Molt models parkflyer p-38 lighting Instruction Manual

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Pa ar rk kf fl ly ye er r
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P- -3 38 8 L Li ig gh ht tn ni in ng g

Molt Models P-38 Building Instructions Rev A
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Molt Models Background Design Philosophy
When I was first introduced to this hobby eighteen years ago I saw my first WWII
warbird and I was hooked. Several years later when I began building radio controlled
model airplanes on my own, I learned that along with the intriguing warbird looks
came a plane that was usually difficult to fly. After a few disheartening attempts with
some larger glow powered warbirds I thought about how great it would be if I could
design a spirited yet forgiving warbird that could be flown in a space the size of a
soccer field. At that time the level of technology was not advanced enough to make
this a reality, but the developments in the last few years have made it possible and
economical.
The Molt Models design philosophy is comprised of methods that enhance scale
appearance and all around flight performance. The first thing you’ll notice about a
Molt Models kit is that the majority of wood parts, illustrations and plans are CAD
based. These items are derived from the same 3D modeling environment that the
plane was designed in. My goal is to cut down on wordy instructions and use a more
visual approach that will get you from kit to airborne in as little time as possible.
Molt Models Parkflyer P-38 Lightning
Thank you for purchasing the Molt Models Parkflyer P-38 Lightning. This kit represents a
true first in parkflyer warbirds in that it possesses characteristics that make it both
enjoyable to build and more importantly, fly. I sincerely hope that you enjoy your new
Molt Models kit. Please visit us at www.moltmodels.com for updates and information
on future kits.
Manual Revisions
Rev A - Figure 18 (wing tip measurement) 3-5/16” was 2-3/16” in “Wing Halves Joined” section

Molt Models P-38 Building Instructions Rev A
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Molt Models Parkflyer P-38 Lightning Specifications and Kit Requirements
The P-38 Lightning is a fully functional aileron, rudder, elevator, and throttle controlled
aircraft (4 channel). You may build the P-38 Lightning to fly with aileron, elevator, and
throttle only by gluing the rudders to the vertical stabilizers. If you decide to do this I
would recommend that you leave the landing gear off as take off and landing on a
hard surface will be difficult without a rudder. I also recommend leaving the landing
gear off if you intend to fly on grass only. If you fly on a nice hard surface, the P-38
Lightning with all functions and landing gear is quite impressive. On the other hand I
definitely do not recommend you attempt to fly the P-38 Lightning as a rudder,
elevator, and throttle only model.
P-38 Lightning Specifications
Length: 26 in
Wing Span: 38 in
Wing Area: 216 in2
Flying Weight: 10.0 ~ 12.0 oz
Wing Loading: 6.67 ~ 8.00 oz/ft2
Power System: GWS S1 IPS
Functions: Aileron, Elevator, Rudder, & Throttle
Battery Pack: 7.4V, 1200mAh or larger Lithium Polymer
Parts you will need to complete the P-38
Lightning kit:
• (2) GWS IPS (“S1” gearing) and
manufacturer recommend propellers
• (1) 4 channel receiver
• (1) 10A Electronic Speed Control
• (3) Servos (Hitec HS-55 or GWS Pico/Naro)
(4 Channel)
• (2) 12” servo extensions
• (2) Female JST connectors
• (1) Male JST connector
• (1) Red wire, 20” long
• (1) Black wire, 20” long
• (1) Roll of Nelson Lite Film AKA Solite
covering
Supplies and tools you will need to complete
the P-38 Lightning kit:
• Hobby knife and blades
• Stickpins
• Pliers
• 90-degree triangle
• Ruler
• Covering iron
• Fine tip ink pen
• Fine/medium sand paper
• 5-minute epoxy
• Thin CA glue and fine extension tip
• Wood glue
• Wax paper or plan protection plastic
• 3/4" transparent tape
• Masking tape

