Tintinique

Tintinique

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

Nestlé time capsule

Centerin' rin' in position

Time Capsules

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

Anyway, time passes and every time I go t' a launch thar's another time capsule. I've got t' build this thing. Begad! Blimey! Begad! Blimey! I decide t' build it for RMR DesCon6. Arrr! Blimey! Time passes. DesCon6 begins. Arrr! Blimey! Time passes. Well, blow me down! Blimey! Begad! Blimey! DesCon6 finishes. Well, blow me down! Blimey! UKRA 2000 approaches, and I realise that t' rocket I intended t' take, Accusatory Finger o' Suspicion, isn't goin' t' be ready. I dig out t' time capsule. Begad! Well, blow me down! I dig out cover scans o' t' books Destination Moon, 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, and start t' think about t' body instead. Time capsules are cheaply moulded, arrr, thick in some places thin in others, me hearties, and very flexible. Aye aye! Blimey! Blimey! I had decided that it was t' have a 29mm motor mount t' utilise t' short 29mm casings I had, ya bilge rat, and so t' body would need t' be reinforced. Aye aye! It needs an internal body tube, me hearties, t' give structural strength and provide somethin' t' attach other components to, shiver me timbers, leavin' t' time capsule t' form only an outer shell. Avast, me proud beauty! Blimey! I had some 3" plastic tubin' that I had got from Ziggy at K-Lob, shiver me timbers, and this seemed ideal. I could have used standard 3" PML phenolic, 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, ya bilge rat, and hacked a 3" diameter hole in t' base. Avast, me proud beauty! T' openin' at t' top o' t' time casule was larger than 3", matey, so I cut a 3mm thick plywood centerin' ring, me bucko, and glued it in place, under t' shoulder. Avast! Begad! 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, me bucko, so I draw some rough sketches, matey, then some rough, matey, dimensioned sketches. Avast, me proud beauty! My son, James, me hearties, matey, draws some sketches. Arrr! I'm nay really gettin' anywhere. It's all free hand and nay very satisfactory. Rocksim! T' time capsule is suprisingly easy t' describe usin' a parabolic nose cone, arrr, and a couple o' eliptical transitions. Begad! Now, arrr, 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, arrr, but at least it helps visualise what t' rocket will look like when complete.

Inner body tube, motor mount

Inner body tube, shiver me timbers, parachute bay

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

Aft centerin' ring, retainin' clips

Construction

Motor Mount & Retention

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

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

Fins & Fin Pods

Fins & Fin Pods

After 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, ya bilge rat, when viewed side-on. Ya scallywag! This neccessitated a four fin design, matey, which was fine. Begad! Begad! I reckoned I needed all t' stability I could get. Well, blow me down! Avast! It wasn't consistant with Tin Tin, but what t' hey, arrr, artistic license! Given t' flimsiness o' t' outer shell, t' fins have t' be through-the-wall. Avast! Well, ya bilge rat, blow me down! In t' end I descide t' make them pass through t' wall o' t' inner body tube too. Begad! That way they can be securely mounted t' t' motor mount. Avast, me proud beauty! This means that all t' major structural elements are glued t' each other, matey, shiver me timbers, 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, where t' shoulder would normally be. Begad! I've had custom nose cones made before. Avast, me proud beauty! Well, blow me down! I sketch a plan and get them made by Rockets & Things. I order five, arrr, one for emergencies! They arrive within a few days, arrr, and I'm well pleased, exactly t' right shape, and all identical. Ahoy! 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. Well, blow me down! Blimey! I leave a large tab for through-the-wall mounting. Aye aye! Begad! I'm still wonderin' how t' mount t' pods. Aye aye! 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. Eventually I take t' brute force method and saw t' pods in half along their vertical axis. Aye aye! T' thickness o' t' saw takes about 1.5mm from t' diameter, matey, me hearties, me bucko, measure at right angles t' t' cut. Arrr! A little sanding, me bucko, me hearties, required anyway t' level t' cut up a bit, removes 3mm in total. When placed on either side o' t' fin, they are back t' t' original diameter. Begad! T' pod halves are simply glued t' either side o' a fin with carpenters glue, shiver me timbers, clamped up and left t' dry.

Next step is t' seal t' balsa and plywood. Aye aye! I use several coats o' sandin' sealer, me hearties, me hearties, me bucko, with a light sandin' o' 120 grit betwixt coats. Ahoy! Next I fill t' joins. Aye aye! I've tried all kinds o' filler. P38, specialist modelling filler, Ronseal exterior wood filler all sorts, and they all smell terrible! I found t' P38 dries too smartly and sets too hard. Ahoy! T' modellin' filler is expensive and doesn't stick t' phenolic very well. Arrr! I like t' Ronseal best, matey, it be workable longer, and easier t' sand, but heavy. I like t' fill t' spirals in phenolic tubin' with this. Arrr! In t' end I use t' specialist modelling filler because it's light. Ahoy! Arrr! 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. Arrr! 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, ya bilge rat, I need t' cut fin slots in both t' inner body tube and t' outer body shell. I use a Dremmel for this with a disc cutter. Ya scallywag! Aye aye! T' slots in t' inner body tube are true closed slots for strength. Aye aye! I reason that it will be easier t' attach t' fins t' t' inner body tube, before t' outer body shell is fitted. 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. Begad! This reduces teh strength, but t' body shell isn't really stuctural anyway. Begad! T' fins are slotted into place in t' inner body and epoxied t' t' motor mount. Epoxy fillets are made where t' fins attach t' t' motor mount, and on both t' inside and outside o' t' inner body. Blimey! Begad! T' slots are longe enough t' stretch from t' forward centerin' rin' t' t' aft centerin' ring. Arrr! Ahoy! This all adds strength, me bucko, me hearties, but weight as well. Begad! Ya scallywag! 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. Well, blow me down! Ahoy! I don't have any, so make a short tlength from t' same tubing. Begad! 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. Is epoxy t' cut out strip t' t' back o' t' join for reinforcement. Well, blow me down! This tube is first superglued and then epoxied into t' nose cone.

