Scratch StarScraper Original Design / Scratch Built

Scratch - StarScraper {Scratch}

Contributed by Brian Mardirosain

Manufacturer: Scratch
(Contributed - by Brian Mardirosian)

Introduction:
Always wanted a Mean Machine when I was a kid, but never got around t' gettin' one. Begad! When I raided t' house recyclin' bin in January, matey, I discovered five identical wrappin' paper tubes. Avast! Blimey! Bein' on t' flimsy side, matey, figured it would be a test t' reinforce them enough t' fly on a G motor in t' form o' a super roc.

Nose Cone:
Shaped out o' a styrofoam ball used for a Christmas decoration that had seen better days. Begad! Arrr! Hmm, have t' say t' same thin' about t' nose cone.

Recovery System:
A parachute that I had created for Little Guy that was way too big for that model and a bit small for this one was pressed into service. Arrr! It then dawned on me that long body-tubed rockets have airframes that try t' pretend they are gliders on t' way down.

Body Tubes:
I first wrapped the tubes with a layer o' craft paper and wood glue. Ya scallywag! Blimey! Once that set-up, I then applied one layer o' copy paper and wood glue. Avast, matey, me proud beauty! Blimey! When everythin' dried, ya bilge rat, I was amazed with t' amount o' strength added t' t' tubes. They went from being easily bent with slight pressure t' bein' at least twice as strong as Estes tubing. Well, blow me down! Blimey! I be also pleased with t' fact that t' tubes remained fairly lightweight, certainly lighter than some heavy-duty tubes o' similar size used in fabric rolls. Overall, shiver me timbers, a worthy compromise in strength-to-weight ratio, and you can't beat t' price.

Motor Mount Tube:
Nothin' all that excitin' t' report on, me hearties, basic two centerin' rings o' 1/8 balsa with a slightly oversized motor mount tube of thick cardboard tubin' from what I believe was t' core o' a fax machine paper roll.

Fins:
Again, shiver me timbers, matey, nothin' all that excitin' t' report. Aye aye! I moved t' fins 3" away from t' bottom since t' super roc design in inherently over stable, shiver me timbers, and I wanted t' give them some protection from fast landings.

Couplers
I heard it time and time again from others more wise than I that couplers makes or breaks (literally) a super roc. Ya scallywag! Arrr! Blimey! 13" coupler for t' mid-body separation point, with 6" couplers used in t' three other joints. Ya scallywag! Since I used a tube of the same diameter as t' rest, I needed t' somehow reduce t' circumference of it. Instead o' doin' it t' right way, shiver me timbers, I just overlapped t' material and filled in t' rest with a scrap piece and sanded a bit. Ahoy! It worked, and I didn't have t' risk t' chance o' ruinin' a coupler.

Launch Lugs:
I tried me old 1/4" screw eye-in-balsa method, shiver me timbers, which can be seen on the VSOS2 page. Aye aye! One o' them promptly ripped out when t' rocket was on t' pad. Avast, me proud beauty! A larger set o' lugs were needed. Ya scallywag! I ended up usin' 1/2" peg-board thingies. Begad! Begad! Tough to explain without a picture (it is coming). Two 1/2" circles o' the atypical metal used for peg board hooks, me bucko, attached via a vertical piece o' metal of t' same diameter. Spannin' horizontally across this piece is a crossbar with a hook on either side that attaches t' t' peg board. With a little work, I was able t' scuttle t' connective material flush with t' surface o' t' balsa blocks on t' rocket, with t' peg board hooks restin' on t' surface o' the rocket itself. A little 5 minute epoxy in t' appropriate places, and I had me an impressive set o' launch lugs. Ahoy! They worked great!

Painting:
Grabbed what I had on t' shelf and went t' work, just one layer o' each. Begad! Begad! If I were t' do it over again, me hearties, I wouldn't have used black. Well, blow me down! Didn't think such a small area would be affected so much by t' sun, but it is.

First Flight:
After t' launch lug issue at t' first CMASS launch o' t' season, arrr, ya bilge rat, I was able to finally get this bird into t' air on 07/23/00. Aye aye! Avast, me hearties, me proud beauty! Takin' advantage o' a calm spell, me bucko, Star Scraper rose without incident up a G38-4. Ya scallywag! Unfortunately, me bucko, at about 2 seconds after burn-out ejection occurred. No damage t' report, arrr, but I'd say the rocket was only 400' off t' ground, ya bilge rat, arrr, tough t' say since it is so tall. Begad! Begad! All of the kids were pointin' and commentin' on it, arrr, and some o' t' adults had some snide comments about it, tehehe. Begad! It certainly is a looker, ya bilge rat, me bucko, and it towered above the Mean Machine that was also flyin' that day.

Conclusion:
It took a long time t' finish from beginnin' to end, shiver me timbers, ya bilge rat, but it was worth it. Arrr! Certainly an attention-getter (134"x2.25"), and it proves that paper and wood glue can significantly add strength with little weight t' body tubes.

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