Apogee Midge User manual

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Colorado Springs, Colorado USA
web site: www.ApogeeRockets.com
The Midge rocket is another ne product from:
Kit #05045
Midge
(A Two-Stage Payload Altitude Rocket)
P/N Description Qty
Parts List
13000 Coupler 18mm X 0.35” (Red) 2
10055 Engine Mount Tube AT-13/8.0” 1
10082 Payload Tube AT-18/5.0” 1
12350 CBD-18mm Sheet 1
12999 Coupler AC-18C (Brown NAR Payload) 1
13012 Coupler AC-13 1
13020 CR 10/13 (green) Engine Block 1
13029 CR 13/18 (blue) Centering Ring 1
13051 1/8” Launch Lug 1” Long 1
15552 Midge Fins 1/16” X 3” X 3” 1
19012 13-to-18mm Ogive Transition (VF) 1
19207 Vac Form Nose Cone VFNC-18 1
29519 100# Kevlar X 6 ft 1
29111 8” Hexagon Orange Plastic Parachute (1/pk) 1
31013 Midge Instruction Sheet A 1
31014 Midge Instruction Sheet B 1
35535 13mm 3-Fin Alignment Guide 1
47122 Clear Plastic Bag 6x14x2mil 1
Other Tools and Materials Needed
Pencil
Hobby knife
Wood glue
Super glue (thick viscosity)
Plastic packaging tape
Paint supplies (spray paint, brushes, etc.)
Wood sealer
Sandpaper (220 and 400 grit)
Wood dowel for spreading glue inside tubes
Sand (28 grams - not included)
p/n 31013
Shock Cord Anchor Pattern
The Midge is a two-stage payload altitude rocket
designed specically for NAR competitions. Use it in
single stage conguration in the A-altitude competition,
or two-stage in the “B-altitude” event (because two A-
size engines added together is equivalent to the power
of a “B” rocket motor).
The dual-diameter rocket is sized to carry the NAR
Standard Payload and an altimeter that t into an
18mm payload tube. With its custom vacuum-formed
transition section the Midge then reduces down to a
13mm motor at the bottom to decrease the weight and
lower the drag. This rocket also comes with a cardstock
n alignment guide to assure that the ns are perfectly
straight and evenly spaced around the rocket. This low-
ers the drag, and allows the rocket to y to new record-
setting altitudes.
Skill Level 3: Average Skills Needed
MIDGE
MIDGE

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Assemble The Midge Rocket
1. Remove the parts for the n alignment
xture from the cardboard sheet. Dry as-
semble the parts as shown. Make sure the
tabs on the cross pieces protrude through
the side plates. Apply a bead of wood glue
over the tabs on both sides of the tool. Set
the piece aside to allow the glue to dry.
2. Separate the tubes. Sand off the little
nubs of paper on the ends of the tubes using
medium grit sandpaper.
3. Glue one of the red paper tube cou-
plers into the base (as far as it can go) of
the nose cone using thick viscosity CyA glue
(also called super glue). Set it aside to allow
the glue to harden.
4. Taking the point of your hobby knife,
carefully drill a small hole into the base of
the shoulder on the vacuum form plastic
transition. The hole only needs to be slightly
larger than the diameter of the yellow shock
cord.
5. Glue the remaining red paper tube
coupler into the front of the plastic transition
as far as it will go using thick viscosity CyA
glue. Set it aside to allow the glue to harden.
Tip: Paint the inside of the transition black
to block sunlight from affecting the altimeter.
Why? Because the pressure sensor is often
affected by bright light.
6. This step for FireFly Altimeter - If
using the MicroPeak, skip to step 9. Mark
a pencil line on the brown payload tube 1.4
inches (35.5mm) from one end. It will be
used to push in the blue centering ring.
2
3
4
5
6
1
Glue
(both sides)
1.4 inch (3.5 cm)
For FireFly
Altimeter