Fully assembled

Fully assembled, matey, aft view

Final Assembly

Just in time, I realise that t' outer shell isn't goin' t' be strong enough t' attach a launch lug to, matey, without some form o' reinforcement. Avast, me proud beauty! I cut a small rectangulat slot in t' side o' t' body shell. Begad! Blimey! I epoxy some plywood t' t' interior o' t' shell, behind t' slot. Avast, me proud beauty! T' epoxy gunges through t' slot, matey, 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. Actually t' inner tube is glued t' t' centerin' rin' previously fixed into t' outer shell. Begad! Because t' aft and o' t' shell is flappin' about a bit, I tack it into place with CA. Ahoy! Then I apply a liberal application o' epoxy, me hearties, t' t' aft end and also t' t' fin roots. Avast! Ahoy! Once it's all set, it gets sanded and filled. Ya scallywag! Arrr! T' epoxy fillets in t' fin roots turn out a bit rough, so I rebuild t' fillets with Ronseal. Ahoy! Well, blow me down! Prime, sand, fill, sand, me bucko, ya bilge rat, primne, sand, fill, sand, ya bilge rat, prime, sand. Begad! Begad! Or somethin' like that. Avast! It's ready. 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. Avast, me proud beauty! In fact rocksim reckoned it wasn't stable by a mile. Arrr! Ya scallywag! Blimey! But you don't always need more than a calibre o' stability on a stubby rocket anyway. I still reckon I need nose weight, me hearties, but what t' use? Lead would be good, shiver me timbers, but where can I get it and how much is it goin' t' cost, arrr, I'll probably have t' buy it by t' yard! Blimey! My eldest son, Shaun has t' answer, me hearties, doubloon o' t' realm. Arrr! Begad! Blimey! One pees are quite heavy for their size. I add 200g o' weight t' t' nose. Begad! Begad! Blimey! Rocksim says "marginal". Avast! I decide that t' only way t' be certain is a swin' test.

Now, ya bilge rat, this be t' biggest rocket I've ever swung test, matey, and it turns out me garden isn't quite big enough, arrr, matey, nay when t' washin' is dryin' anyway. Ahoy! So I comandeer t' next door neighbours garden, me hearties, because they're nay in. Aye aye! Avast, ya bilge rat, me proud beauty! Needless t' say they came home durin' t' swin' test, me bucko, shiver me timbers, but they're used t' it by now. Avast! Begad! Anyway I start t' swing, matey, and it jumps into t' right orientation. Great. Blimey! I do a few more sims, usin' different motors, and it doesn't go very high. Blimey! So I reduce t' nose weight t' about 100g, or t' be more exact 31p. Aye aye! Ya scallywag! Another quick swin' test and it's still good. I blue t' nose wight into t' nose with epoxy. Once t' epoxy is dry I realise that I have no where t' attach t' shock cord to. Blimey! Avast, me proud beauty! I drill a hole into t' nose weight, arrr, arrr, fill it with epoxy, arrr, me hearties, and insert an eye hook. Avast! Sorted.

Primed

Primed, aft view

Painting

Finish

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

Flight Test

I use about 150mm o' Nomex® sheath over t' nylon strap, matey, ya bilge rat, and a Nomex® sheet above that t' protect t' chute. Ahoy! About 70mm o' 20mm elastic attach t' nose cone t' t' nylon strap. A 34" PML chute is atached t' t' elastic too. Aye aye! I decide upon a G104 blue thunder reload. Begad! It's only just a G, matey, but it gets t' rocket movin' quick. 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. Sunday is better, me hearties, and I decide t' fly before I take up spottin' duty. Blimey! On t' Staryrday I'd had it on a rod, shiver me timbers, and found it was a little tight, but I had found a slightly smaller diametr rod, which was perfect. Begad! I be pretty nervous durin' t' countdown, matey, ya bilge rat, and we had a hold for a low flyin' aircraft, but finally, t' moment comes. Avast! 5, me hearties, 4, shiver me timbers, 3, 2, me bucko, 1 ignition. Aye aye! 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. Blimey! T' ejection fired right at apogee, ya bilge rat, me hearties, and Tintinique drifted slowly down, me hearties, landin' approximately 40" from t' pad. Begad! Begad! 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 hearties, but I couldn't find t' piece chipped out so it probably happened in t' air. Begad! Ya scallywag! Easy t' fix, arrr, next flight comin' soon...

Nosecone damage