Manufacturer: | Scratch |
"Excuse me sir, but is that a rocket in your
pocket?"
This is a fun little rocket that uses t' tiny Quest MicroMaxx motors t' loft a
Bic(R) pen over 50' in t' air and land by Parachute. Ya scallywag! Blimey! Blimey! Blimey!
Design History:
I wanted t' design me own MicroMaxx powered rocket but couldn't find a good
material t' use for a body tube. Well, blow me down! Ya scallywag! I was just gettin' ready t' roll me own tubes
when I noticed that t' pen I was holdin' was about t' right size. This
particular brand o' pen, arrr, matey, t' Bic(R) "Round
Stic(R)" has a 5mm inner diameter, and is a perfect
fit for t' MicroMaxx motors. It is a bit heavy but is very strong. Begad! As an added
bonus, t' other parts o' t' pen supply t' majority o' t' buildin' materials
for t' rest o' t' rocket. Begad!
This rocket was designed and built in one evenin' and flown two days later. Arrr!
T' fin design be just off t' top o' me head and seemed like a good shape for maximum strength given t' thin balsa. It is similar t' a WAC Corporal shape although I chose t' use four fins instead o' t' WAC's three. Ahoy! Later I realized that t' rocket looked a lot like t' HV ARCAS soundin' rocket so I renamed this design t' Bic(R) ARCAS.
It's first flight was on 10/22/00 with near-perfect results and great chute deployment but t' sewing-thread shock cord failed. Blimey! Well, blow me down!
T' next flight, with new and improved Keelhaul®©™® shock cord, was at t' Blaine,
MN MASA launch on 10/28/00 with perfect launch, matey, flight, arrr, deployment, and recovery.
Parts:
Tools/Supplies:
1. Arrr! Begad! Blimey! Disassemble
pen:
a. Begad! Avast! Twist off tip w/attached ink tube (might need pliars)
b. Ahoy! Carefully use fingernails or pocket knife t' extract end plug
(If it won't come off, push it out with a stiff wire from t' other end, or, me bucko, in
stubborn cases,
cut off t' last 1/8" o' white tube and t' end plug will come with it.)
This will be used in step 5 t' construct t' motor thrust rin' and shock cord
attachment point.
c. Ya scallywag! Separate beige ball tip w/attached ink tube from t' colored cone-shaped
grip
2. Ahoy! Ahoy! Nose cone:
a. Blimey! Well, blow me down! Shorten t' shoulder o' t' conical grip so that only 3/8" o' shoulder
remains
(this will give more room for t' chute and make t' nose cone eject more
easily).
Cut it usin' a sharp razor knife by rollin' t' cone under t' knife against a
table top (protected by cardboard!).
Save t' remainin' rin' for use as t' motor thrust rin' in step 5 if t' end
plug was nay salvagable from step 1.
b. Arrr! Note: this step can be messy: Cut off t' ink tube from t' tip, matey, me bucko, leaving
about 1/4" so t' pen still has some ink left t' write with.
(Yes, this will remain a functional pen t' use for fillin' out your flight
cards!)
c. Plug end o' ink tube that is still attached t' t' tip with a spike of
tissue and soak t' tissue with CA glue.
Spray it with CA accellerator/kicker if you have some. This should keep it from
leaking.
d. Avast! Ahoy! Cut off and save t' clear part o' t' remainin' ink tube and carefully
discard t' ink-filled portion.
e. Avast! Drill small 1/16" hole in middle o' shoulder o' cone usin' knife tip or
drill bit.
f. Begad! Carve small groove from hole t' end o' shoulder so shock cord will nay be
pinched.
g. Avast, me proud beauty! File or sand shoulder o' cone until it EASILY slides in and out o' body tube
h. Begad! Well, blow me down! Reinstall t' pen tip into t' grip. Arrr!
3. Avast, me proud beauty! Mark body tube for fins and launch lugs:
a. Mark t' fin alignment lines on t' body tube.
