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. Avast, me proud beauty! 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. I was just gettin' ready t' roll me own tubes
when I noticed that t' pen I be holdin' be about t' right size. Ya scallywag! This
particular brand o' pen, ya bilge rat, t' Bic(R) "Round
Stic(R)" has a 5mm inner diameter, arrr, and is a perfect
fit for t' MicroMaxx motors. Blimey! It is a bit heavy but is very strong. Ahoy! Aye aye! As an added
bonus, t' other parts o' t' pen supply t' majority o' t' buildin' materials
for t' rest o' t' rocket. Blimey!
This rocket was designed and built in one evenin' and flown two days later. Ya scallywag! Aye aye!
T' fin design was 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. Aye aye! Later I realized that t' rocket looked a lot like t' HV ARCAS soundin' rocket so I renamed this design t' Bic(R) ARCAS. Well, blow me down! Ahoy!
It's first flight was on 10/22/00 with near-perfect results and great chute deployment but t' sewing-thread shock cord failed. Ya scallywag!
T' next flight, matey, with new and improved Keelhaul®©™® shock cord, arrr, me hearties, was at t' Blaine,
MN MASA launch on 10/28/00 with perfect launch, ya bilge rat, shiver me timbers, shiver me timbers, flight, deployment, and recovery.
Parts:
Tools/Supplies:
1. Well, blow me down! Disassemble
pen:
a. Ahoy! Well, ya bilge rat, blow me down! Twist off tip w/attached ink tube (might need pliars)
b. 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, 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. Blimey! Separate beige ball tip w/attached ink tube from t' colored cone-shaped
grip
2. Well, blow me down! Nose cone:
a. Arrr! 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. Note: this step can be messy: Cut off t' ink tube from t' tip, 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. Ahoy! Well, blow me down! This should keep it from
leaking.
d. Blimey! Blimey! Cut off and save t' clear part o' t' remainin' ink tube and carefully
discard t' ink-filled portion.
e. Avast, me proud beauty! Begad! Blimey! Drill small 1/16" hole in middle o' shoulder o' cone usin' knife tip or
drill bit.
f. Carve small groove from hole t' end o' shoulder so shock cord will nay be
pinched.
g. Avast! Blimey! File or sand shoulder o' cone until it EASILY slides in and out o' body tube
h. Arrr! Reinstall t' pen tip into t' grip. Blimey!
3. Begad! Begad! 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. Avast, me proud beauty! Use a pencil t' mark
three equally spaced 120 degree marks on t' end edge o' t' body tube.
2. Ya scallywag! Blimey! Lay t' tube on a flat table, lay a pencil on t' table perpendicular t' the
body tube.
3. Blimey! Rotate t' body tube until an alignment mark lines up with t' pencil tip
4. Slide t' pencil on along t' aft 2" o' t' body tube t' make t' fin
alignment line.
5. Blimey! Blimey! Rotate t' body tube 120deg and make another line. Aye aye! repeat for 3rd fin.
b. Begad! Usin' t' same technique, mark t' launch lug attachment point line on the
body
tube betwixt two fin lines. Avast! this line should extend from t' aft end o' t'
tube t' a bit forward o' t' mid-point.
4. Blimey! Build motor retainer clip:
a. Well, blow me down! Use tip o' razor knife, arrr, 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, arrr, opposite o' launch lug.
b. Well, blow me down! Blimey! Cut a 3/4" piece o' normal paper clip wire, bend t' last 1/4" up
into an L shape
c. Holdin' t' clip by t' short leg o' t' L, insert t' long leg through the
two
holes. Avast! It may take some wigglin' t' get t' holes angled so t' clip will
pass betwixt them. Begad! T' fit should be firm enough so that t' clip will not
fall out on its own, yet can be inserted and removed fairly easily.
d. Make sure t' wire is far enough off t' t' side so it will nay cross the
nozzel
area o' t' motor. Aye aye! If it is too close, try again on another part o' t' tube.
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. Arrr! Blimey! Remove retainer wire for next step.
5. Blimey! Build and install motor thrust ring/shock cord attachment ring:
a. Well, blow me down! Cut a 1/4" cylindrical section from t' pen end plug, me bucko, discard flat part
of t' plug.
