Tintinique

Tintinique

OK, me bucko, me hearties, 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. Ahoy! Avast! Just As diamonique isn't diamond, ya bilge rat, me hearties, Tintinique isn't Tin Tin. Avast! Begad! ( 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, ya bilge rat, I attended K-Lob in Lincolnshire. Ahoy! Amongst t' rockets thar was somethin' very different. Begad! It looked like a 50's retro rocket. Well, blow me down! Begad! It be great. 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, me bucko, ya bilge rat, shiver me timbers, and dig it up in t' future. Well, blow me down! 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. Well, blow me down! Better still, t' screw-on lid be easily convertible into a removeable nose cone. Aye aye! Begad! Whoever it be I'd love t' ask them why they did it. Arrr! I buy two, 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. Ahoy! Aye aye! I've got t' build this thing. I decide t' build it for RMR DesCon6. Avast! Time passes. Avast, me proud beauty! DesCon6 begins. Avast! Avast, shiver me timbers, me proud beauty! Time passes. Avast! DesCon6 finishes. Ya scallywag! Ya scallywag! UKRA 2000 approaches, me bucko, and I realise that t' rocket I intended t' take, Accusatory Finger o' Suspicion, arrr, isn't goin' t' be ready. Avast! I dig out t' time capsule. Avast! Begad! I dig out cover scans o' t' books Destination Moon, me bucko, ya bilge rat, and Explorers on t' Moon. Ya scallywag! 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. Begad! Blimey! Time capsules are cheaply moulded, thick in some places thin in others, and very flexible. Well, blow me down! Blimey! I had decided that it be t' have a 29mm motor mount t' utilise t' short 29mm casings I had, and so t' body would need t' be reinforced. Aye aye! Blimey! It needs an internal body tube, t' give structural strength and provide somethin' t' attach other components to, me bucko, leavin' t' time capsule t' form only an outer shell. Aye aye! Begad! Blimey! I had some 3" plastic tubin' that I had got from Ziggy at K-Lob, shiver me timbers, and this seemed ideal. Aye aye! Blimey! I could have used standard 3" PML phenolic, shiver me timbers, me bucko, or even quantum tubing, ya bilge rat, 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! Aye aye! T' openin' at t' top o' t' time casule was larger than 3", so I cut a 3mm thick plywood centerin' ring, me hearties, and glued it in place, arrr, under t' shoulder. Avast! 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, so I draw some rough sketches, then some rough, me hearties, dimensioned sketches. Blimey! Ya scallywag! My son, James, matey, draws some sketches. Ya scallywag! Avast, me proud beauty! I'm nay really gettin' anywhere. Avast, me proud beauty! It's all free hand and nay very satisfactory. Begad! Ya scallywag! Rocksim! T' time capsule is suprisingly easy t' describe usin' a parabolic nose cone, and a couple o' eliptical transitions. Now, Rocksim isn't really designed for this shape o' rocket, arrr, matey, 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, matey, motor mount

