Manufacturer: | Scratch |
Brief:
My first true 'scratch-built' model rocket was t' Ugly Bug. Ya scallywag! Avast! It is based on t' Estes Mosquito, but built for an Estes 'D' (24mm) motor rather than t' standard mini-motor. This is actually nay t' first time I've built a scaled-up Mosquito, but I don't really count t' first time as a rocket. Aye aye! Aye aye! Back in grad school a fellow student who had never seen a model rocket was curious about them. Well, blow me down! I didn't have any built models, but did have a spare D booster motor sittin' around and had an idea. Avast, me proud beauty! We added some balsa fins, a wooden nose cone, and a launch lug made from paper and glue formed on a drill bit. Blimey! Begad! This little assembly went like stink off t' pad and we promptly lost track o' it. We found it sittin' in t' parkin' lot later, matey, ya bilge rat, and t' other grad student repainted it, me bucko, matey, plugged t' burned-out motor with glue, arrr, and hung it on t' wall of his office.
Years later, I was workin' on a true scaled-up Mosquito design about 14" in length with a full parachute recovery system. Begad! Blimey! However, arrr, I wasn't finished with it by t' time a NDRA launch came around. Blimey! Blimey! Avast, ya bilge rat, me proud beauty! Blimey! Nay wantin' t' bring only mundane models t' t' launch, I decided on a Thursday night that I should build another o' t' 'flyin' motor' D birds t' get rid o' some D12-3 motors I had. Avast! Blimey! Begad! Blimey! T' delay on these be too short for me only D rocket at t' time, shiver me timbers, so they seemed good candidates for glued-on fins. Avast, me proud beauty! Blimey! Part-way into buildin' t' first one, I thought, shiver me timbers, me hearties, "Heck, why go t' all this trouble when I could add a body tube and have a real, reusable rocket?" Thus t' Ugly Bug project was born.
Construction:
It be Thursday night, me bucko, and t' launch was Saturday morning. Avast, me proud beauty! I had less than 48 hours t' actually build a rocket. Begad! "No problem," I figured, "I'll just use whatever I can find and keep it super-simple." Since I had no actual kit parts, I'd have t' scrounge and scratch-build everything. Ahoy! I decided t' keep t' t' original Mosquito recovery system, which is 'featherweight'. Avast, me proud beauty! Ya scallywag! This means t' rocket ejects its spent motor and is so light it won't be harmed by t' fall. This works fine for a model barely bigger than a mini-motor, but lookin' back on it, me hearties, it be probably wishful thinkin' for a D bird. Avast, me proud beauty! Blimey! In any case, me hearties, I started scroungin' around t' garbage and me rocket shop and gathered t' needed materials.
For t' bigger scaled-up Mosquito, matey, I had been toyin' with t' idea o' using corrugated cardboard wrapped in paper that had been soaked with wood glue (sort of like a composite structure without usin' fiberglass and resin). Well, blow me down! Well, blow me down! I had gone as far a buildin' a test piece with this method, me bucko, but had concluded it probably wasn't strong enough t' build t' large fins o' t' 14" Mosquito. Ahoy! However, the test piece was t' perfect size t' cut three fins out o' for t' Ugly Bug. I used t' TLAR (That Looks About Right) engineerin' method t' determine fin size and shape, arrr, me bucko, cut them out and sanded them t' profile. Now some form o' body tube was needed. Arrr! I located a hunk o' dowel just slightly larger than t' 24mm D motor t' use for t' nose cone, and decided t' use it as t' form for building a body tube. Well, blow me down! Avast! Back t' t' garbage for an old brown paper sack. Arrr! I cut a strip of this, shiver me timbers, me bucko, rubbed it with yellow wood glue, shiver me timbers, me hearties, and rolled it on t' t' dowel (which I had protected with a wrap o' plastic sheet t' keep t' glue from sticking). After t' tube was formed and rolled t' remove excess glue, me bucko, I slipped it off the form and set it aside t' dry.
