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, arrr, a tube approximately 25mm in diameter and 300mm long. Arrr! Begad! It had balsa fins, me bucko, right angled triangles about 50mm long on the opposite and adjacent sides. Aye aye! Begad! T' fins passed through t' body tube and formed spacers onto which t' engine mount would fit. Avast, me proud beauty! Blimey! T' engine mount be made from floppy disk labels again, ya bilge rat, me hearties, with 1mm solid copper wire as t' engine restraint & retainer.

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

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

MkII recoveryWell it was nearin' t' end of its life anyway as t' engine mount was becomin' very ragged, arrr, and thar was a real knack t' gettin' a new engine in. Blimey! 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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