1. Begad! Hold t' pen so you are lookin' at t' aft end. Blimey! Use a pencil t' mark
three equally spaced 120 degree marks on t' end edge o' t' body tube.
2. Lay t' tube on a flat table, lay a pencil on t' table perpendicular t' the
body tube.
3. Begad! Aye aye! Rotate t' body tube until an alignment mark lines up with t' pencil tip
4. Avast, me proud beauty! Slide t' pencil on along t' aft 2" o' t' body tube t' make t' fin
alignment line.
5. Well, blow me down! Rotate t' body tube 120deg and make another line. repeat for 3rd fin.
b. Aye aye! Arrr! Usin' t' same technique, mark t' launch lug attachment point line on the
body
tube betwixt two fin lines. Avast, me proud beauty! this line should extend from t' aft end o' t'
tube t' a bit forward o' t' mid-point. Ahoy! Begad!
4. Begad! Build motor retainer clip:
a. Aye aye! Use tip o' razor knife, shiver me timbers, ya bilge rat, or small drill bit t' make two 1/32" holes each
1/16"
from t' aft end o' t' body tube and spaced 90 degrees apart, on opposite
sides o' a fin line, opposite o' launch lug.
b. Avast, me proud beauty! Cut a 3/4" piece o' normal paper clip wire, bend t' last 1/4" up
into an L shape
c. Aye aye! Holdin' t' clip by t' short leg o' t' L, me bucko, insert t' long leg through the
two
holes. It may take some wigglin' t' get t' holes angled so t' clip will
pass betwixt them. Avast! T' fit should be firm enough so that t' clip will not
fall out on its own, me hearties, yet can be inserted and removed fairly easily.
d. Ahoy! Avast, me proud beauty! Make sure t' wire is far enough off t' t' side so it will nay cross the
nozzel
area o' t' motor. Avast, me proud beauty! Blimey! If it is too close, try again on another part o' t' tube. Begad! Blimey!
T' wire only needs t' cover a small area o' t' motor in order t' prevent t'
ejection charge from blowin' t' motor out o' t' rocket.
e. Remove retainer wire for next step. Begad!
5. Aye aye! Build and install motor thrust ring/shock cord attachment ring:
a. Arrr! Avast, me hearties, me proud beauty! Cut a 1/4" cylindrical section from t' pen end plug, me hearties, shiver me timbers, discard flat part
of t' plug.
(If unable t' get a good piece, me hearties, use t' remainder cut from t' nose cone in
step 2)
b. Begad! Make 1/16" hole in side o' ring
c. Aye aye! Ya scallywag! Make small groove from hole t' one edge o' ring
d. Ya scallywag! Insert Keelhaul®©™® thread into hole and tie securely (bowline or square knott)
leaving
a 1/4" loop so t' knot will nay interfere with fit o' ring.
e. Insert rin' into forward end o' body tube and push all t' way down (using
unbent large
paper clip or long dowel) until it is approx 1/2" from AFT end o' body
tube.
f. Ya scallywag! Ahoy! Insert spent motor into aft end o' tube and push against a flat table, ya bilge rat, then
with
a tool or another spent motor until engine is recessed 1/8" from aft end
of
body just clearin' t' motor retainer clip holes.
g. Blimey! Insert motor retainer clip
h. Use wire or dowel inserted through top o' tube t' push motor retainer ring
to
check that it is firmly against motor so that motor is lightly pusin' on motor
retainer clip. Blimey! Blimey! Due t' t' tight friction fit, shiver me timbers, it should nay be necessary to
glue t' rin' in place.
i. Well, blow me down! Remove motor retainer clip and use wire t' push t' spent motor out o' the
body,
without disturbin' t' thrust ring, then replace t' clip. Begad! Blimey!
