Tintinique

Tintinique

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

Nestlé time capsule

Centerin' rin' in position

Time Capsules

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

Anyway, me hearties, time passes and every time I go t' a launch thar's another time capsule. Avast! Blimey! I've got t' build this thing. Begad! I decide t' build it for RMR DesCon6. Time passes. Ya scallywag! Begad! DesCon6 begins. Arrr! Time passes. DesCon6 finishes. Avast! UKRA 2000 approaches, arrr, me bucko, and I realise that t' rocket I intended t' take, matey, shiver me timbers, arrr, Accusatory Finger o' Suspicion, me hearties, shiver me timbers, isn't goin' t' be ready. Begad! I dig out t' time capsule. Avast, me proud beauty! Blimey! I dig out cover scans o' t' books Destination Moon, ya bilge rat, shiver me timbers, and Explorers on t' Moon. Arrr! Well, blow me down! Blimey! 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. Well, blow me down! Time capsules are cheaply moulded, thick in some places thin in others, ya bilge rat, arrr, matey, and very flexible. I had decided that it was t' have a 29mm motor mount t' utilise t' short 29mm casings I had, shiver me timbers, and so t' body would need t' be reinforced. Ahoy! It needs an internal body tube, ya bilge rat, t' give structural strength and provide somethin' t' attach other components to, ya bilge rat, leavin' t' time capsule t' form only an outer shell. Avast! I had some 3" plastic tubin' that I had got from Ziggy at K-Lob, and this seemed ideal. Avast, me proud beauty! Begad! I could have used standard 3" PML phenolic, arrr, me hearties, 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, matey, shiver me timbers, and hacked a 3" diameter hole in t' base. Aye aye! T' openin' at t' top o' t' time casule was larger than 3", shiver me timbers, ya bilge rat, so I cut a 3mm thick plywood centerin' ring, and glued it in place, ya bilge rat, me bucko, matey, under t' shoulder. 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, arrr, me bucko, so I draw some rough sketches, then some rough, matey, arrr, dimensioned sketches. Avast, me proud beauty! My son, James, me bucko, ya bilge rat, draws some sketches. I'm nay really gettin' anywhere. Avast, me proud beauty! It's all free hand and nay very satisfactory. Begad! Well, me bucko, blow me down! Rocksim! T' time capsule is suprisingly easy t' describe usin' a parabolic nose cone, me hearties, and a couple o' eliptical transitions. Arrr! Now, shiver me timbers, Rocksim isn't really designed for this shape o' rocket, ya bilge rat, 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, 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. Ya scallywag! Blimey! I had originally intended for t' motor mount t' run t' length o' t' body, ya bilge rat, 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, matey, and anyway I don't have enough motor mount for t' full length o' t' internal body tube. Ya scallywag! Blimey! Avast! Blimey! So, I decide t' have a short motor mount, givin' t' full internal diameter o' t' internal tube for a parachute. Arrr! Blimey! I cut two, matey, 3mm thick, plywood centerin' rings that fit over t' motor mount and into t' plastic tube. Ahoy! Blimey! Begad! Blimey! T' forward centerin' rin' has a notch t' pass a nylon strap. Begad! Blimey! Arrr! Blimey! T' strap is about25mm wide and 400mm long. T' nylon strap will provide an attachment point for t' elastic shock cord. Ahoy! Blimey! Begad! Blimey! T' strap is t' epoxied t' t' inside o' t' internal body tube. Avast, me proud beauty! Blimey! Begad! Blimey! Throughout construction I use 5 minute or two ton Devcon epoxy.

T' forward centerin' rin' be epoxied t' t' forward end o' t' motor mount and allowed t' cure. Blimey! T' aft cebterin' rein' be fitted, with no epoxy, arrr, t' t' aft o' t' motor mount. Ya scallywag! T' forward centerin' rin' was epoxied into t' internal motor mount. Well, blow me down! Once t' forward centerin' rin' was fixed, t' aft centerin' rin' was removed. Well, ya bilge rat, blow me down! This gives access t' t' inside o' t' internal body tube, shiver me timbers, for filleting.