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General Model Building Tips and Orientation
First and foremost, this kit is NOT for the first time wood kit builder. Having said that, if
you study the plans and instructions and get help from an experienced builder it’s
quite possible to build a nice flying model from this kit. Lastly, keep in mind that this kit
is a reasonably scale model of a real WWII airplane and consists of complex shapes. It
WILL NOT build as easily as the typical box, slab sided laser cut kits that you may have
built.
Please be sure to study the plan sheets and read through the following instructions
before attempting to build your P-38 Lightning. Having a good idea of what to expect
as you progress will cut down on mistakes and allow you to better organize your
project. Checkboxes have been provided in front of each step that allows you to
easily keep track of your work.
Begin each building section by taping the corresponding plan sheet to your building
surface; masking tape works great for this. Next cover the area of the plans you will be
building over with plan protection plastic or wax paper. This will keep your plans from
sticking to your model.
It is often necessary to pin parts of the model over the plan sheet as you progress
through the build. In conjunction, it will be necessary to have a building
surface/board that allow pins to stick into it with ease. I recommend using the smallest
diameter “stick pins” you can find as larger diameter pins can split the wood.
Appropriate sized pins are available in the craft and sewing section of most major
discount stores.
Thin CA glue is suitable for almost all the build sections of this model. If another type of
glue is necessary for a certain build section it will be recommended in that segment.
Standing behind the plane orients the left and right side of the model. The plans and
building instructions refer to areas of the model in this manner.

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Build Section #1 – Boom Construction
The booms of the P-38 are constructed in two halves and then glued together to form a single boom.
The boom building section of the plans refer to “Right Boom Components” and “Left Boom
Components”. In addition, both the Right and Left Boom Components consist of an “Outside Half” and
an “Inside Half”. If you take care to build only one boom half from each of the four boom halves shown
on the plans you will not have to worry about building incorrect boom parts. To avoid making this
mistake, mark off each boom half shown on the plans as “completed” when you finish them.
Outside Boom Half
 Pin boom keels K1, K4, and K6 over one of the outside boom halves shown on the plans and glue
adjacent edges.
 Glue the boom formers O1, O2, O4, O7, O8, O9, and O10 to K1, K4, and K6 making sure they are
perpendicular to the building surface. Be sure to orient each of the boom formers so that the
notches that accept K8 are in a line as you site down the boom.
 Install, but DO NOT glue the boom formers O3, O5, and O6.
 Glue K8 into the notches of each of the boom formers O1, O2, O3, O4, O5, O6, and O7. Note that
K8 orients O3, O5, and O6 at proper angles that interface the wing. Finish by gluing O3, O5, and O6
to K1,K4, and K6.
Figure 1

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 Glue B11 and B12 into the notches of K1, K6, and O10.
 Glue pushrod exit P1 to B11 and O10.
Figure 2
 Glue 3/32” SQ. Balsa Stringers to the boom formers as shown in Figure 3 and the plans. Figure 3
illustrates important areas of the boom where stringers end.
 At this point the Outside Boom Half is complete and can be unpinned from the building board. Do
not be concerned if the boom half is a bit warped when it is removed from the building board, this
will be corrected when the boom halves are glued together.
Figure 3

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Inside Boom Half
 Pin boom keels K2, K5, and K7 over one of the Inside Boom Halves shown on the plans and glue
adjacent edges.
 Glue the boom formers I1, I2, I4, I7, I8, I9, and I10 to K2, K5, and K7 making sure they are
perpendicular to the building surface. Be sure to orient each of the boom formers so that the
notches that accept K9 are in a line as you site down the boom.
 Install, but DO NOT glue the boom formers I3, I5, and I6.
 Glue K9 into the notches of each of the boom formers I1, I2, I3, I4, I5, I6, and I7. Note that K9 orients
I3, I5, and I6 at proper angles that interface the wing. Finish by gluing I3, I5, and I6 to K2, K5, and K7.
Figure 4
 Glue B11 and B12 into the notches of K2, K7, and I10.
 Glue pushrod exit P2 to B11 and O10.
 Glue K3 to K2, I4, and I5. K3 supports the landing gear.
Figure 5

Molt Models P-38 Building Instructions Rev A
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 Glue 3/32” SQ. Balsa Stringers to the boom formers as shown in Figure 6 and the plans. Figure 6
illustrates important areas of the boom where stringers end.
 At this point the Inside Boom Half is complete and can be unpinned from the building board. Do
not be concerned if the boom half is a bit warped when it is removed from the building board, this
will be corrected when the boom halves are glued together.
Figure 6

