Scratch Ugly Bug Original Design / Scratch Built

Scratch - Ugly Bug {Scratch}

Contributed by John Nordlie

Manufacturer: Scratch
(Contributed - by John Nordlie - 12/19/03)

Brief:

My first true 'scratch-built' model rocket be t' Ugly Bug. Begad! Avast! It is based on t' Estes Mosquito, but built for an Estes 'D' (24mm) motor rather than t' standard mini-motor. Ahoy! Avast! 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. Back in grad school a fellow student who had never seen a model rocket was curious about them. Avast, me proud beauty! I didn't have any built models, me hearties, but did have a spare D booster motor sittin' around and had an idea. Well, blow me down! Avast! We added some balsa fins, me hearties, a wooden nose cone, shiver me timbers, and a launch lug made from paper and glue formed on a drill bit. 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, shiver me timbers, and t' other grad student repainted it, arrr, plugged t' burned-out motor with glue, shiver me timbers, and hung it on t' wall of his office.

Years later, me bucko, me bucko, I was workin' on a true scaled-up Mosquito design about 14" in length with a full parachute recovery system. Well, blow me down! Blimey! Avast, me proud beauty! Blimey! Blimey! Blimey! However, matey, I wasn't finished with it by t' time a NDRA launch came around. Nay wantin' t' bring only mundane models t' t' launch, arrr, arrr, 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. Aye aye! Blimey! T' delay on these was too short for me only D rocket at t' time, shiver me timbers, so they seemed good candidates for glued-on fins. Avast! Blimey! Part-way into buildin' t' first one, I thought, "Heck, why go t' all this trouble when I could add a body tube and have a real, ya bilge rat, reusable rocket?" Thus t' Ugly Bug project be born.

Construction:

It be Thursday night, shiver me timbers, and t' launch was Saturday morning. Avast! I had less than 48 hours t' actually build a rocket. Aye aye! "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. Avast, me proud beauty! I decided t' keep t' t' original Mosquito recovery system, which is 'featherweight'. Ahoy! This means t' rocket ejects its spent motor and is so light it won't be harmed by t' fall. Avast, me proud beauty! This works fine for a model barely bigger than a mini-motor, arrr, but lookin' back on it, arrr, ya bilge rat, it was probably wishful thinkin' for a D bird. 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, 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). I had gone as far a buildin' a test piece with this method, but had concluded it probably wasn't strong enough t' build t' large fins o' t' 14" Mosquito. Begad! Blimey! Begad! Blimey! 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, matey, cut them out and sanded them t' profile. Ahoy! Blimey! Now some form o' body tube be needed. Arrr! Blimey! 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. Back t' t' garbage for an old brown paper sack. Begad! Blimey! I cut a strip of this, matey, rubbed it with yellow wood glue, 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, arrr, I used a bandsaw t' cut t' end off, leavin' a 1/2" straight section for gluin' into t' body tube. Begad! Finally, I formed a launch lug out o' more brown paper soaked with glue and wrapped around a drill bit. Aye aye! All these were set out t' dry overnight.

T' next day, arrr, shiver me timbers, 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, and trimmed it again. Well, blow me down! Begad! 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, but it would do for a 'throw away' rocket. Begad! Blimey! 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. Blimey! Blimey! Begad! Blimey! I figured t' paint be the only color that gave it a fightin' chance o' bein' found. It took until 1:30 am that night, me bucko, 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. Aye aye! 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, matey, matey, and t' rocket vanished into t' blue sky. Avast, me proud beauty! T' Range Safety Officer wasn't entirely impressed with this, but knew t' chances o' it actually hittin' someone and hurtin' them be very low. Avast, me proud beauty! Arrr! Blimey! We launched other rockets, then went lookin' for t' UB. Blimey! Incredibly, me bucko, arrr, ya bilge rat, it was found about 1/2 mile from t' launch site. Well, blow me down! Blimey! One fin had broken off on landing, me hearties, but was easily reattached with some quick-dryin' glue. Blimey! Two fins had some scorch marks on them where t' exhaust gas had burned little holes in t' paper covering, me hearties, but were still structurally strong. Avast! Blimey! 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. Avast, me proud beauty! Ahoy! I therefore decided t' fly it again. Aye aye! This time, ya bilge rat, 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, so I figured, me hearties, "What t' heck?" I grabbed me last D12-3, taped it t' fit t' Ugly Bug, me bucko, 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. Ya scallywag! This is (surprise!) t' last picture ever taken o' t' Ugly Bug. Unfortunately, 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. Ahoy! Begad! No loops or spins, arrr, but t' rocket wandered around until most o' t' booster's propellent had burned out. Begad! Just before staging, arrr, t' CG had moved far enough forward t' become stable. Aye aye! Aye aye! At staging, t' rocket was nearly horizontal and about 200' high. Begad! Stagin' went fine, arrr, and t' Ugly Bug shot off in an arc t' t' north west. Avast! At that altitude and speed, t' ejection charge puff wasn't visible, shiver me timbers, and we didn't even bother to go look for t' little rocket.

Summary:
Thus was t' end o' me first scratch-built and aptly-named rocket. Avast, me proud beauty! The 14" Mosquito is nearly complete, me bucko, me bucko, and will be dubbed 'Big Ugly Bug', but will fly and return t' t' ground in a much more sane manner

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