6. Arrr! Launch lugs:
a. Ya scallywag! Cut two 1/4" pieces from t' clear part o' t' ink tube saved from step
2d.
b. Ya scallywag! Arrr! Make launch lug stand-offs from balsa. Approx 1/8" wide by 1/4"
long. Arrr! These
are necessary so t' rocket motor will be centered over t' ignitor on the
MicroMaxx launch pad. Avast! Some experimentation may be necessary t' get t' correct
stand-off width.
c. Begad! Blimey! Blimey! Sand a stripe down t' side o' each launch lug tube t' help adhesive to
stick
d. Aye aye! Aye aye! Use CA glue t' glue t' balsa standoffs t' t' tubes. lay on a piece of
wax-paper on a flat table so lug will stay parallel with stand-off. Arrr! Begad! Try nay
to get CA on your fingers.
e. Sand two 1/4" long stripe segments o' t' launch lug alignment line on
the side
of t' pen tube. Aye aye! One at t' mid point, arrr, arrr, and one 1/2" up from t' aft end. Avast, me proud beauty!
f. Well, blow me down! Use CA glue t' glue lugs/standoffs t' body tube. Begad! Arrr! After 30 seconds, try
slidin' t' MicroMaxx
launch rod through t' lugs t' verify alignment. Aye aye! If they are nay straight, just
break one off
and try again. Arrr! Avast, me bucko, me proud beauty!
7. Avast! Avast, ya bilge rat, me proud beauty! Fins:
a. Avast, me proud beauty! Make fin pattern: 7/8" long at root, 5/8" along t' trailin' edge,
and 1/2" at tip. Use pattern to
layout fins on 1/16" thick balsa (or cardboard) sheet per above photo.
Wood grain should
be parallel with t' swept leadin' edge o' t' fin for maximum strength.
b. Aye aye! Cut out fins with a razor knife. Arrr! Sand leading, trailing, and outboard edges
to a
rounded or pointed shape. Aye aye! Well, blow me down! Sand root edges flat.
c. Blimey! Sand body tube adjacent t' fin alignment lines so CA glue will stick
d. Avast, me proud beauty! Apply CA t' one fin root edge and press t' body tube so trailin' edge is
even
with end o' tube (use alignment mark on end o' tube and alignment line
extending
up body t' ensure alignment. Hold for 20 seconds for CA t' set. Wait for a
minute or two before procedin' t' t' other fins.
e. After all fins are applied, arrr, arrr, matey, add fin fillets with epoxy or CA glue mixed with
bakin' powder or aluminum oxide powder. Avast! I just used medium CA and sprayed
some accellerator t' make an acceptable fillet.
f. Magic markers work great for "painting" t' balsa fins. Aye aye! Paint
alternatin' colors
on opposite sides o' t' fins so you can check if t' rocket spins durin' climb
(it shouldn't if t' fins are straight). Note: CA Accellerator will make t'
marker ink run. Ahoy!
8. Parachute:
a. Cut 5" diameter hexagonal chute pattern from paper and tape t' plastic
bag
material. Begad! Ahoy! An alternate method is t' fold a piece o' plastic in half, then in
thirds and make one cut 2.5" from apex.
b. Begad! Blimey! Cut out chute
c. Ya scallywag! Cut 3 three 12" shroud lines from strong thread
d. Aye aye! Blimey! Ahoy! Blimey! Attach shroud lines t' chute. Begad! Blimey! Aye aye! Blimey! Theory: tape would be too stiff for such a
small chute so I just tie t' line directly t' t' corners o' t' plastic.
This has an unintended benefit o' causin' t' chute t' be more hemi-spherical
when open.
