I could get. Begad! It wasn't consistant with Tin Tin, arrr, but what t' hey, artistic license! Given t' flimsiness o' t' outer shell, shiver me timbers, t' fins have t' be through-the-wall. Aye aye! In t' end I descide t' make them pass through t' wall o' t' inner body tube too. Blimey! Begad! That way they can be securely mounted t' t' motor mount. Aye aye! This means that all t' major structural elements are glued t' each other, shiver me timbers, givin' maximum strength.

T' more I think about t' fins pods, t' more they seem like a nose cone, arrr, shiver me timbers, matey, but rounded at t' base, me bucko, ya bilge rat, where t' shoulder would normally be. Ahoy! I've had custom nose cones made before. Begad! I sketch a plan and get them made by Rockets & Things. I order five, ya bilge rat, one for emergencies! They arrive within a few days, shiver me timbers, and I'm well pleased, shiver me timbers, shiver me timbers, exactly t' right shape, shiver me timbers, and all identical. But how am I goin' t' attach them?

Rear view o' fins

Close up o' fin mounting

Rear view o' fins

While I ponder this I cut out t' fins from 3mm plywood. Ya scallywag! I leave a large tab for through-the-wall mounting. Arrr! I'm still wonderin' how t' mount t' pods. Ahoy! Blimey! Shouls I try t' slot them and slip them over t' fin? Tricky. Cut t' fin t' t' shape o' t' pod and make a butt-joint? Trickier. Well, blow me down! Begad! Blimey! Eventually I take t' brute force method and saw t' pods in half along their vertical axis. Begad! T' thickness o' t' saw takes about 1.5mm from t' diameter, ya bilge rat, measure at right angles t' t' cut. Avast, me proud beauty! A little sanding, required anyway t' level t' cut up a bit, matey, me bucko, removes 3mm in total. Well, blow me down! Begad! Blimey! When placed on either side o' t' fin, ya bilge rat, they are back t' t' original diameter. Blimey! Avast! Blimey! 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. Ahoy! Avast, me proud beauty! I use several coats o' sandin' sealer, with a light sandin' o' 120 grit betwixt coats. Blimey! Next I fill t' joins. I've tried all kinds o' filler. P38, specialist modelling filler, shiver me timbers, Ronseal exterior wood filler all sorts, matey, shiver me timbers, and they all smell terrible! I found t' P38 dries too smartly and sets too hard. Avast, me proud beauty! T' modellin' filler is expensive and doesn't stick t' phenolic very well. Aye aye! I like t' Ronseal best, it was workable longer, and easier t' sand, me hearties, but heavy. Arrr! Arrr! I like t' fill t' spirals in phenolic tubin' with this. In t' end I use t' specialist modelling filler because it's light. Aye aye! 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. Begad! Avast! I apply a few light coats o' primer t' t' pods, sandin' betwixt coats.

Fin Assembly

To allow for through-the-wall mountin' o' t' fins, me bucko, I need t' cut fin slots in both t' inner body tube and t' outer body shell. Begad! Blimey! I use a Dremmel for this with a disc cutter. Well, blow me down! Blimey! T' slots in t' inner body tube are true closed slots for strength. I reason that it will be easier t' attach t' fins t' t' inner body tube, ya bilge rat, before t' outer body shell is fitted. If I do that I won't be able t' get t' outer body shell on, arrr, arrr, arrr, so I make those slots all t' way t' t' bottom. Arrr! Blimey! Arrr! Blimey! This reduces teh strength, me bucko, but t' body shell isn't really stuctural anyway. Avast, me proud beauty! Blimey! T' fins are slotted into place in t' inner body and epoxied t' t' motor mount. Aye aye! Blimey! Ahoy! Blimey! Epoxy fillets are made where t' fins attach t' t' motor mount, and on both t' inside and outside o' t' inner body. Ahoy! Blimey! Ahoy! Blimey! T' slots are longe enough t' stretch from t' forward centerin' rin' t' t' aft centerin' ring. This all adds strength, me hearties, but weight as well. Blimey! Blimey! Finally t' aft centerin' rin' is epoxied into position.

Nose Cone

I need a coupler tube that will fit into t' plastic tubin' o' t' inner body. I don't have any, so make a short tlength from t' same tubing. Arrr! 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. Aye aye! Is epoxy t' cut out strip t' t' back o' t' join for reinforcement. This tube is first superglued and then epoxied into t' nose cone.

Fully assembled

Fully assembled, aft view

Final Assembly

Just in time, matey, I realise that t' outer shell isn't goin' t' be strong enough t' attach a launch lug to, me hearties, without some form o' reinforcement. Arrr! I cut a small rectangulat slot in t' side o' t' body shell. Begad! I epoxy some plywood t' t' interior o' t' shell, behind t' slot. Ya scallywag! Begad! T' epoxy gunges through t' slot, and I use it t' fix t' launch lug in place.

