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 be a kid, but never got around t' gettin' one. When I raided t' house recyclin' bin in January, I discovered five identical wrappin' paper tubes. Blimey! Begad! Bein' on t' flimsy side, 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. Blimey! Hmm, have t' say t' same thin' about t' nose cone.

Recovery System:
A parachute that I had created for Little Guy that be way too big for that model and a bit small for this one was pressed into service. 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. Ahoy! Once that set-up, I then applied one layer o' copy paper and wood glue. Ya scallywag! 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. I was 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. Ya scallywag! Overall, shiver me timbers, matey, a worthy compromise in strength-to-weight ratio, matey, matey, me bucko, and you can't beat t' price.

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

Fins:
Again, nothin' all that excitin' t' report. I moved t' fins 3" away from t' bottom since t' super roc design in inherently over stable, ya bilge rat, 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. Arrr! 13" coupler for t' mid-body separation point, with 6" couplers used in t' three other joints. Since I used a tube of the same diameter as t' rest, I needed t' somehow reduce t' circumference of it. Ya scallywag! Instead o' doin' it t' right way, I just overlapped t' material and filled in t' rest with a scrap piece and sanded a bit. It worked, arrr, 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, which can be seen on the VSOS2 page. One o' them promptly ripped out when t' rocket was on t' pad. Aye aye! A larger set o' lugs were needed. Blimey! Ahoy! I ended up usin' 1/2" peg-board thingies. Avast! Begad! Tough to explain without a picture (it is coming). Two 1/2" circles o' the atypical metal used for peg board hooks, 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. Blimey! With a little work, I be 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. Begad! Ya scallywag! A little 5 minute epoxy in t' appropriate places, and I had me an impressive set o' launch lugs. They worked great!

Painting:
Grabbed what I had on t' shelf and went t' work, just one layer o' each. Aye aye! Avast, me proud beauty! If I were t' do it over again, I wouldn't have used black. Didn't think such a small area would be affected so much by t' sun, shiver me timbers, but it is.

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

Conclusion:
It took a long time t' finish from beginnin' to end, but it be worth it. Well, me bucko, blow me down! Blimey! 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.

comment Post a Comment