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

Fins & Fin Pods

Fins & Fin Pods

After much sketching, matey, 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. Begad! This neccessitated a four fin design, which was fine. I reckoned I needed all t' stability I could get. Aye aye! It wasn't consistant with Tin Tin, matey, ya bilge rat, but what t' hey, me bucko, ya bilge rat, shiver me timbers, artistic license! Given t' flimsiness o' t' outer shell, t' fins have t' be through-the-wall. Well, blow me down! In t' end I descide t' make them pass through t' wall o' t' inner body tube too. Avast, me hearties, 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, givin' maximum strength.

T' more I think about t' fins pods, me bucko, t' more they seem like a nose cone, shiver me timbers, me hearties, me hearties, but rounded at t' base, where t' shoulder would normally be. Avast, arrr, me proud beauty! I've had custom nose cones made before. Begad! Arrr! I sketch a plan and get them made by Rockets & Things. I order five, one for emergencies! They arrive within a few days, and I'm well pleased, exactly t' right shape, arrr, 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. Blimey! I leave a large tab for through-the-wall mounting. Avast, me proud beauty! I'm still wonderin' how t' mount t' pods. Blimey! Well, matey, blow me down! Shouls I try t' slot them and slip them over t' fin? Tricky. Arrr! 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. T' thickness o' t' saw takes about 1.5mm from t' diameter, shiver me timbers, ya bilge rat, measure at right angles t' t' cut. A little sanding, me hearties, required anyway t' level t' cut up a bit, me bucko, removes 3mm in total. Arrr! When placed on either side o' t' fin, me bucko, they are back t' t' original diameter. Begad! T' pod halves are simply glued t' either side o' a fin with carpenters glue, me bucko, clamped up and left t' dry.

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

Fully assembled

Fully assembled, aft view

Final Assembly

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

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

Primed

Primed, shiver me timbers, aft view

Painting

Finish

I had been primin' as I went along, me bucko, so as soon as t' fin fillets were complete, it only took another couple o' coats t' get a nice smooth finish. T' primer used throughout is Halfords car paint, arrr, me bucko, in t' aerosol cans. I also use Halfords for t' main colours. Avast! Rover Diamond White and Volkswagen Mars Red. Seems appropriate really. Well, blow me down! First I spray t' whole rocket white. Avast, ya bilge rat, me proud beauty! I do about 3 coats, shiver me timbers, lightly sandin' betwixt each. Avast! 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, ya bilge rat, o' four quadrants. Arrr! First I masked off every thin' above t' fins, and painted everythin' below red. Begad! I also painted t' nose cone. Ahoy! Aye aye! T' red covered really well in only two light coats. Aye aye! Next I painted t' two red quadrants o' t' lower band. Aye aye! So far so good. 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. Avast! Avast! T' maskin' was t' hardest part o' t' entire project. T' red paint crept underneath t' tape in certain areas, me hearties, and in other areas t' tape lifted off some small areas o' white when removed. Begad! But I managed t' touch those defects up, matey, and I'm pretty pleased with t' final outcome. It's t' best finish o' all t' rockets I've made so far. Avast, me proud beauty! Ya scallywag! It needs goin' over with 400 grit wet and dry and a coat o' lacquer applying, but thar's no time. Avast! 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. Begad! About 70mm o' 20mm elastic attach t' nose cone t' t' nylon strap. Begad! A 34" PML chute is atached t' t' elastic too. Avast, me proud beauty! I decide upon a G104 blue thunder reload. Aye aye! It's only just a G, arrr, arrr, 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, and I'm hesitant t' fly. Aye aye! Blimey! Blimey! Blimey! Sunday is better, and I decide t' fly before I take up spottin' duty. Well, blow me down! Blimey! 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 be perfect. I was pretty nervous durin' t' countdown, shiver me timbers, and we had a hold for a low flyin' aircraft, me hearties, but finally, t' moment comes. Ya scallywag! Blimey! Blimey! Blimey! 5, matey, 4, me hearties, 3, 2, me bucko, 1 ignition. Begad! Blimey! It's away! Blimey! Blimey! Blimey! Great flight! Blimey! Blimey! Blimey! It arced a bit after it left t' rod, but very smooth, ya bilge rat, shiver me timbers, no sign o' a wobble or instability o' any kind. Begad! Blimey! T' ejection fired right at apogee, me hearties, and Tintinique drifted slowly down, shiver me timbers, landin' approximately 40" from t' pad. Begad! Blimey! Aye aye! Blimey! Blimey! 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. Arrr! Blimey! Blimey! Blimey! Easy t' fix, ya bilge rat, next flight comin' soon...

Nosecone damage