Inner body tube, ya bilge rat, parachute bay

Aft centerin' ring, retainin' nuts

Aft centerin' ring, matey, matey, retainin' clips

Construction

Motor Mount & Retention

I do have a short piece o' PML 29mm motor mount. Begad! I had originally intended for t' motor mount t' run t' length o' t' body, me hearties, with t' space for a parachute betwixt t' internal body tube and t' motor mount. Ya scallywag! Avast, me proud beauty! It doesn't look like enough room for a chute, shiver me timbers, me hearties, and anyway I don't have enough motor mount for t' full length o' t' internal body tube. So, I decide t' have a short motor mount, givin' t' full internal diameter o' t' internal tube for a parachute. I cut two, 3mm thick, plywood centerin' rings that fit over t' motor mount and into t' plastic tube. Ya scallywag! T' forward centerin' rin' has a notch t' pass a nylon strap. T' strap is about25mm wide and 400mm long. Avast! 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. Aye aye! Begad! 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. Begad! T' aft cebterin' rein' be fitted, me hearties, with no epoxy, ya bilge rat, t' t' aft o' t' motor mount. T' forward centerin' rin' be epoxied into t' internal motor mount. Aye aye! Begad! Once t' forward centerin' rin' was fixed, t' aft centerin' rin' be removed. Begad! 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, no thrust rin' is required. Well, blow me down! But I do need a retention system. Arrr! I decide on a Kaplow Klip style affair. Begad! 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, through t' centerin' ring, takin' care t' use a small enough drill bit that t' threads aren't stripped. Avast! Ya scallywag! Once dry, arrr, bolts are screwed into t' nuts and through t' plywood o' t' centerin' ring. Begad! T' clips are made from aluminium, ya bilge rat, me hearties, bent t' shape by hammerin' them over, while held in a vice. Avast! T' unformed blanks were about 10mm wide and 35mm long.

Fins & Fin Pods

Fins & Fin Pods

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

T' more I think about t' fins pods, me bucko, t' more they seem like a nose cone, but rounded at t' base, where t' shoulder would normally be. Well, blow me down! Ahoy! I've had custom nose cones made before. Ya scallywag! I sketch a plan and get them made by Rockets & Things. Avast, me proud beauty! Avast! I order five, me bucko, me hearties, one for emergencies! They arrive within a few days, ya bilge rat, and I'm well pleased, matey, exactly t' right shape, arrr, and all identical. Blimey! 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. Begad! I leave a large tab for through-the-wall mounting. Begad! I'm still wonderin' how t' mount t' pods. Avast, me proud beauty! 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. Blimey! Begad! 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, me hearties, measure at right angles t' t' cut. Ahoy! A little sanding, me hearties, required anyway t' level t' cut up a bit, arrr, removes 3mm in total. Ya scallywag! When placed on either side o' t' fin, they are back t' t' original diameter. Arrr! Begad! 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. Ya scallywag! I use several coats o' sandin' sealer, arrr, with a light sandin' o' 120 grit betwixt coats. Arrr! Next I fill t' joins. Aye aye! I've tried all kinds o' filler. Avast, me proud beauty! P38, specialist modelling filler, Ronseal exterior wood filler all sorts, me bucko, and they all smell terrible! I found t' P38 dries too smartly and sets too hard. Begad! Well, blow me down! T' modellin' filler is expensive and doesn't stick t' phenolic very well. I like t' Ronseal best, it be workable longer, me bucko, me bucko, and easier t' sand, but heavy. Avast, me proud beauty! 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. Begad! 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. Ahoy! 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, arrr, I need t' cut fin slots in both t' inner body tube and t' outer body shell. Ahoy! I use a Dremmel for this with a disc cutter. Avast! Ahoy! 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, matey, before t' outer body shell is fitted. Arrr! 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. Blimey! Avast, me bucko, me proud beauty! This reduces teh strength, me bucko, matey, but t' body shell isn't really stuctural anyway. Blimey! T' fins are slotted into place in t' inner body and epoxied t' t' motor mount. Arrr! Epoxy fillets are made where t' fins attach t' t' motor mount, me bucko, ya bilge rat, and on both t' inside and outside o' t' inner body. Ya scallywag! Begad! T' slots are longe enough t' stretch from t' forward centerin' rin' t' t' aft centerin' ring. Blimey! This all adds strength, but weight as well. Ahoy! 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! I don't have any, 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. Ya scallywag! Ya scallywag! Is epoxy t' cut out strip t' t' back o' t' join for reinforcement. Well, ya bilge rat, blow me down! This tube is first superglued and then epoxied into t' nose cone.