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Boom Halves Joined
 Glue the outside boom and inside boom halves together. Take care to insure the mating formers
I3/O3, I4/O4, I5/O5, I6/O6 are aligned and flush with each other. Be sure to glue each of the
mating formers and keels. A longer, more precise tip on your CA glue bottle can help here.
Figure 7

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 Find the 3/16” x 5/16” IPS mounting stick in the kit and cut it to the length shown in Figure 8.
 Using a pencil, place marks on the mounting stick as shown in Figure 8. Make sure the GWS IPS
gearbox will slide over the mounting stick as far as it will go before gluing it to the boom. The back
of the gearbox should end up very close to the line drawn at 15/16”.
 Remove the GWS IPS gearbox from the mounting stick and slide the mounting stick into the
rectangular holes in I2/O2 and I3/O3. The mounting stick should slide all the way in until the line
drawn at 1-3/8” reaches the front of I2/O2. Glue the mounting stick to I2/O2 and I3/O3, be sure to
flood the joints with thin CA to assure a good bond.
 Glue servo mount M1 to K8, K9, and I3/O3 as shown in Figure 8. Sand the boom to eliminate uneven
rough wood surfaces and excess dried glue. At this point the boom is complete.
Figure 8
At this point, one of the booms is complete. Build the other boom by starting at the
beginning of the Boom Construction section of this manual. Note that this boom will
be a mirror image of the previously constructed boom.

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Boom Covers
 Pin C8 and C9 over the “Left Boom Cover” shown on the plans. Make sure C8 and C9 are
perpendicular to the building surface.
 Glue C1, C2, C3, C4, and C5 to C8 and C9 as illustrated in Figure 9.
 Glue the top 3/32” SQ. Balsa Stringer, C6 and C7 to C1 through C5. Be sure to dry fit C6 and C7
before you begin gluing by pinning them to C1 through C5, starting at C5 and working your way
forward. When you are satisfied with the fit of C6 and C7 glue them to C1 through C5. There will be
some excess C6 and C7 material that protrudes out from C1, trim this off flush with C1 when the glue
is dry.
 Glue the remaining 3/32” SQ. Balsa Stringers to C1 through C5, C6 and C7. The stringer that
interfaces with C7 will have to be cut at an angle to have a good fit.
 Unpin the boom cover and finish cutting the small sections of balsa that retain the airfoil shaped
bottom of C8 and C9.
 Build the “Right Boom Cover” shown on the plans in the same manner used to construct the “Left
Boom Cover”. Sand the boom covers to eliminate uneven rough wood surfaces and excess dried
glue. At this point the boom covers are complete.
Figure 9

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Boom Cowlings
 Glue L1, L2, L3, and L4 together as shown in Figure 10 with wood glue.
 Sand the lamination of L1, L2, L3, and L4 to the final shape shown in Figure 10. The engraved dashed
line on L4 is a guide to aid in the sanding process.
 Build an identical boom cowling from the additional set of L1, L2, L3, and L4 formers. At this point the
boom cowlings are complete.
Figure 10

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Build Section #2 – Fuselage Construction
The fuselage of the P-38 is constructed in two halves and then glued together to form the complete
fuselage. The fuselage building section of the plans refer to “Right Fuselage Half” and “Left Fuselage
Half”. Fuselage Halves
 Pin fuselage keels F11, F12, and nose gear former G1 over the “Left Fuselage Half” (“Right Fuselage
Half” when working through this section for the second time) shown on the plans and glue adjacent
edges.
 Glue fuselage formers F1, F2, F3, F4, F6, F7, F8, F9, and F10 to F11, F12, and G1 making sure they are
perpendicular to the building surface. Be sure to orient each of the fuselage formers so that the
notches that accept F13 are in a line as you site down the fuselage.
 Install, but DO NOT glue the fuse former F5.
 Glue F13 into the notches of each of the fuselage formers F1 through F10. Note that F13 orients F5 at
the proper angle to interface the wing. Finish by gluing F5 to F11, F12, and F13.
 Glue servo mount M2 to F6, and F7 as shown in Figure 11. Note M2 is NOT installed in the “Right
Fuselage Half”.
 Install the rudder and steering servo with the mounting screws included with the servo. Note the
orientation shown in Figure 11. The servo arm should be trimmed/modified to an “L” shape; this
matches the arm shown in Figure 11.
Figure 11

