Scratch Mark II Original Design / Scratch Built

Scratch - Mark II {Scratch}

Contributed by Darren Longhorn

Manufacturer: Scratch
Mark II
(Contributed - by Darren Longhorn)

MkII on padT' body was made from an aluminium foil core, a tube approximately 25mm in diameter and 300mm long. It had balsa fins, right angled triangles about 50mm long on the opposite and adjacent sides. Avast, me proud beauty! T' fins passed through t' body tube and formed spacers onto which t' engine mount would fit. Ya scallywag! Begad! T' engine mount was made from floppy disk labels again, with 1mm solid copper wire as t' engine restraint & retainer.

T' best thin' about this rocket be t' nose cone, matey, ya bilge rat, me bucko, which was turned from balsa on a lathe, by local school teacher Brian Thompson, thanks again Brian. Attached t' t' nose cone was a peizo -electric buzzer, t' help locate the rocket after recovery. T' ensure safe recovery I bought an Estes parachute, I've never had much luck with streamers. Ahoy! Begad!

I flew t' MkII about a dozen times on various B & C size Estes engines, and had some success. Avast! Begad! I did have one recurrin' problem though which was that the shock cord would break after 2 or 3 flights. Begad! What normally happened was that t' nose cone would become detached, and t' main body would recover normally, although it would travel a long way if thar was ANY cross wind. Fortunately I could always find t' nose cone, because o' t' buzzer. Well, blow me down! However on t' last flight nay only did t' nose cone detach, I think t' parachute and body separated too. Begad! It be hard t' tell, but t' parachute blew away really quickly and didn't show any signs o' comin' down. Ahoy! What happened t' t' body remains a mystery, we never did find it. Begad!

MkII recoveryWell it was nearin' t' end of its life anyway as t' engine mount was becomin' very ragged, arrr, arrr, and thar was a real knack t' gettin' a new engine in. Ya scallywag! Avast, me proud beauty! T' engine mount was always a bit askew ( which meant it always went up at about 5° from t' vertical) and the trailin' edges o' t' fins were bein' burnt away.

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