Madcow Rocketry mini Aerobee 150A User manual

Specications:
Length: 28.9”
Diameter 1.6”
Weight: 8oz
Recovery: 18” Nylon Chute
Motor Mount: 29mm
Fins: 4 - 1/8” Plywood
CP: 22.1” from nose tip
CG: 20.5” from nose tip
Recommended Motors:
Single Use Reloadable
D12-5* 455’ E16W-7 1380’
E9-6 * 848’ E23T-6 1006’
F20W-7 2011’ F52T-8 2274’
F23J-7 1763’ G64W-10 3308’
G79W-10 3070’ 51F36-9 (BS) 1696’
*Requires 29/24 adaptor 57F59-9 (WT) 1859’
56F120-9 (VX) 1837’
41F36-7 (SS) 1349’
107G83-9 (BS)2994’
93G80-9 (SK) 2817’
Parts List
1. (1) Nose cone
2. (1) Body tube
3. (2) Centering rings
4. (1) 29mm motor tube
 5. (4)laser-cutns
6. (1) Kevlar® shock cord section
7. (1) Nylon shock cord section
 8. (1)6”x6”ameproofchuteprotector
9. (1) 18” Nylon chute
10. (2) ¼” launch lugs
11. (4) Balsa Sticks
Required to complete: 5 minute epoxy,
120/220sandpaper,maskingtape, nishing
ller/paint.
K-195
898666 00195 6
®
23016 Del Lago, Unit C, Laguna Hills, CA 92653
949.547.8847
www.madcowrocketry.com
©2015 MadCow Rocketry™
150A
mini

2 ©2015 MadCow Rocketry™ mini Aerobee 150A mini Aerobee 150A ©2015 MadCow Rocketry™ 3
Please make sure you read all directions and understand how to assemble your model
beforeyoustartconstruction.Itisalsoagoodideatotestteachpartbeforeassembly
–somemanufacturingtolerancesmayrequirelightsandingbeforenalassembly.
Laser cut parts will exhibit varying amounts of charring on the edges depending on the
density of the plywood. The charred edges do not interfere with bonding and do not
need to be cleaned before assembly. In most cases the charring will be cleaned up
duringsandingfornishingandpainting.
Step 1 – Motor Mount Assembly
Step 2 – Insert Motor Tube Assembly into Body Tube
Testteachofthensintotheprecutnslots.Becauseplywoodthicknessvaries,you
may need to sand the slot to the correct width. Wrap the shock chord into a small bundle
andstuffitinsidethemotortubeforthisnextstep.Testtthemotortubeassemblyinto
thebodytubetoensureasnugt.Sandthecenteringringsifnecessary.Whenyou
aresatisedwiththet,spreadsomeepoxyontheinsideofthebodytubeandslidethe
forward centering ring of the motor assembly into the body tube. Make sure you have
the motor assembly facing the right way! Spread some more epoxy on the inside
edge of the body tube before sliding the rear centering ring into the body tube. Continue
Ensureringsareclearofthenslots
sliding the assembly inside the body tube
until the aft centering rings are just clear
ofthenslots.It’sagoodideatotestt
anineachslotherebeforetheepoxy
sets. Hold the body tube with the motor
tube assembly down until the epoxy sets.
Make sure the weight of the motor tube
doesn’t cause it to slide out of alignment.
Step 3 – Fin Assembly
Using a door jam or small section of angle stock, pencil a line halfway between two of the
nsthatextendsfromthefronttothebackofthebodytube.Thislinewillbeusedlater
to align the launch lugs. Additionally, pencilalinefromthefrontofeachntothe
end of the tubes to aid in aligning the conduits later. Testteachofthensinto
theprecutnslots.Thenshouldseatrmlyagainstthemotortube-sandeachnor
slotifnecessary.Whenyouaresatisedwiththet,applysomeepoxytotheendofthe
ntangthatwillcontactthemotortube.Also,spreadathinlayerofepoxyoneachside
ofthentang.Slidethenintoplaceandcheckthealignment.Continuerechecking
thenalignmentuntilyouaresuretheepoxyhasset.Cleananyexcessepoxyfrom
aroundthenjoint.Repeatfortheremainingns.Next,applyepoxylletstobothsides
ofeachnbyapplyingathinbeadofepoxyatthen-bodytubejoing.Carefullysmooth
theepoxylletswithyourngerbeforetheepoxysets.Alloweachllettosetbefore
rotatingtheairframeforthenextllet.
Testtcenteringringsoverthemotormounttubeandsandmotortubeifnecessary.Also
testtthecenteringringsinthebodytubeandsandifnecessary.Spreadsomeepoxyon
the outside of one end of the motor tube and slide the ring (without the notch) until there
is approximately 1/2” of motor tube exposed. Make sure you clean the motor tube of any
epoxysoasnottointerferewiththentangslater.Aftertheaftringisdry,makeamark
1/2” from the other end of the motor tube. Spread some epoxy on the motor tube and
slide the forward ring until it aligns with the mark. VERY IMPORTANT: make sure there
is not any epoxy on the motor tube that would interfere with the n tangs later on.
Fin
Fin Tang
1/2” Exposed
1/2” Exposed
Forward Ring Notch
Push cord in corner and
tack with epoxy
The shock cord in this kit consists
of a shorter section of Kevlar and a
longer section of nylon cording. The
two sections should be tied together
using a single overhand, ring bend
ordoublesherman’sknot.The
Kevlar section will be attached to
the motor mount and the nylon
section will be attached to the nose
cone.
Wrap the end of the Kevlar shock
cord around the forward end of the
motor tube and tack in place with
CA.Makesurethecordlaysat
enough so it will not interfere with
the body tube when you slide the
motor tube inside. Apply some
epoxy to the cord to hold it in place.
Make sure the cord is secure
and will not come loose later with
ejection forces that will pull on the
shock cord. Step 5 – Launch Lug
Mark the CP point along the launch lug line you made in the previous step. Make sure
you measure the CP point from the tip of the nose cone and NOT the end of the body
tube. Apply a small amount of epoxy on the launch lug line about ¾” long on the CP
mark. Press one of the launch lugs into the epoxy and ensure that it is aligned with the
launch lug line previously drawn on the body tube. You can site down the tube and look
through the launch lug to make sure it is straight. Similarly epoxy the second launch
lugabout2”fromtheaftendofthebodytube(alignedwiththeaftendofthens).Site
down both launch lugs and make sure they are both aligned. If you have a ¼” launch
rod, you can use this to ensure that both lugs are aligned properly.
Step 4 - Conduit Assembly
Side View
End View
Trim each conduit balsa stick to 17” and carefully sand the conduits so they
form a 1/2 round conduit as shown. Also taper the fore and aft end of the
conduit as shown.
Glue each conduit to the body tube carefully aligned them to the marks you
made earlier.

