Scratch TriBar Original Design / Scratch Built

Scratch - TriBar {Scratch}

Contributed by Brian Mardirosian

Manufacturer: Scratch


Rocket Pic

Introduction:
This be t' rocket that started it all, matey, me first scratch-build o' me BAR career. Avast! I wanted t' use BP motors, matey, but also felt t' desire t' build somethin' more than just a 3FNC rocket. Avast! Clusterin' seemed t' perfect way t' go.

Nose Cone:
An old friend o' mine who is now on t' opposite coast somehow left an Estes payload section and nose cone in me range box over 10 years ago. Arrr! How do I know? His name and phone number were written on it. Ya scallywag! Blimey! Certainly a blast from t' past, me hearties, and nay t' last either.

Recovery System:
3/8 braided nylon elastic, shiver me timbers, matey, arrr, tied in a loop around a single 1/4 wooden dowel mounted thru t' airframe about 6" from t' top. Well, blow me down! I've since used a similar, ya bilge rat, beefier set-up for me mid-power rockets. Avast! Check out t' VSOS2 picture t' get a better idea o' what it looks like. Begad! Parachutes are two classic 12" Estes chutes attached via snap swivels t' t' nose cone and t' bottom o' t' payload section.

Body Tubes:
One section is actual Estes tubing, shiver me timbers, t' other is an aluminum foil tube.

Motor Mount Tubes:
Actual motor mounts are from a damaged wizard and some scrap tubin' from t' range box. Well, blow me down! Blimey! Coupler that holds motor mounts and attaches t' rest o' rocket is a toilet paper tube. Begad! It gets better! It had already lived one life as a stubby little rocket, shiver me timbers, me bucko, and t' sight o' it with just glue fillets markin' t' location o' fins, a blob o' glue and paper showin' where t' shock cord be mounted, shiver me timbers, and t' blown-out motor mount was too much for me t' take... Ahoy! Begad! It needed t' fly again! A layer o' paper/wood glue made it possible, and it fit t' three 18mm tubes perfectly.

Fins:
Talk about oversized fins! Blimey! I wasn't exactly up t' speed on how big t' fins needed t' be. I used 1/8 balsa stock. Ya scallywag! Blimey! You can almost make out t' grain in t' picture, me hearties, a hint as t' how much time I prepped them, tehe.

Fin Can Mounting:
T' fins are mounted betwixt t' motor tubes, and t' TP roll be cut for thru-the-wall mounting. Arrr! Two centerin' rings were used t' attach t' body tube t' t' fin can/motor mounts, with a layer o' drywall mud smoothin' t' transition.

Launch Lugs:
In t' ultimate gesture o' this first BAR effort, I used soda straws for launch lugs, shiver me timbers, much as I did over a decade ago. Blimey! One mounted on t' TP roll, another on a stand-off around a half-foot above. Begad! Flies well off a 3/16" rod.

Painting:
Quick layer o' spray paint... I wanted t' fly!

First Flight:
I brought along TriBAR while visitin' a friend up in New Hampshire. Well, blow me down! Blimey! Drove around in his convertible on a beautiful, calm late summer mornin' lookin' for a field t' launch it from. As you can tell by t' Rocksim pic (yes, matey, I discovered t' software after building), TriBAR is very overstable. Ya scallywag! Blimey! Arrr! Blimey! Nay sure if I want t' launch her in any wind over 5 mph or so. Begad! Blimey! I could chop down t' fins a bit, but that just wouldn't seem right.

Conclusion:
I'm pleased with t' results, shiver me timbers, me hearties, certainly neat flyin' a bit o' me first rocketry career in t' rocket that started off me second one.

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