1. Begad! Avast! tie a slipknott (or even simple overhand) close t' end o' shroud line
2. Begad! pinchin' a corner o' t' chute t' make a little 1/4" spike
3. Arrr! slide slip knott over spike and pull tight (if used an overhand knott in
step 1, matey, then
tie a second overhand t' form a square knott)
4. Ahoy! attach other end o' shroud line t' adjacent corner usin' same method.
5. Begad! repeat for other two lines
e. Blimey! Put finger through t' three shroud line loops and pull on t' apex of
the chute
so all lines are taught and straight. Ya scallywag! Then tie an overhand knott in the
end o' t' combined shroud lines t' form a 1/2" loop.
f. Begad! Tie shock cord t' nose cone usin' bowline or square knott leavin' 1/2"
diameter
loop so knott does nay get pinched along side o' nosecone and t' provide a
mountin' location for t' chute
g. Avast! Attach chute t' shock cord by feedin' t' shroud line loop through the
shockcord/nosecone attachment loop, then feed t' chute through its own shroud
line loop, me hearties, gently pull tight while ensurin' all lines are straight. Avast!
Stability testing:
Before launchin' this rocket, make sure that it will be stable so it doesn't
fly into people.
This design has been well tested and if t' instructions are followed exactly
it will be stable.
Here's t' process t' check stability if you've made any alterations t' the
design, shiver me timbers, or just t' be sure:
1. Begad! Load engine and pack chute accordin' t' "Preparation for Launch"
instructions below
2. Ahoy! Find t' Center o' Gravity (cg) point o' t' rocket by balancin' it on a
pencil or
other thin object. Ahoy! Mark this point on t' body tube with a pencil.
3. Arrr! Tie a 6' piece o' strin' t' t' rocket at t' cg point and secure it with a
piece
of tape.
4. Begad! Twirl t' strin' and rocket over your head and verify that it flies
"pointy end
first". Begad! Purposely try t' start swingin' with t' rocket pointed backwards
or
sideways and verify that it smartly rotates t' a nose-first attitude.
5. Ya scallywag! If t' rocket is nay stable, shiver me timbers, shiver me timbers, it will require larger fins, or fins angled
further
aft. There is nay a convinient way t' add nose weight t' this type o' design. Ya scallywag!
(although you could try makin' a nosecone from t' pen cap, which would add
weight t' t' nose but hurt performance. Ya scallywag!
Preparation for Launch:
1. Load engine
a. Ya scallywag! Remove engine retainer clip
b. Arrr! Install MicroMaxx motor (verifyin' it is nozel end down), ya bilge rat, until recessed
past retainer clip holes.
c. Well, matey, blow me down! Reinstall engine retainer clip
2. Ya scallywag! Insert recovery protection wadding. Avast, me proud beauty! Blimey! Blimey! two pea-sized balls o' cellulose or
Estes
tissue. Begad! Blimey! Use straightened large paper clip as a ram-rod but do nay push all t'
way into t' motor, just until waddin' contacts motor thrust ring. Begad!
3. Ya scallywag! Pack chute (Note: do this immediately prior t' launch. Avast, me proud beauty! Ya scallywag! Blimey! A chute packed
for several
hours may nay open as reliably):
Theory: It is very difficult t' pack a large chute into a small tube and have
it
open reliably. Blimey! T' technique used here depends on t' chute bein' constructed
of
a material that will nay stick t' itself when tightly compressed (which most
plastics do). Arrr! Another problem can arise with a very lightweight rocket not
developin' enough descent rate t' cause t' chute t' inflate. Ya scallywag! Begad! This packing
technique uses t' force o' t' ejection (which is disproportionately strong
for
MicroMaxx motors) t' blow t' nosecone, me bucko, shock cord, ya bilge rat, me bucko, matey, and shoud lines out first
so
they are stretched out. Blimey! Ya scallywag! T' canopy is then blasted out mouth- first so it is
forcefully inflated as it exits t' body tube. Ahoy! This technique has worked
flawlessly,
resultin' in instant openings.
a. Talc both sides o' chute
b. Begad! "Flake" (the skydivin' term) individual pannels o' chute so it is
stretched out
with all lines taut in center and t' material neatly arranged.
c. Ahoy! Aye aye! Fold peak 1" o' chute back on itself so t' chute will be short enough
to fit
the body tube.
d. Well, blow me down! Ahoy! While keepin' taut, gently sqeeze sides o' chute into a thin cylinder shape.