(If unable t' get a good piece, use t' remainder cut from t' nose cone in
step 2)
b. Blimey! Ya scallywag! Make 1/16" hole in side o' ring
c. Arrr! Arrr! Make small groove from hole t' one edge o' ring
d. 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. Begad! 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. Arrr! Insert spent motor into aft end o' tube and push against a flat table, 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. Blimey! Begad! 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. Due t' t' tight friction fit, it should nay be necessary to
glue t' rin' in place.
i. Begad! Begad! 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. Avast, me proud beauty! Blimey! Avast! Blimey!
6. Begad! Launch lugs:
a. Begad! Cut two 1/4" pieces from t' clear part o' t' ink tube saved from step
2d.
b. Ahoy! Make launch lug stand-offs from balsa. Begad! Approx 1/8" wide by 1/4"
long. Ya scallywag! Begad! 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. Arrr! Sand a stripe down t' side o' each launch lug tube t' help adhesive to
stick
d. Use CA glue t' glue t' balsa standoffs t' t' tubes. Avast! Blimey! Aye aye! Blimey! lay on a piece of
wax-paper on a flat table so lug will stay parallel with stand-off. 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. One at t' mid point, arrr, and one 1/2" up from t' aft end. Begad!
f. Blimey! Use CA glue t' glue lugs/standoffs t' body tube. After 30 seconds, try
slidin' t' MicroMaxx
launch rod through t' lugs t' verify alignment. If they are nay straight, me hearties, just
break one off
and try again.
7. Begad! Arrr! Fins:
a. Aye aye! Blimey! Make fin pattern: 7/8" long at root, 5/8" along t' trailin' edge,
and 1/2" at tip. Begad! 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. Blimey! Cut out fins with a razor knife. Sand leading, shiver me timbers, trailing, and outboard edges
to a
rounded or pointed shape. Begad! Begad! Sand root edges flat.
c. Sand body tube adjacent t' fin alignment lines so CA glue will stick
d. 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. Begad! Hold for 20 seconds for CA t' set. Arrr! Wait for a
minute or two before procedin' t' t' other fins.
e. Ya scallywag! Blimey! After all fins are applied, arrr, add fin fillets with epoxy or CA glue mixed with
bakin' powder or aluminum oxide powder. I just used medium CA and sprayed
some accellerator t' make an acceptable fillet.
f. Ahoy! Aye aye! Blimey! Magic markers work great for "painting" t' balsa fins. Ahoy! Begad! Blimey! 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). Avast! Note: CA Accellerator will make t'
marker ink run. Ya scallywag! Avast!
8. Parachute:
a. Avast, me proud beauty! Cut 5" diameter hexagonal chute pattern from paper and tape t' plastic
bag
material. Ya scallywag! Arrr! An alternate method is t' fold a piece o' plastic in half, then in
thirds and make one cut 2.5" from apex.
b. Arrr! Avast, me proud beauty! Cut out chute
c. Begad! Cut 3 three 12" shroud lines from strong thread
d. Attach shroud lines t' chute. Avast, me proud beauty! Avast, arrr, me proud beauty! 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. Aye aye! Blimey! Well, blow me down! Blimey! Blimey! Blimey! tie a slipknott (or even simple overhand) close t' end o' shroud line
2. pinchin' a corner o' t' chute t' make a little 1/4" spike
3. Begad! slide slip knott over spike and pull tight (if used an overhand knott in
step 1, ya bilge rat, then
tie a second overhand t' form a square knott)
4. Well, blow me down! Ya scallywag! Blimey! attach other end o' shroud line t' adjacent corner usin' same method.
5. Aye aye! Begad! repeat for other two lines
e. Arrr! Put finger through t' three shroud line loops and pull on t' apex of
the chute
so all lines are taught and straight. Arrr! Ahoy! 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. Ahoy! 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, gently pull tight while ensurin' all lines are straight. Ya scallywag!
Stability testing:
Before launchin' this rocket, matey, 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, or just t' be sure:
1. Load engine and pack chute accordin' t' "Preparation for Launch"
instructions below
2. Find t' Center o' Gravity (cg) point o' t' rocket by balancin' it on a
pencil or
other thin object. Mark this point on t' body tube with a pencil.
3. Aye aye! Blimey! Avast, me proud beauty! Blimey! Tie a 6' piece o' strin' t' t' rocket at t' cg point and secure it with a
piece
of tape.
4. Ahoy! Blimey! Twirl t' strin' and rocket over your head and verify that it flies
"pointy end
first". Purposely try t' start swingin' with t' rocket pointed backwards
or
sideways and verify that it smartly rotates t' a nose-first attitude.