IMPORTANT: always use positive motor retention to secure the motor.
Failure to use motor retention will cause the motor to be ejected instead
of the parachute making for a dangerous ballistic reentry.
IMPORTANT: always remember to check your balance point and ensure
your CG is forward of the specied CG point.
IMPORTANT: Always follow the NAR safety code and remember that
rockets are not toys and can be dangerous if not prepared and used
properly. If you are a beginner, it is a good idea to y with a club or other
group of experienced rocketeers until you have gained some experience.
IMPORTANT: In no event shall Madcow Rocketry be liable for any direct,
indirect, punitive, incidental, special consequential damages whatsoever
arising out of or connected with the use or misuse of it’s products. The
buyer assumes all risk and liability resulting from ANY use of any and
all products sold by Madcow Rocketry. Your purchase and use of any
Madcow Rocketry product constitutes your agreement to and acceptance
of these terms. If you do not agree to these terms and conditions, you
must return the unused product in resalable condition for a refund or
credit.
IMPORTANT: Please contact us via phone or email if you have any
questions about constructing or ying your model.
23016 Del Lago, Unit C
Laguna Hills, CA 92637
949.547.8847
www.madcowrocketry.com
©2014 MadCow Rocketry™
®
Step 7 – Flying Your Model
Attach the parachute to the shock cord 2/3 of the way between the nose cone and body
tube. You can also attach the chute protector to the shock cord near the parachute.
When packing your chute, wrap the chute protector around the chute with the opening in
the chute protector facing forward. Always make sure your chute is well protected as the
hot ejection motor gasses will melt the nylon chute.
Step 6 – Balancing Your Model
Assembleyourmodelandinsertthelargestmotoryouintendtoy(orsimulatethe
weight with a substitute) and ensure that the CG is at least 1 body diameter in front of
theestimatedCPpointspeciedontherstpage.TheCPpointismeasuredfromthe
tip of the nose cone. If the CG is behind the desired point, add weight inside the nose
cone by pouring lead shot into the nose cone tip and adding some epoxy. You can drill
a 1/4” hole in the base of the nose cone to make it easier to pour lead shot and epoxy
inside the nose cone.