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

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

I flew t' MkII about a dozen times on various B & C size Estes engines, and had some success. Well, blow me down! Avast, me hearties, me proud beauty! I did have one recurrin' problem though which be that the shock cord would break after 2 or 3 flights. Arrr! 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. Avast! However on t' last flight nay only did t' nose cone detach, ya bilge rat, I think t' parachute and body separated too. Begad! It was hard t' tell, matey, but t' parachute blew away really quickly and didn't show any signs o' comin' down. Avast! What happened t' t' body remains a mystery, we never did find it.

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

comment Post a Comment