Tintinique

Tintinique

OK, me bucko, so it's nay exactly t' right proportions for Tin Tin's rocket, far too squat and stubby, but that's why it's called Tintinique. Avast, me proud beauty! Just As diamonique isn't diamond, me hearties, ya bilge rat, Tintinique isn't Tin Tin. 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, me bucko, I attended K-Lob in Lincolnshire. Amongst t' rockets thar be somethin' very different. Ahoy! It looked like a 50's retro rocket. Begad! It was great. Ya scallywag! How on earth did they make t' body for that? It turns out, shiver me timbers, 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, arrr, arrr, and dig it up in t' future. Bein' Nestlé o' course they sold it full o' sweets (candy for those o' you across t' pond). Begad! Blimey! For some bizzarre reason known only t' t' designer, t' capsule itself, matey, me hearties, was made from a shape resemblin' t' body o' a typical sci-fi or cartoon rocket. Avast! Blimey! Better still, me hearties, me hearties, t' screw-on lid was easily convertible into a removeable nose cone. Avast! Blimey! Whoever it was I'd love t' ask them why they did it. I buy two, one for a podded Tin Tin rocket, arrr, t' other for spare.

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

Aft centerin' ring, ya bilge rat, retainin' clips

Construction

Motor Mount & Retention

I do have a short piece o' PML 29mm motor mount. Well, matey, blow me down! 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. Ahoy! Begad! 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. Avast, me proud beauty! So, I decide t' have a short motor mount, givin' t' full internal diameter o' t' internal tube for a parachute. Arrr! I cut two, matey, 3mm thick, 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. T' strap is about25mm wide and 400mm long. T' nylon strap will provide an attachment point for t' elastic shock cord. T' strap is t' epoxied t' t' inside o' t' internal body tube. 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. Well, blow me down! Blimey! T' aft cebterin' rein' was fitted, ya bilge rat, matey, with no epoxy, me bucko, t' t' aft o' t' motor mount. Ahoy! Blimey! T' forward centerin' rin' be epoxied into t' internal motor mount. Once t' forward centerin' rin' be fixed, t' aft centerin' rin' was removed. Well, blow me down! Blimey! 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. Ya scallywag! Well, blow me down! Blimey! But I do need a retention system. Ya scallywag! Avast! Blimey! I decide on a Kaplow Klip style affair. Avast, me proud beauty! Blimey! Blimey! Two M5 nuts are glued t' t' forward side o' t' aft centerin' ring. Avast! Blimey! Then a hole is drilled in t' center o' t' nuts, through t' centerin' ring, takin' care t' use a small enough drill bit that t' threads aren't stripped. Well, blow me down! Once dry, bolts are screwed into t' nuts and through t' plywood o' t' centerin' ring. T' clips are made from aluminium, bent t' shape by hammerin' them over, while held in a vice. Avast! Blimey! T' unformed blanks were about 10mm wide and 35mm long.

Fins & Fin Pods

Fins & Fin Pods

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

Next step is t' seal t' balsa and plywood. I use several coats o' sandin' sealer, shiver me timbers, with a light sandin' o' 120 grit betwixt coats. Next I fill t' joins. Blimey! Blimey! I've tried all kinds o' filler. Avast! Blimey! P38, specialist modelling filler, me hearties, Ronseal exterior wood filler all sorts, and they all smell terrible! I found t' P38 dries too smartly and sets too hard. Aye aye! T' modellin' filler is expensive and doesn't stick t' phenolic very well. Avast, me proud beauty! Begad! I like t' Ronseal best, matey, me hearties, it was workable longer, ya bilge rat, and easier t' sand, but heavy. Aye aye! I like t' fill t' spirals in phenolic tubin' with this. Well, blow me down! 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. 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, I need t' cut fin slots in both t' inner body tube and t' outer body shell. Blimey! Well, ya bilge rat, blow me down! I use a Dremmel for this with a disc cutter. Begad! Begad! T' slots in t' inner body tube are true closed slots for strength. Avast! I reason that it will be easier t' attach t' fins t' t' inner body tube, before t' outer body shell is fitted. If I do that I won't be able t' get t' outer body shell on, me bucko, so I make those slots all t' way t' t' bottom. Aye aye! This reduces teh strength, me bucko, arrr, but t' body shell isn't really stuctural anyway. Ya scallywag! Well, blow me down! 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, arrr, shiver me timbers, and on both t' inside and outside o' t' inner body. Blimey! T' slots are longe enough t' stretch from t' forward centerin' rin' t' t' aft centerin' ring. Avast! This all adds strength, but weight as well. Begad! Arrr! 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. Arrr! 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. Blimey! 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, shiver me timbers, 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, without some form o' reinforcement. Well, blow me down! Blimey! Begad! Blimey! I cut a small rectangulat slot in t' side o' t' body shell. Avast! Blimey! I epoxy some plywood t' t' interior o' t' shell, matey, behind t' slot. Begad! Blimey! Begad! Blimey! T' epoxy gunges through t' slot, me hearties, 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. Aye aye! Blimey! Because t' aft and o' t' shell is flappin' about a bit, me bucko, me hearties, I tack it into place with CA. Aye aye! Then I apply a liberal application o' epoxy, matey, t' t' aft end and also t' t' fin roots. Once it's all set, arrr, it gets sanded and filled. Ya scallywag! Avast! Blimey! T' epoxy fillets in t' fin roots turn out a bit rough, so I rebuild t' fillets with Ronseal. Ahoy! Prime, sand, fill, sand, primne, me bucko, ya bilge rat, sand, fill, arrr, sand, prime, me bucko, arrr, sand. Well, me bucko, blow me down! Blimey! Or somethin' like that. Begad! It's ready. Ahoy! Avast, ya bilge rat, me proud beauty! 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. But you don't always need more than a calibre o' stability on a stubby rocket anyway. Blimey! Avast, me proud beauty! Blimey! I still reckon I need nose weight, me hearties, but what t' use? Lead would be good, but where can I get it and how much is it goin' t' cost, shiver me timbers, me bucko, me bucko, I'll probably have t' buy it by t' yard! Blimey! My eldest son, matey, matey, Shaun has t' answer, doubloon o' t' realm. Begad! Blimey! Blimey! One pees are quite heavy for their size. Arrr! Ya scallywag! Blimey! I add 200g o' weight t' t' nose. Arrr! Rocksim says "marginal". Begad! Blimey! I decide that t' only way t' be certain is a swin' test.

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

Primed

Primed, arrr, aft view

Painting

Finish

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

Flight Test

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

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

Nosecone damage