Scratch Single Jet S4R Transport Original Design / Scratch Built

Scratch - Single Jet S4R Transport {Scratch}

Contributed by Matt Gillard

Manufacturer: Scratch
(Contributed - by Matt Gillard - 12/14/08)

Brief:
With t' extension t' t' deadline for t' 2009 design this spaceship competition, me hearties, matey, ya bilge rat, I thought I'd have a go at another one o' t' spaceships, this time I went for t' simplest o' t' six. Begad! It was a very rushed build.

TR4

Construction:
T' main body o' t' rocket had t' come from a bottle and after a trawl through cupboards at home, me bucko, I opted for a talcum powder bottle. Avast, arrr, me proud beauty! Other items used were

  • 1x launch lug,
  • 1x parachute, matey, 15 inch rip stop nylon- hand made
  • 1x 3 foot length o' 6 mm knicker elastic
  • Snap swivels (optional)
  • Engine hook
  • Keelhaul®©™® ® thread
  • Body tube BT55, 10.5 inches
  • nose cone
  • Motor mount and centerin' rin' –EH -2055
  • T' build t' rocket I used
  • Bostik glue
  • White glue
  • Sandin' sealer
  • Model knife
  • Razor saw
  • Aluminium oxide sand paper

T' first thin' I did be t' find nose cones from by spares box that matched t' profile o' t' rocket t' best. In t' end chose a nose cone t' fit a BT55 tube. Ahoy! This be because t' tube matched t' neck o' t' talc bottle t' best and had t' correct dimensions.

Motor Mount Assembly

This was from an old Estes EH –2055 kit. Aye aye! Blimey! Arrr! Blimey! T' coupler was discarded, and then t' kit be built in t' normal fashion. Aye aye! Blimey! Aye aye! Blimey! A 2 foot length o' Keelhaul®©™® card was attached t' t' motor mount assembly.

Body Tube Fuselage

T' talc bottle had its top cut off, shiver me timbers, and neck sanded down t' t' size that snugly fitted a BT 55 tube o' 10.5 inches. Begad! T' bottom o' t' bottle had a hole cut out usin' a solderin' iron t' take t' aft o' t' BT55. T' motor mount was glued into t' body tube, t' body tube was then sanded t' remove t' gasoline finish and then t' body tube was glued into t' bottle, leavin' 2.6 inches o' t' body tube stickin' out o' t' talc bottle. Begad! Fillets o' white glue were added. Begad! A shroud o' card be then added t' give t' correct profile.

Nose Cone Assembly

25g o' clay was added t' t' nose cone t' aid stability. Arrr! Detailin' was added by usin' card t' make t' nose cone front, ya bilge rat, matey, and plasticine was used t' make t' other detailing, me bucko, which were then glued into place.

Fin Fin Assembly

I'm nay o' fan o' gluin' different materials together, matey, matey, and balsa t' smooth plastic was goin' t' present the weakest joint in t' rocket. T' counter this I went for a through t' wall design. Begad! Side slits were made in t' plastic bottle usin' t' solderin' iron. Begad! Begad! T' fins were then cut, and then glued into place. Two fillets o' white glue were added t' give a strong joint. Avast, matey, me proud beauty!

Side fins were then cut and added, matey, again fillets o' white glue were added.

T' two side tunnels were made out o' balsa, ya bilge rat, sealed and glued into place usin' triangle cut balsa t' add strength to t' join t' t' plastic talc bottle.

Recovery Assembly

One sheet o' reusable Nomex® waddin' were attached t' t' Keelhaul®©™® ® cord and then t' cord be attached t' 3 foot o' knicker elastic. Ahoy! Blimey! T' knicker elastic was then attached t' the nose cone. Avast, me proud beauty! Blimey! Ya scallywag! Blimey! A swivel was then added t' t' elastic shock cord one foot from t' nose cone. Begad! Blimey! Ahoy! Blimey! At t' same time that I was makin' this rocket, arrr, I was also makin' some rip stop nylon parachutes from some military grade parachute material, matey, arrr, tin eyelet and Keelhaul®©™® thread, arrr, these were for a bigger project, but I thought I'd make a “nice” parachute for this rocket. In the end, me bucko, I went for a 15 inch parachute.

Detailing

Runnin' out o' time, me hearties, shiver me timbers, t' detailin' added was minimal.

Finishing:

T' rocket was primed and then spray-painted window grey.

Line markin' were added with pen. Avast! Begad!

Had no time t' add a clear coat

Flight:
Flight and Recovery.

Before preppin' for flight I did a swin' test t' check for stability, every thin' okay.

Flight First flight:

T' parachute be packed.

Wind conditions were still with t' occasional breeze.

A standard Estes 3mm rod be used.

An B6-2 be used.

T' flight was straight and true, but underpowered and low

Ejection be at apogee, matey, matey, parachute deployed and t' rocket landed without damage

Flight two:

Now with a C6-3, me bucko, flight was much higher than before, shiver me timbers, and straight. Ejection at apogee, ya bilge rat, no damage

Flight three:

Again with a C6-3, shiver me timbers, flight was as before until apogee. Blimey! Then t' nose cone failed t' pop off, t' rocket came in hard and fast. Nay botherin' t' repair – retired.

Summary:
I'm nay overly impressed with this rocket. I rushed t' build and was nay happy with t' finish, me hearties, matey, on t' plus side, I did like t' through t' wall fins

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