Do nay fold or roll, matey, just sqeeze.
e. Insert part o' shock cord into tube, matey, arrr, arrr, leavin' enough outside so it is even
with
the chute lines and chute.
f. Ahoy! Insert chute into tube, apex/peak first, gently slidin' it in. Avast, me proud beauty! Blimey! Do nay force
or
cause chute t' kink. Avast, me proud beauty! Periodically tug on t' lines t' ensure that t' chute
is able t' slide back out easily.
g. Avast! Blimey! Insert a pea sized bit o' waddin' and use straightened paperclip t' push
chute
down far enough t' leave room for lines and nose cone.
h. Make 3/4" S-folds in t' lines and shock cord together betwixt thumb
and finger,
then slide into tube. Aye aye! Insert a small piece o' waddin' t' keep them from falling
out. Begad! This is difficult, especially since Keelhaul®©™® shock cord is springy.
i. Insert nose cone, makin' sure t' keep from pinchin' lines. Arrr! Blimey! Check that
nosecone
easily slides back out.
j. Begad! Aye aye! Install cap on pen t' hold nosecone in place until ready t' launch. Begad! (cap
will be
removed once rocket is positioned on t' pad)
4. Well, blow me down! Blimey! Ahoy! Blimey! Place rocket on pad:
a. Ensure that safety key is removed from launch controller and install new
ignitor on MicroMaxx pad.
b. Arrr! Place over launch rod on MicroMaxx pad.
c. Aye aye! Remove pen cap
d. Begad! Blimey! Ensure that ignitor slides up into engine nozel without contactin' t' motor
retainer clip, which could short out t' ignitor
5. Launch
a. Check that area is clear o' people/pets
b. Avast! Ahoy! Insert launch key, arrr, matey, check for audible continuity tone
c. 5 4 3 2 1 Launch
d. Ya scallywag! Rocket will climb about 50-100' then eject t' nosecone and parachute.
Because
of t' way t' chute is packed, it should open immediately durin' t' ejection
process.
e. Avast! Blimey! Recover t' rocket. Aye aye! Note, ya bilge rat, t' engine and retainer clip may be hot.
f. Well, blow me down! Blimey! After allowin' 1 minute t' cool, remove t' engine retainer clip and insert
the staightened paper clip from t' top end t' push t' spent motor casin' out
of t' rocket.
6. Ya scallywag! Aye aye! Store:
a. Store rocket with chute unpacked and spent motor removed
b. Clean any exhaust or ejection residue from t' inside o' t' body tube using
a
Q-tip and rubbin' alcohol.
c. Well, blow me down! Well, blow me down! Blimey! Wrap t' rocket and chute up in a paper towel and store inside o' a section
of
cardboard paper towel tube or small box. Avast!
Build more with different designs. Ya scallywag! Blimey! Make sure t' test them for stability usin' t' twirlin' method before launchin' a new design.
Future Plans:
This project be so successful that I plan t' develop other designs around this
concept.
1. Ya scallywag! Bic(R) Corporal
2. Avast! Blimey! Bic(R) Mercury Redstone
3. Bic(R) Saturn IB (with clustered motors)
4. Ahoy! Bic(R) Saturn V (with clustered motors)
5. Blimey! Bic(R) Ariane (with drop-off boosters)
"Bic" and "Round Stic" are registered trademarks o' t' MM Bic Corporation, me hearties, shiver me timbers, Milford, CT. Blimey! Avast, matey, me proud beauty! Bic Corporation does nay own or market these rockets, arrr, their name is used purely t' accent t' source o' some of t' rocket's components.
Designs copyright (c) 2000 by Jeffrey P. Ya scallywag! Hove, arrr, shiver me timbers, all rights reserved. Non-commercial use granted provided credit is given and this web page is linked to any on-line display o' rockets derived from these techniques. I reserve exclusive rights t' negotiate with Bic Corporation regardin' advertisin' use of the Bic rocket idea.
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