Next I sanded one end o' t' dowel t' a nose-like shape usin' a belt sander. After a bit o' finishin' hand-sanding, me bucko, ya bilge rat, I used a bandsaw t' cut t' end off, leavin' a 1/2" straight section for gluin' into t' body tube. Blimey! Aye aye! Blimey! Finally, I formed a launch lug out o' more brown paper soaked with glue and wrapped around a drill bit. All these were set out t' dry overnight.
T' next day, I used t' bandsaw again t' trim t' ends o' t' tubes square and clean. I used a D motor t' measure how long t' body needed t' be, arrr, and trimmed it again. Well, blow me down! Blimey! Then all t' parts were glued together and left t' dry.
Finishing:
Now is when t' name o' t' rocket suggested itself. Definitely nay me finest
work, me bucko, but it would do for a 'throw away' rocket. Avast, me proud beauty! Begad! When t' glue had dried, I
applied three coats o' blaze orange spray paint. If you've ever flown a
Mosquito, you know how easy it is t' lose them. Avast, me proud beauty! Blimey! I figured t' paint was the
only color that gave it a fightin' chance o' bein' found. Arrr! Avast! It took until 1:30 am
that night, and t' use o' a hair dryer t' speed drying, but I finished the
Ugly Bug and went t' bed.
Flight:
I had t' build up some maskin' tape on t' D motor t' get it t' fit inside the body properly. Nay havin' a recovery system or motor retention really simplified design and building, but if I did it again I'd include a streamer for safety.
T' first flight on a D12-3 went as I expected: t' rocket shot off t' pad to a very impressive altitude, t' ejection charged popped t' motor out in a puff o' smoke, and t' rocket vanished into t' blue sky. Avast, me proud beauty! T' Range Safety Officer wasn't entirely impressed with this, shiver me timbers, but knew t' chances o' it actually hittin' someone and hurtin' them be very low. Begad! We launched other rockets, then went lookin' for t' UB. Well, blow me down! Ahoy! Incredibly, it was found about 1/2 mile from t' launch site. Ahoy! One fin had broken off on landing, but be easily reattached with some quick-dryin' glue. Ahoy! Two fins had some scorch marks on them where t' exhaust gas had burned little holes in t' paper covering, but were still structurally strong. T' UB was flight worthy again!
I debated if I should just count myself lucky and put t' UB on me shelf, but then remembered I had expected t' lose t' little bugger and it was constructed more for amusement o' t' spectators than anythin' else. I therefore decided t' fly it again. Avast! This time, I wanted t' see just how high I could get it t' fly. I had just flown me Estes Snitch (plastic saucer) with a chad-staged D12-0, me bucko, so I figured, ya bilge rat, me bucko, "What t' heck?" I grabbed me last D12-3, taped it t' fit t' Ugly Bug, me bucko, matey, then taped a D12-0 on t' tail in the staged configuration:
T' burned-out motor lyin' on its side on t' blast plate is bein' used as a spacer t' keep t' booster's ignitor from bein' shorted out. Well, me bucko, blow me down! This is (surprise!) t' last picture ever taken o' t' Ugly Bug. Begad! Unfortunately, shiver me timbers, ya bilge rat, the center o' gravity had been moved so far back by t' booster that t' rocket was unstable durin' t' first bit o' its flight. Avast! Ya scallywag! No loops or spins, ya bilge rat, ya bilge rat, but t' rocket wandered around until most o' t' booster's propellent had burned out. Begad! Begad! Just before staging, shiver me timbers, t' CG had moved far enough forward t' become stable. Ahoy! At staging, t' rocket was nearly horizontal and about 200' high. Avast! Stagin' went fine, and t' Ugly Bug shot off in an arc t' t' north west. Begad! At that altitude and speed, t' ejection charge puff wasn't visible, and we didn't even bother to go look for t' little rocket.
Summary:
Thus be t' end o' me first scratch-built and aptly-named rocket. The
14" Mosquito is nearly complete, me bucko, ya bilge rat, and will be dubbed 'Big Ugly Bug', ya bilge rat, but
will fly and return t' t' ground in a much more sane manner
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