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7. Place a small amount of wood glue
on the tip of a wood dowel. Smear the glue
around the inside perimeter of the white pay-
load tube, 1.25 inches (3 cm) deep on the
end of the tube with the small holes.
8. Using the brown tube from step 6,
push the blue ring into the glue from step 7.
The 1.4-inch (3.5cm) line should be even
with the end of the payload tube. Remove
the brown tube immediately and wipe out
any excess wood glue from inside the
payload tube (on both sides of the blue ring)
and off the brown tube. Allow the glue to dry.
Continue on to Step 12.
9. When using the MicroPeak altim-
eter, follow the next three steps.
Since the MicroPeak is a smaller altim-
eter, it will t into the transition of the rocket.
Therefore the payload tube can be made
shorter so the rocket weighs less and ies
higher.
Using a hobby knife, cut the payload at
the eteched line on the opposite end of the
holes. Using sandpaper and sanding block,
make sure the edge is smooth and at.
10. Place a small amount of wood glue
on the tip of a wood dowel. Smear the glue
around the inside perimeter of the tube, just
in front in the small holes.
11. Using the brown tube push the blue
ring into the glue from step 10. The blue ring
should be just in front of the small holes, so
they are not blocked. Remove the brown
tube immediately and wipe out any excess
wood glue from inside the payload tube (on
both sides of the blue ring) and off the brown
tube. Allow the glue to dry.
1.25 inch (3cm)
For FireFly
Altimeter
For FireFly
Altimeter
Brown tube
Brown tube
For MicroPeak
Altimeter Only!
For MicroPeak
Altimeter Only!
Do not block vent holes
For MicroPeak
Altimeter Only!
p/n 31014
7
8
9
10
11
1.4 inch (3.5 cm)

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12. Fine sand the balsa wood laser-cut
sheets using 200 and then 400 grit sand-
paper before removing the ns. Carefully
remove all the pieces from the sheet by free-
ing the edges with a sharp hobby knife.
For higher ights, round the edges of the
ns with sandpaper – or better yet – sand an
airfoil shape into them. Test t the ns into
the slots on the n alignment xture. If they
are too tight, you will need to sand down the
thickness slightly.
13. Sealing the surface of the balsa with
sanding sealer reduces the skin friction drag
on the rocket, allowing it to y higher. It also
improves the rocket’s appearance. Apply the
sealer with a paintbrush. When dry, sand it
with 400 grit sandpaper. Repeat the proce-
dure until the balsa grain is lled and the ns
look and feel smooth.
14. Slide the n alignment xture onto the
long body tube over the end that is etched
with the n lines. Test t the smaller set of
ns into the xture. Position the trailing edge
of the ns on the tick-marks that are etched
onto the n lines. When you know how the
ns are attached, you can remove them from
the n alignment xture and apply wood glue
to the root edge and then put them back into
the n alignment xture. Allow the glue time
to dry before removing the n xture.
15. Repeat the process of attaching the
ns, but this time use the larger ns and at-
tach them to the short booster stage tube.
OPTIONAL: For competition ights, it is
recommended that you launch the rocket
from a piston launcher or from a launch
tower. But if you do not have one, you’ll
need to use a standard launch rod. In that
case, install the launch lug as follows.
16. Glue the balsa wood standoff to the
front end of the body tube in the position
marked on the tube. When the glue is dry,
glue the launch lug to the stand-off using
wood glue. Make sure the lug is parallel to
the length of body tube.
17. Add wood glue llets to the ns and
the launch lug (if added). Lay the rocket
horizontally to let the glue dry.
12
17
16
15
14
13
Smaller
ns
Sustainer (upper stage)
Larger ns used
in booster stage
Fin location
line
Fin location
line

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18. OPTIONAL: Glue the green engine
block into the long sustainer tube, 1-1/4
inches (3.2cm) deep. To save weight, you
can leave out this piece.
19. Cut out the shock cord anchor from
the front of instruction sheet. Spread glue
on one side. Take the free end of the shock
cord and lay it diagonally across the paper.
Fold it twice on the marked lines, and then
curl it slightly so it will t into the long tube
with the ns.
20. Glue the shock cord mount into the
front of the long tube with the ns on it.
Make sure it is deep enough to allow the
shoulder of the payload section to be in-
serted into the tube.
21. Thread the free end of the yellow
shock cord through the hole in the base of
the transition. Tie a loop in the front end.
This will give you a place to tie the altimeter
to the rocket in case the model separates
in ight. Tie a big enough knot about 1.5
inches (3.8 cm) from the tip of the loop in
the cord so it can’t be pulled out through the
hole. Pull the cord so the knot is at the base
of the transition. Using thick CyA adhesive,
glue the knot inside the base of the plastic
transition.
22. Tie a loop knot into the shock cord
as close to the base of the transition as you
can. This will be the loop used to attach the
parachute.
23. Assemble the NAR Payload by gluing
a cardstock bulkhead disk ush with the end
of the brown tube using wood glue. Allow
the glue to dry. Fill the tube with ne sand
(not included) so the entire payload weighs
28.0 grams. Remember to include the mass
of the second bulkhead when weighing it.
Shake the tube to settle the sand. Then glue
the second disk on the open end and allow
it to dry.
20
21
22
23
19
18
1-1/4” (3.2cm)
1.0” (2.5cm) minimum
Approx. 1.5” (3.8cm)
Pull tight

