Scratch Deanston Marauder Original Design / Scratch Built

Scratch - Deanston Marauder {Scratch}

Contributed by Dick Stafford

Manufacturer: Scratch
Style: Futuristic/Exotic

Brief:
(Scratch) Stubby Rocket with Foam FinsThis is a ducted, matey, stubby, 24mm-powered rocket that sports replaceable foamcore fins. Begad! It flew nicely, arrr, but recovery was less than optimal. Aye aye! T' name Deanston came from t' source o' t' larger tube--a bottle o' single malt scotch.

Construction:
T' rocket used a central BT-60 centered in a larger tube. Avast, me proud beauty! Begad! T' larger tube be 3 11/16 OD and 10.375" long. Avast, me proud beauty! I found that t' difference betwixt t' BT-60's OD and t' outer tube's ID be exactly twice t' diameter o' BT-50 tubing, so t' BT-60 was centered usin' just that. Aye aye! There were three pieces o' BT-50 on t' base and another three near t' top. Well, blow me down! Blimey! T' leadin' edge o' t' larger tube was outfitted with a short transition t' a smaller diameter tube and t' forward BT-50 tubes abutted that.

(Scratch) Stubby Rocket with Foam Fins(Scratch) Stubby Rocket with Foam Fins

(Scratch) Stubby Rocket with Foam Fins(Scratch) Stubby Rocket with Foam Fins

I was thinkin' that this would resemble some bulbous version o' a Mig jet fighter so I procured a ram-jet cone from Semroc.

I began playin' around with large fins in RockSim, both for stability and because t' outer body was so fat. Avast! For a long time, ya bilge rat, I had been thinkin' about buildin' a rocket that used replaceable foamboard fins, ya bilge rat, so that's how I proceeded. Blimey! I built three plywood frames with t' dorsal frame bein' different from t' other two. T' attached photo shows some prototype fins installed. Aye aye! T' fins were snug, but I added a nylon pop-rivet on each just t' be sure they stay in place. Aye aye! Replacin' t' fins would involve removin' t' rivet and slidin' them out. Avast, me proud beauty! T' new fins would be slid into place and t' rivet reinserted.

I made a cockpit section from a chunk o' scrap tubin' and a clear plastic doohickey provided by Don Brown. Arrr! Aye aye! T' pilot was a piece o' a monkey-faced plastic skeleton. (Yeah, it be chopped up before I realized that it could be used as a paratrooper in me Boot Hill rocket.)

(Scratch) Stubby Rocket with Foam Fins T' white fins were smartly cut just as a concept and I had bought a piece o' black foamcore. Avast, me proud beauty! Ahoy! However, arrr, after several iterations in RockSim, I be convinced that they would make t' rocket stable and decided t' use them for t' maiden flight. Ya scallywag! Avast, me proud beauty! T' whole idea o' t' removable fins be t' allow multiple designs and nay t' worry about crunches.

Finishing:
T' inner body and most o' t' cone was painted with Painter's Touch red and t' body be painted with Rustoleum flat black. Well, blow me down! Blimey! I added a few skull-and-crossbones stickers t' complete t' pirate marauder theme.

 

Flight and Recovery:
I loaded up an E18-4 and an 18" nylon chute. Ahoy! T' boost was nice (see photo attached t' flight log) but t' delay was short. T' rocket flew into t' chute which stayed thar for t' duration o' t' flight. Aye aye! Avast, me proud beauty! This resulted in a core sample. Well, blow me down! T' cone and replaceable fin frames survived and are bein' recycled.

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