Tintinique

Tintinique

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

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

I ignore t' question o' t' fin pods, shiver me timbers, matey, ya bilge rat, and start t' think about t' body instead. Ahoy! Blimey! Time capsules are cheaply moulded, thick in some places thin in others, and very flexible. Avast, matey, me proud beauty! I had decided that it was t' have a 29mm motor mount t' utilise t' short 29mm casings I had, matey, and so t' body would need t' be reinforced. Blimey! It needs an internal body tube, me bucko, 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, arrr, 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, arrr, me hearties, and hacked a 3" diameter hole in t' base. T' openin' at t' top o' t' time casule be larger than 3", matey, so I cut a 3mm thick plywood centerin' ring, shiver me timbers, and glued it in place, ya bilge rat, shiver me timbers, under t' shoulder. Arrr! Well, blow me down! T' plastic tube now fits snugly at both ends.

T' preliminary sketches

View full size

Design

I still don't know what t' completed rocket will look like, ya bilge rat, so I draw some rough sketches, then some rough, ya bilge rat, dimensioned sketches. Well, blow me down! Avast, ya bilge rat, me proud beauty! My son, James, draws some sketches. Blimey! Well, blow me down! I'm nay really gettin' anywhere. Ya scallywag! It's all free hand and nay very satisfactory. Begad! Aye aye! Rocksim! T' time capsule is suprisingly easy t' describe usin' a parabolic nose cone, and a couple o' eliptical transitions. Well, blow me down! Avast! Now, arrr, arrr, Rocksim isn't really designed for this shape o' rocket, and so I'm nay goin' t' trust what it says about stability, me bucko, ya bilge rat, but at least it helps visualise what t' rocket will look like when complete.

