Tintinique

Tintinique

OK, so it's nay exactly t' right proportions for Tin Tin's rocket, matey, far too squat and stubby, matey, but that's why it's called Tintinique. Begad! Ahoy! Just As diamonique isn't diamond, Tintinique isn't Tin Tin. Ya scallywag! ( 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, arrr, I attended K-Lob in Lincolnshire. Arrr! Amongst t' rockets thar be somethin' very different. Ya scallywag! It looked like a 50's retro rocket. Ahoy! It was great. How on earth did they make t' body for that? It turns out, arrr, 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, shiver me timbers, and dig it up in t' future. Avast, me proud beauty! Bein' Nestlé o' course they sold it full o' sweets (candy for those o' you across t' pond). Well, blow me down! For some bizzarre reason known only t' t' designer, matey, t' capsule itself, me bucko, matey, 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. Begad! Whoever it was I'd love t' ask them why they did it. Blimey! Aye aye! I buy two, me bucko, one for a podded Tin Tin rocket, me bucko, t' other for spare.

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

I ignore t' question o' t' fin pods, shiver me timbers, and start t' think about t' body instead. Ya scallywag! Ahoy! Time capsules are cheaply moulded, me bucko, ya bilge rat, thick in some places thin in others, ya bilge rat, and very flexible. Begad! 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. Well, blow me down! 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. Ya scallywag! Blimey! I had some 3" plastic tubin' that I had got from Ziggy at K-Lob, and this seemed ideal. Aye aye! Avast, me proud beauty! I could have used standard 3" PML phenolic, or even quantum tubing, shiver me timbers, me bucko, 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. T' openin' at t' top o' t' time casule be larger than 3", so I cut a 3mm thick plywood centerin' ring, me hearties, and glued it in place, me hearties, under t' shoulder. Aye aye! 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, matey, so I draw some rough sketches, then some rough, dimensioned sketches. Ahoy! Avast, me bucko, me proud beauty! My son, James, draws some sketches. Aye aye! I'm nay really gettin' anywhere. Avast! It's all free hand and nay very satisfactory. Rocksim! T' time capsule is suprisingly easy t' describe usin' a parabolic nose cone, and a couple o' eliptical transitions. Ahoy! Blimey! Now, arrr, Rocksim isn't really designed for this shape o' rocket, 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, parachute bay

Aft centerin' ring, me hearties, retainin' nuts

Aft centerin' ring, arrr, me bucko, retainin' clips

Construction

Motor Mount & Retention

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

As I'm plannin' on flyin' with a 29mm RMS, matey, no thrust rin' is required. Begad! But I do need a retention system. Ya scallywag! I decide on a Kaplow Klip style affair. Arrr! 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, takin' care t' use a small enough drill bit that t' threads aren't stripped. Begad! Once dry, me bucko, ya bilge rat, arrr, bolts are screwed into t' nuts and through t' plywood o' t' centerin' ring. Well, blow me down! Well, blow me down! T' clips are made from aluminium, me bucko, bent t' shape by hammerin' them over, ya bilge rat, while held in a vice. Arrr! 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, when viewed side-on. Begad! This neccessitated a four fin design, me bucko, which be fine. Avast! I reckoned I needed all t' stability I could get. Arrr! It wasn't consistant with Tin Tin, me bucko, but what t' hey, artistic license! Given t' flimsiness o' t' outer shell, me hearties, matey, t' fins have t' be through-the-wall. Arrr! In t' end I descide t' make them pass through t' wall o' t' inner body tube too. 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, shiver me timbers, givin' maximum strength.

