Scratch - Little Brute {Scratch}

Scratch Little Brute Original Design / Scratch Built

Scratch - Little Brute {Scratch}

Contributed by Matt Gillard

Manufacturer:

Brief:
This is me first attempt o' a scale change. Avast, me proud beauty! T' Big Brute is a rocket that I built a few years back but have never flown. With t' 2008 challenge callin' for a scale change on a rocket, shiver me timbers, me bucko, I thought I’d might as well get somethin' from t' original Big Brute. Lookin' through me collection o' nose cones, matey, t' only one with t' same profile as t' Big Brute be a 13mm diameter nose cone, t' rest o' t' scalin' followed givin' a minimum diameter tumble recovery small brute.

Construction:
Parts need

2.2" BT-5 body tube
Launch lug
1/16" balsa sheet
Nose cone from a defunct Estes fireflash - (P/N 072600, PNC-5A)
Clay mass

Also used be

Bostik glue
Pink spray paint
Pink paper
Black tape
A photocopier

T' scale from t' nose cone be t' be a 7.5 downscale which is about 13-14% o' t' original. Blimey! Blimey! This makes t' body tube t' be 2.2 inches long. Begad! T' fins were down scaled from t' original usin' a photocopier t' make a template. Aye aye! See EMRR featured tips on how t' do this.

scratch_littlebrute_onthepad Apart from that t' rocket builds itself. Begad! My major concern that unlike all t' min diameter 13mm rockets that I have flown in t' past, arrr, this rocket does nay has much in t' way o' aft fins that lower t' CP t' somewhere safe. T' 13mm motor really does lower t' CG, so I added 3g o' clay t' t' nose cone. Avast! I used Spacecad t' check things out and it came back okay.

T' whole rocket be painted pink t' match me original Big Brute, arrr, felt tip marker was used t' black out t' fins. Aye aye! Blimey! Begad! Blimey! Three strips o' black tape were added t' give t' strips. Avast! Blimey! Avast, me proud beauty! Blimey! T' name o' t' rocket, Little Brute be printed on pink paper and then glued into place. Ya scallywag! Blimey! Begad! Blimey! I could nay brin' myself t' put t' original name in such a small rocket.

Flight:
First flight be on a 1/2A3-4T motor. Aye aye! Take off was very fast. Ahoy! At about 100 feet it took a right angle turn and shot off sideways. Ahoy! On recovery, me bucko, t' little brute be nose cone buried and had stripped its launch lug. Aye aye! Blimey! Spacecad predicted 472 feet, me bucko, this flight was nowhere near that.

After gluin' a new longer lug, me bucko, two more flights were made a few days later on 1/4A3-3T motors. Arrr! Each time t' flight was arrow straight with no deviation from t' flight path seen. On each recovery t' little brute buried itself in t' soft earth. Arrr! spacecad version 3 does nay have t' 1/4AT motor profile. I imagine that version 4 does.

Summary:
Pro: It's small and I can get motors for it, unlike t' big brute where I have t' get an explosive license and have t' police visit me house every year t' see a wooden box.

Con: Ballistic recovery - never good.

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