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24. Place one reinforcement ring on each
of the corners of the parachute canopy.
Take a sharp pencil or knife and poke a hole
through the plastic in the center of each ring.
25. Cut the shroud lines to make a total
of three lines of equal length. Then pull each
parachute line end through a parachute re-
inforcement ring and tie using two overhand
knots. Repeat for all the corners as shown.
26. Holding the parachute at the center of
its top, pull the lines together to even up the
ends. Thread the three looped lines through
the loop in the shock cord. Next, take the top
of the parachute and pull it through all three
string loops at the same time. Finally, pull on
the strings to tighten the knot. This securely
attaches the parachute to the rocket.
27. Fold the parachute and insert it into
the rocket along with the shock cord.
28.Temporarily assemble the rocket. You
can use the red tube coupler to join the two
stages together. Roll a piece of paper and
insert it into the back of the rocket to hold
the model while you paint it. We recommend
a uorescent color like orange, pink or yel-
low to make it easier to nd the rocket after
touchdown. Allow the paint time to dry.
Congratulations! Your Midge rocket is
now complete.
Launch Supplies Needed
To launch your rocket you will need the
following supplies:
• A model rocket launching system
• Flame resistant recovery wadding
• Recommended Rocket Engines:
See the motor matrix to the right.
red coupler
Midge Rocket Recommended Motors
Engine Manufacturer Altitude (ft) Altitude (m)
A10-3T Estes 259 79
A10-0T / A3-4T Estes 671 204
A10-0T / A10-3T Estes 637 194
24
25
26
27
28

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Tape
Motor Retention for when the
sustainer is own with the
booster stage
Altimeter
NAR Payload
String - tie altimeter
to transition
Tape
Do not cover vent holes
Rocket Preight
A. Crumple and insert one-half of a sheet
of recovery wadding into the body tube.
B. Fold that parachute and insert it into
the tube with the shock cord. Then insert the
plastic transition section onto the tube.
C. Tie a string from the loop inside the
transition to the altimeter for extra security in
case the rocket comes down in two separate
pieces. Turn on the altimeter and insert it
into the rear of the payload tube (closest to
the vent holes), and then insert the shoulder
of the transition too. Place the NAR payload
into the forward end of the payload bay, and
then insert the nose on top.
D. Wrap tape around the perimeter over
the two ends of the payload tube as shown.
Make sure not to cover the vent holes for the
altimeter.
E. If ying the sustainer alone as a single
stage, it is preferable to hold the engine in
the tube by wrapping tape about the portion
of the motor that extends out the rear of the
tube as shown.
F. If you’re ying the Midge as a two-
stage rocket, the motor in the top stage is
friction tted into the tube.
G. For the booster stage the motor is
inserted so the motor extends out the back
3/8” (0.9 cm) and then held in place by wrap-
ping tape around the perimeter of the motor
and the tube.
Motor Retention for when
the sustainer is own alone
(without the booster stage)
Tape
Booster Stage
Tape
F
G
A&B
C
D
E
3/8” (0.9 cm)

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H. The two stages are joined together by
inserting the upper stage motor (the portion
that sticks out) into the front of the booster
stage.
I. Insert and secure the engine igniter as
directed on the package the engines came
with.
Countdown and Launch Procedure
Fly your rocket on a large eld that isn’t
near any power lines, trees, or low ying
aircraft. The larger the eld, the greater
your chances of recovering your rocket. The
launch area around the pad must be free of
dry weeds and brown grass. Launch only
during calm weather with very little or no
wind and good visibility.
10. Remove the safety key from the
launch controller.
9. Slide the launch lugs over the launch
rod to place the rocket on the pad. The
rocket should slide freely over the rod.
8. Attach the micro-clips to the igniter.
The clips must not touch each other or the
metal blast deector.
7. Stand back from your rocket as far as
the launch wire allows (at least 5 meters - 15
feet).
6. Insert the safety key to arm the launch
system. The light (or buzzer) on the control-
ler should come on.
Give a loud countdown 5 ... 4 ... 3 ... 2 ...
1 ... LAUNCH!
Push and hold the the button until the en-
gine ignites. Then remove the safety key and
place the safety cap on the launch rod.
*National Association of Rocketry
**Kevlar® is a brand name of E.I. DuPont for their selection of aramid bers. Only DuPont makes Kevlar®
Always follow the NAR* Model Rocket Safety Code when launching
model rockets.
Misre Procedure
Occasionally the igniter will burn, but the motor will fail to ignite. If this
happens, the cause is that the pyrogen on the igniter was not in contact
with the engines propellant. When an ignition failure occurs, remove the
safety key from the launch controller and wait 60 seconds before ap-
proaching the rocket. Remove the old igniter from the engine and install
a new one. Make sure that the igniter is insert fully into the engine and
touches the propellant. Secure the igniter as directed on the engine pack-
age and repeat the countdown and launch procedure.
H