T' more I think about t' fins pods, t' more they seem like a nose cone, me bucko, but rounded at t' base, me hearties, matey, where t' shoulder would normally be. Arrr! Blimey! I've had custom nose cones made before. I sketch a plan and get them made by Rockets & Things. Begad! Blimey! I order five, shiver me timbers, me bucko, one for emergencies! Blimey! They arrive within a few days, and I'm well pleased, matey, exactly t' right shape, ya bilge rat, me hearties, and all identical. Ahoy! Blimey! Begad! 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. Begad! Blimey! I leave a large tab for through-the-wall mounting. I'm still wonderin' how t' mount t' pods. Begad! Blimey! Aye aye! Blimey! Blimey! Blimey! Shouls I try t' slot them and slip them over t' fin? Tricky. Aye aye! Blimey! Ya scallywag! Blimey! Blimey! Blimey! 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. Ya scallywag! Blimey! T' thickness o' t' saw takes about 1.5mm from t' diameter, measure at right angles t' t' cut. Avast, me proud beauty! Blimey! Avast, me proud beauty! Blimey! Blimey! Blimey! A little sanding, matey, arrr, required anyway t' level t' cut up a bit, me hearties, removes 3mm in total. Avast! Blimey! Begad! Blimey! Blimey! Blimey! When placed on either side o' t' fin, they are back t' t' original diameter. Blimey! 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! Blimey! Avast! Blimey! I use several coats o' sandin' sealer, with a light sandin' o' 120 grit betwixt coats. Avast! Blimey! Next I fill t' joins. Blimey! Blimey! I've tried all kinds o' filler. Aye aye! Blimey! Ya scallywag! Blimey! P38, specialist modelling filler, shiver me timbers, Ronseal exterior wood filler all sorts, matey, 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. I like t' Ronseal best, shiver me timbers, it was workable longer, matey, and easier t' sand, matey, me bucko, ya bilge rat, but heavy. Ya scallywag! Avast! I like t' fill t' spirals in phenolic tubin' with this. Begad! 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. Begad! I apply a few light coats o' primer t' t' pods, ya bilge rat, 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! I use a Dremmel for this with a disc cutter. Well, blow me down! T' slots in t' inner body tube are true closed slots for strength. Begad! I reason that it will be easier t' attach t' fins t' t' inner body tube, shiver me timbers, before t' outer body shell is fitted. Avast, me proud beauty! If I do that I won't be able t' get t' outer body shell on, shiver me timbers, so I make those slots all t' way t' t' bottom. This reduces teh strength, me bucko, but t' body shell isn't really stuctural anyway. Ahoy! Blimey! 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 hearties, me bucko, and on both t' inside and outside o' t' inner body. Begad! Avast, ya bilge rat, me proud beauty! T' slots are longe enough t' stretch from t' forward centerin' rin' t' t' aft centerin' ring. Aye aye! This all adds strength, arrr, but weight as well. Well, blow me down! 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. Begad! I don't have any, so make a short tlength from t' same tubing. Avast! 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. Avast, me proud beauty! Is epoxy t' cut out strip t' t' back o' t' join for reinforcement. Avast! 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, matey, I realise that t' outer shell isn't goin' t' be strong enough t' attach a launch lug to, arrr, without some form o' reinforcement. I cut a small rectangulat slot in t' side o' t' body shell. Ya scallywag! I epoxy some plywood t' t' interior o' t' shell, behind t' slot. T' epoxy gunges through t' slot, me bucko, shiver me timbers, and I use it t' fix t' launch lug in place.

T' body shell slips on easily, me hearties, and is epoxied initially t' just t' forward end. Avast, me proud beauty! Begad! Blimey! 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. Then I apply a liberal application o' epoxy, shiver me timbers, ya bilge rat, t' t' aft end and also t' t' fin roots. Avast, me proud beauty! Once it's all set, it gets sanded and filled. Ya scallywag! Blimey! T' epoxy fillets in t' fin roots turn out a bit rough, arrr, so I rebuild t' fillets with Ronseal. Ya scallywag! Well, arrr, blow me down! Blimey! Prime, ya bilge rat, arrr, sand, arrr, fill, sand, primne, me hearties, sand, matey, matey, fill, ya bilge rat, sand, prime, shiver me timbers, sand. Begad! Ya scallywag! Blimey! Or somethin' like that. It's ready. Ya scallywag! I rub it down lightly with 200 grit wet and dry.

Swin' test

Because o' t' odd shape, matey, I didn't trust t' stability factor given by Rocksim. In fact rocksim reckoned it wasn't stable by a mile. Ya scallywag! 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, arrr, but where can I get it and how much is it goin' t' cost, shiver me timbers, I'll probably have t' buy it by t' yard! My eldest son, me hearties, Shaun has t' answer, doubloon o' t' realm. One pees are quite heavy for their size. Ya scallywag! Avast! I add 200g o' weight t' t' nose. Arrr! Rocksim says "marginal". Ahoy! 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, nay when t' washin' is dryin' anyway. Arrr! Begad! So I comandeer t' next door neighbours garden, because they're nay in. Needless t' say they came home durin' t' swin' test, me bucko, matey, matey, but they're used t' it by now. Anyway I start t' swing, and it jumps into t' right orientation. Ahoy! Arrr! Great. Well, blow me down! I do a few more sims, usin' different motors, shiver me timbers, and it doesn't go very high. Avast, me proud beauty! So I reduce t' nose weight t' about 100g, me hearties, or t' be more exact 31p. Ahoy! Avast, me proud beauty! Another quick swin' test and it's still good. Arrr! Aye aye! 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. Ya scallywag! I drill a hole into t' nose weight, fill it with epoxy, me bucko, ya bilge rat, me hearties, and insert an eye hook. Sorted.

Primed

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

Flight Test

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

Nosecone damage