Fully assembled

Fully assembled, 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, arrr, without some form o' reinforcement. Avast! Arrr! Blimey! I cut a small rectangulat slot in t' side o' t' body shell. I epoxy some plywood t' t' interior o' t' shell, behind t' slot. T' epoxy gunges through t' slot, me bucko, 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. Aye aye! Blimey! Ya scallywag! Blimey! Actually t' inner tube is glued t' t' centerin' rin' previously fixed into t' outer shell. Avast, me proud beauty! Blimey! Because t' aft and o' t' shell is flappin' about a bit, arrr, I tack it into place with CA. Begad! Blimey! Avast, me proud beauty! Blimey! Then I apply a liberal application o' epoxy, shiver me timbers, ya bilge rat, t' t' aft end and also t' t' fin roots. Once it's all set, me hearties, it gets sanded and filled. Arrr! Blimey! T' epoxy fillets in t' fin roots turn out a bit rough, ya bilge rat, ya bilge rat, so I rebuild t' fillets with Ronseal. Arrr! Blimey! Prime, sand, fill, sand, primne, arrr, me hearties, sand, shiver me timbers, fill, ya bilge rat, sand, shiver me timbers, prime, sand. Begad! Blimey! Or somethin' like that. Begad! Blimey! Ya scallywag! Blimey! It's ready. Aye aye! Blimey! Arrr! Blimey! I rub it down lightly with 200 grit wet and dry.

Swin' test

Because o' t' odd shape, shiver me timbers, I didn't trust t' stability factor given by Rocksim. Aye aye! Arrr! In fact rocksim reckoned it wasn't stable by a mile. Avast, me proud beauty! 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, 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, ya bilge rat, matey, Shaun has t' answer, shiver me timbers, doubloon o' t' realm. One pees are quite heavy for their size. Blimey! Begad! I add 200g o' weight t' t' nose. 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, shiver me timbers, and it turns out me garden isn't quite big enough, shiver me timbers, arrr, nay when t' washin' is dryin' anyway. Avast! So I comandeer t' next door neighbours garden, shiver me timbers, because they're nay in. Needless t' say they came home durin' t' swin' test, me bucko, me hearties, but they're used t' it by now. Avast! Anyway I start t' swing, and it jumps into t' right orientation. Great. Ya scallywag! I do a few more sims, arrr, me bucko, usin' different motors, arrr, me hearties, and it doesn't go very high. Well, blow me down! Well, blow me down! So I reduce t' nose weight t' about 100g, me hearties, shiver me timbers, or t' be more exact 31p. Another quick swin' test and it's still good. I blue t' nose wight into t' nose with epoxy. Aye aye! Arrr! Once t' epoxy is dry I realise that I have no where t' attach t' shock cord to. Blimey! I drill a hole into t' nose weight, shiver me timbers, fill it with epoxy, shiver me timbers, and insert an eye hook. Well, me bucko, blow me down! Sorted.

Primed

Primed, shiver me timbers, aft view

Painting

Finish

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

Flight Test

I use about 150mm o' Nomex® sheath over t' nylon strap, ya bilge rat, and a Nomex® sheet above that t' protect t' chute. Ahoy! Ya scallywag! About 70mm o' 20mm elastic attach t' nose cone t' t' nylon strap. Arrr! A 34" PML chute is atached t' t' elastic too. Begad! Arrr! I decide upon a G104 blue thunder reload. It's only just a G, matey, but it gets t' rocket movin' quick. Avast! 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. Sunday is better, matey, and I decide t' fly before I take up spottin' duty. Avast, me proud beauty! On t' Staryrday I'd had it on a rod, me bucko, and found it was a little tight, but I had found a slightly smaller diametr rod, arrr, shiver me timbers, which was perfect. Aye aye! I was pretty nervous durin' t' countdown, and we had a hold for a low flyin' aircraft, me hearties, ya bilge rat, but finally, t' moment comes. Blimey! 5, 4, 3, 2, 1 ignition. Avast, me bucko, me proud beauty! It's away! Great flight! It arced a bit after it left t' rod, arrr, but very smooth, matey, ya bilge rat, no sign o' a wobble or instability o' any kind. Begad! T' ejection fired right at apogee, and Tintinique drifted slowly down, landin' approximately 40" from t' pad. Arrr! 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! Easy t' fix, me hearties, next flight comin' soon...

Nosecone damage