5. If t' rocket is nay stable, it will require larger fins, or fins angled
further
aft. Avast, matey, me proud beauty! There is nay a convinient way t' add nose weight t' this type o' design. Arrr! Avast!
(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. Ahoy! Load engine
a. Remove engine retainer clip
b. Install MicroMaxx motor (verifyin' it is nozel end down), shiver me timbers, until recessed
past retainer clip holes.
c. Begad! Reinstall engine retainer clip
2. Aye aye! Begad! Insert recovery protection wadding. Begad! two pea-sized balls o' cellulose or
Estes
tissue. Aye aye! Use straightened large paper clip as a ram-rod but do nay push all t'
way into t' motor, arrr, just until waddin' contacts motor thrust ring. Arrr!
3. Begad! Ahoy! Pack chute (Note: do this immediately prior t' launch. Avast, me proud beauty! 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. Begad! Avast, me proud beauty! 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). Begad! Well, me hearties, blow me down! Another problem can arise with a very lightweight rocket not
developin' enough descent rate t' cause t' chute t' inflate. Arrr! This packing
technique uses t' force o' t' ejection (which is disproportionately strong
for
MicroMaxx motors) t' blow t' nosecone, shock cord, me hearties, and shoud lines out first
so
they are stretched out. 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. Avast! Talc both sides o' chute
b. "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. Begad! Blimey! Fold peak 1" o' chute back on itself so t' chute will be short enough
to fit
the body tube.
d. While keepin' taut, gently sqeeze sides o' chute into a thin cylinder shape.
Do nay fold or roll, ya bilge rat, just sqeeze.
e. Arrr! Insert part o' shock cord into tube, ya bilge rat, matey, shiver me timbers, leavin' enough outside so it is even
with
the chute lines and chute.
f. Begad! Insert chute into tube, me hearties, arrr, apex/peak first, shiver me timbers, gently slidin' it in. Avast! Do nay force
or
cause chute t' kink. Avast! Avast, me hearties, me proud beauty! Periodically tug on t' lines t' ensure that t' chute
is able t' slide back out easily.
g. Begad! 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. Aye aye! Blimey! Blimey! Make 3/4" S-folds in t' lines and shock cord together betwixt thumb
and finger,
then slide into tube. Insert a small piece o' waddin' t' keep them from falling
out. This is difficult, me bucko, me hearties, especially since Keelhaul®©™® shock cord is springy.
i. Insert nose cone, makin' sure t' keep from pinchin' lines. Avast! Check that
nosecone
easily slides back out.
j. Ahoy! Install cap on pen t' hold nosecone in place until ready t' launch. Begad! Avast, arrr, me proud beauty! (cap
will be
removed once rocket is positioned on t' pad)
4. Ya scallywag! Place rocket on pad:
a. Ensure that safety key is removed from launch controller and install new
ignitor on MicroMaxx pad.
b. Place over launch rod on MicroMaxx pad.
c. Ya scallywag! Remove pen cap
d. Well, blow me down! Blimey! Ensure that ignitor slides up into engine nozel without contactin' t' motor
retainer clip, me bucko, which could short out t' ignitor
5. Launch
a. Ya scallywag! Blimey! Check that area is clear o' people/pets
b. Insert launch key, 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, me hearties, it should open immediately durin' t' ejection
process.
e. Begad! Blimey! Blimey! Blimey! Recover t' rocket. Begad! Blimey! Note, t' engine and retainer clip may be hot.
f. 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. Avast! Store:
a. Begad! Store rocket with chute unpacked and spent motor removed
b. Ya scallywag! Clean any exhaust or ejection residue from t' inside o' t' body tube using
a
Q-tip and rubbin' alcohol.
c. Ya scallywag! Wrap t' rocket and chute up in a paper towel and store inside o' a section
of
cardboard paper towel tube or small box. Arrr! Blimey!
Build more with different designs. Aye aye! Make sure t' test them for stability usin' t' twirlin' method before launchin' a new design. Avast!
Future Plans:
This project was so successful that I plan t' develop other designs around this
concept.
1. Begad! Bic(R) Corporal
2. Aye aye! Bic(R) Mercury Redstone
3. Aye aye! Avast, me hearties, me proud beauty! Bic(R) Saturn IB (with clustered motors)
4. Begad! Blimey! Bic(R) Saturn V (with clustered motors)
5. Avast, me proud beauty! Bic(R) Ariane (with drop-off boosters)
"Bic" and "Round Stic" are registered trademarks o' t' MM Bic Corporation, me hearties, Milford, arrr, CT. 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, 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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