T' body shell slips on easily, and is epoxied initially t' just t' forward end. Avast! Actually t' inner tube is glued t' t' centerin' rin' previously fixed into t' outer shell. Aye aye! Because t' aft and o' t' shell is flappin' about a bit, I tack it into place with CA. Begad! Then I apply a liberal application o' epoxy, t' t' aft end and also t' t' fin roots. Once it's all set, it gets sanded and filled. Arrr! T' epoxy fillets in t' fin roots turn out a bit rough, me hearties, so I rebuild t' fillets with Ronseal. Ya scallywag! Prime, sand, arrr, fill, sand, shiver me timbers, primne, sand, matey, me bucko, fill, sand, me hearties, matey, prime, sand. Or somethin' like that. Begad! It's ready. Blimey! I rub it down lightly with 200 grit wet and dry.

Swin' test

Because o' t' odd shape, I didn't trust t' stability factor given by Rocksim. In fact rocksim reckoned it wasn't stable by a mile. Aye aye! But you don't always need more than a calibre o' stability on a stubby rocket anyway. I still reckon I need nose weight, but what t' use? Lead would be good, me bucko, 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. One pees are quite heavy for their size. Well, blow me down! I add 200g o' weight t' t' nose. Avast, me proud beauty! 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, me bucko, nay when t' washin' is dryin' anyway. So I comandeer t' next door neighbours garden, because they're nay in. Avast, me proud beauty! Needless t' say they came home durin' t' swin' test, but they're used t' it by now. Ahoy! Avast! Anyway I start t' swing, and it jumps into t' right orientation. Blimey! Great. I do a few more sims, shiver me timbers, usin' different motors, and it doesn't go very high. Aye aye! So I reduce t' nose weight t' about 100g, matey, or t' be more exact 31p. Avast! Avast! Another quick swin' test and it's still good. I blue t' nose wight into t' nose with epoxy. Blimey! Once t' epoxy is dry I realise that I have no where t' attach t' shock cord to. I drill a hole into t' nose weight, fill it with epoxy, and insert an eye hook. Well, blow me down! Well, me hearties, blow me down! Sorted.

Primed

Primed, aft view

Painting

Finish

I had been primin' as I went along, arrr, me bucko, so as soon as t' fin fillets were complete, shiver me timbers, it only took another couple o' coats t' get a nice smooth finish. Well, blow me down! T' primer used throughout is Halfords car paint, matey, ya bilge rat, in t' aerosol cans. Ya scallywag! I also use Halfords for t' main colours. Well, blow me down! Rover Diamond White and Volkswagen Mars Red. Blimey! Seems appropriate really. Aye aye! First I spray t' whole rocket white. Avast! I do about 3 coats, matey, lightly sandin' betwixt each. I had decided much earlier on that a full Tin Tin chequerboard was far too much work, ya bilge rat, so I had scaled t' pattern down t' two bands, o' four quadrants. Ya scallywag! Arrr! First I masked off every thin' above t' fins, me bucko, and painted everythin' below red. I also painted t' nose cone. Avast! T' red covered really well in only two light coats. Begad! Arrr! Next I painted t' two red quadrants o' t' lower band. So far so good. Aye aye! Begad! T' red quadrants o' t' upper band were hardest, bacause it be hard t' get a t' maskin' tape into exactly t' right position t' make t' square corners o' red meet exactly. Begad! T' maskin' was t' hardest part o' t' entire project. Avast, me proud beauty! Aye aye! T' red paint crept underneath t' tape in certain areas, me bucko, and in other areas t' tape lifted off some small areas o' white when removed. Ya scallywag! But I managed t' touch those defects up, me hearties, and I'm pretty pleased with t' final outcome. It's t' best finish o' all t' rockets I've made so far. Begad! Begad! It needs goin' over with 400 grit wet and dry and a coat o' lacquer applying, but thar's no time. Arrr! UKRA 2000 starts tomorrow!

Flight Test

I use about 150mm o' Nomex® sheath over t' nylon strap, and a Nomex® sheet above that t' protect t' chute. Avast, me proud beauty! Avast, me proud beauty! About 70mm o' 20mm elastic attach t' nose cone t' t' nylon strap. Aye aye! Blimey! A 34" PML chute is atached t' t' elastic too. I decide upon a G104 blue thunder reload. Begad! It's only just a G, but it gets t' rocket movin' quick. Aye aye! Blimey! I reckon t' sooner I can get it up t' stable speed t' better.

It rains on Friday and Saturday, shiver me timbers, and I'm hesitant t' fly. Well, blow me down! Sunday is better, me bucko, matey, and I decide t' fly before I take up spottin' duty. Ya scallywag! On t' Staryrday I'd had it on a rod, and found it was a little tight, but I had found a slightly smaller diametr rod, which was perfect. I be pretty nervous durin' t' countdown, and we had a hold for a low flyin' aircraft, but finally, ya bilge rat, shiver me timbers, t' moment comes. 5, matey, 4, 3, arrr, shiver me timbers, 2, arrr, 1 ignition. Ahoy! It's away! Great flight! It arced a bit after it left t' rod, but very smooth, no sign o' a wobble or instability o' any kind. T' ejection fired right at apogee, me hearties, and Tintinique drifted slowly down, shiver me timbers, landin' approximately 40" from t' pad. Ya scallywag! Ahoy! 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, arrr, me bucko, arrr, but I couldn't find t' piece chipped out so it probably happened in t' air. Begad! Easy t' fix, next flight comin' soon...

Nosecone damage