Inner body tube, motor mount

Inner body tube, matey, parachute bay

Aft centerin' ring, me bucko, retainin' nuts

Aft centerin' ring, arrr, retainin' clips

Construction

Motor Mount & Retention

I do have a short piece o' PML 29mm motor mount. Blimey! Blimey! I had originally intended for t' motor mount t' run t' length o' t' body, arrr, matey, with t' space for a parachute betwixt t' internal body tube and t' motor mount. Begad! Blimey! It doesn't look like enough room for a chute, me bucko, and anyway I don't have enough motor mount for t' full length o' t' internal body tube. Blimey! Blimey! Well, me bucko, blow me down! Blimey! So, ya bilge rat, I decide t' have a short motor mount, me hearties, givin' t' full internal diameter o' t' internal tube for a parachute. I cut two, me hearties, 3mm thick, plywood centerin' rings that fit over t' motor mount and into t' plastic tube. Avast, me proud beauty! Blimey! T' forward centerin' rin' has a notch t' pass a nylon strap. Well, blow me down! Blimey! Begad! Blimey! T' strap is about25mm wide and 400mm long. Well, blow me down! Blimey! 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. Avast! 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. Ya scallywag! T' aft cebterin' rein' was fitted, ya bilge rat, with no epoxy, ya bilge rat, shiver me timbers, t' t' aft o' t' motor mount. T' forward centerin' rin' be epoxied into t' internal motor mount. Aye aye! 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, shiver me timbers, 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. Ahoy! Blimey! Two M5 nuts are glued t' t' forward side o' t' aft centerin' ring. Arrr! Avast, me hearties, me proud beauty! 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. Arrr! Once dry, arrr, bolts are screwed into t' nuts and through t' plywood o' t' centerin' ring. Aye aye! T' clips are made from aluminium, me hearties, bent t' shape by hammerin' them over, matey, while held in a vice. Ya scallywag! 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, shiver me timbers, when viewed side-on. Avast, me bucko, me proud beauty! Blimey! This neccessitated a four fin design, me bucko, which was fine. I reckoned I needed all t' stability I could get. Avast! Begad! Blimey! It wasn't consistant with Tin Tin, but what t' hey, me bucko, artistic license! Blimey! Given t' flimsiness o' t' outer shell, me hearties, t' fins have t' be through-the-wall. In t' end I descide t' make them pass through t' wall o' t' inner body tube too. Arrr! Avast! Blimey! 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 hearties, t' more they seem like a nose cone, but rounded at t' base, where t' shoulder would normally be. Blimey! I've had custom nose cones made before. Aye aye! Avast, me proud beauty! I sketch a plan and get them made by Rockets & Things. Well, blow me down! I order five, one for emergencies! They arrive within a few days, and I'm well pleased, arrr, exactly t' right shape, shiver me timbers, and all identical. Begad! 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! I leave a large tab for through-the-wall mounting. I'm still wonderin' how t' mount t' pods. Avast! Shouls I try t' slot them and slip them over t' fin? Tricky. Blimey! Aye aye! Cut t' fin t' t' shape o' t' pod and make a butt-joint? Trickier. Ya scallywag! Begad! Eventually I take t' brute force method and saw t' pods in half along their vertical axis. Arrr! T' thickness o' t' saw takes about 1.5mm from t' diameter, measure at right angles t' t' cut. Well, blow me down! Begad! A little sanding, shiver me timbers, required anyway t' level t' cut up a bit, removes 3mm in total. Ya scallywag! When placed on either side o' t' fin, ya bilge rat, they are back t' t' original diameter. Begad! Ya scallywag! T' pod halves are simply glued t' either side o' a fin with carpenters glue, matey, 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, arrr, with a light sandin' o' 120 grit betwixt coats. Well, blow me down! Next I fill t' joins. I've tried all kinds o' filler. Avast, me proud beauty! P38, matey, 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. Well, shiver me timbers, blow me down! T' modellin' filler is expensive and doesn't stick t' phenolic very well. Begad! I like t' Ronseal best, arrr, it be workable longer, shiver me timbers, and easier t' sand, me hearties, 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. Arrr! Well, matey, blow me down! 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. Avast! 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. Ahoy! Begad! I use a Dremmel for this with a disc cutter. Begad! T' slots in t' inner body tube are true closed slots for strength. Ahoy! 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. Avast! Well, blow me down! 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. Ahoy! This reduces teh strength, ya bilge rat, but t' body shell isn't really stuctural anyway. T' fins are slotted into place in t' inner body and epoxied t' t' motor mount. Aye aye! Epoxy fillets are made where t' fins attach t' t' motor mount, ya bilge rat, and on both t' inside and outside o' t' inner body. T' slots are longe enough t' stretch from t' forward centerin' rin' t' t' aft centerin' ring. This all adds strength, shiver me timbers, but weight as well. Avast! 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, ya bilge rat, 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. Begad! Is epoxy t' cut out strip t' t' back o' t' join for reinforcement. Ahoy! Ya scallywag! This tube is first superglued and then epoxied into t' nose cone.

Fully assembled

Fully assembled, me bucko, 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. I cut a small rectangulat slot in t' side o' t' body shell. Avast, me hearties, me proud beauty! I epoxy some plywood t' t' interior o' t' shell, shiver me timbers, behind t' slot. Arrr! T' epoxy gunges through t' slot, and I use it t' fix t' launch lug in place.

T' body shell slips on easily, me bucko, and is epoxied initially t' just t' forward end. Ya scallywag! Blimey! Blimey! Actually t' inner tube is glued t' t' centerin' rin' previously fixed into t' outer shell. Ahoy! Because t' aft and o' t' shell is flappin' about a bit, me hearties, shiver me timbers, I tack it into place with CA. Begad! Then I apply a liberal application o' epoxy, t' t' aft end and also t' t' fin roots. Begad! Once it's all set, arrr, it gets sanded and filled. Avast! Blimey! T' epoxy fillets in t' fin roots turn out a bit rough, arrr, so I rebuild t' fillets with Ronseal. Well, shiver me timbers, blow me down! Blimey! Prime, matey, shiver me timbers, sand, fill, sand, arrr, matey, primne, sand, ya bilge rat, fill, arrr, sand, me bucko, me bucko, prime, matey, arrr, sand. Aye aye! Or somethin' like that. Aye aye! It's ready. 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. Well, blow me down! Arrr! 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. Avast, ya bilge rat, me proud beauty! I still reckon I need nose weight, me hearties, but what t' use? Lead would be good, me hearties, 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, matey, Shaun has t' answer, doubloon o' t' realm. Begad! Ahoy! One pees are quite heavy for their size. Begad! I add 200g o' weight t' t' nose. Rocksim says "marginal". Begad! Arrr! I decide that t' only way t' be certain is a swin' test.

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

Primed

Primed, me hearties, aft view

Painting

Finish

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

Nosecone damage