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 Glue G2 and G3 to G1, F3, F4, and F11. When G2 and G3 are installed there should be a 1/16” gap
between them, which receives the nose gear assembly. Be sure to fit the 1/16” nose gear wire into
the gap so it that rotates without excessive friction.
 Glue N1, N2, N3, and N4 to F1 and each other with wood glue.
 Construct the nose gear as shown in “Nose Gear Bending Template and Assembly” section of the
plans. Insert the nose gear assembly into the 1/16” gap between G2 and G3. The plastic 1/8" O.D.
plastic tubing sections will ride on the top and bottom of G1, G2, and G3.
 Glue G4 to G2, G3, F3, and F4 to encapsulate the nose gear assembly. Be careful not to get glue on
any part of the nose gear assembly. The nose gear is now a permanent part of the left fuselage half
and should rotate freely. Note the nose gear assembly will be tilted at an angle while it is pinned to
the building surface.
 Drill a 1/16” DIA. hole through the center of the 3/16” SQ. X 1/4" LG. Hardwood block and glue the
plywood nose gear arm to it as shown in Figure 12.
 Construct the Nose Gear Actuation Link that connects the nose gear assembly to the rudder and
steering servo as shown in “Nose Gear Actuation Link” section of the plans.
 Insert the Nose Gear Actuation Link into the hole and slot of fuselage formers F3 and F4.
 Slide the Hardwood block/plywood nose gear Arm assembly onto the “Z” Bend of the Nose Gear
Actuation Link as shown in Figure 12. Next, slide the Hardwood block/plywood Nose Gear Arm
assembly onto the nose gear assembly so that it lines up flush with the end of the 1/16” wire. This is
illustrated in Figure 12 and should be glued with 5-minute epoxy to ensure a strong bond. Once the
stringers are installed it will be difficult to gain access to this area of the fuselage again.
Figure 12

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 Glue 3/32” SQ. Balsa Stringers to the fuselage formers as shown in Figure 13 and the plans. Figure 13
illustrates important areas of the fuselage where stringers end.
 At this point the left fuselage half is complete and can be unpinned from the building board. Do
not be concerned if the fuselage half is a bit warped when it is removed from the building board,
this will be corrected when the boom halves are glued together.
 Build the right fuselage half by starting at the beginning of the Fuselage Halves section of this
manual and working from the “Right Fuselage Half” section of the plans. Note that the right
fuselage half will not include any of the provisions to mount the nose gear or rudder and steering
servo. Only the left fuselage half contains structure and hardware for the nose gear.
Figure 13

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Fuselage Halves Joined
 Glue the left fuselage and right fuselages halves together. Take care to insure the mating formers F1
through F10 are aligned and flush with each other. Be sure to glue each of the mating formers and
keels. A longer, more precise tip on your CA glue bottle can help here.
 Glue T1 through T10 to F13s, F10, and each other with wood glue.
 Install the nose gear wheel. The nose gear wheel is held on with short section of 1/8” O.D. plastic
tubing cut to 1/8” LG. The plastic tubing is attached with thin CA glue to the nose gear wire, be
careful not to get any glue on the wheel. This is illustrated in Figure 14. (Note, the Du-bro wheels
may have to be drilled out to fit the nose gear wire)
 Install the Micro Connector to the servo arm in the location illustrated in Figure 14. Slide the Nose
Gear Actuation Link into the Micro Connector, center the nose gear and tighten the Micro
Connector screw to retain the Nose Gear Actuation Link.
 Sand the nose and tail of the fuselage smooth to blend into the shape of the fuselage. Also, sand
the fuselage to eliminate uneven rough wood surfaces and excess dried glue. At this point the
fuselage is complete.
Figure 14

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Build Section #3 – Wing Construction
The wing of the P-38 is constructed in two halves and then glued together to form the complete wing.
Wing Halves
 Create the laminated spars, S1 and S2 by gluing two S1’s and two S2’s together by using the “Spar
Lamination” section shown on the plans. Laminate these spars with wood glue or epoxy and pin
over the plans to make sure they remain straight and true.
 Pin laminated S2, 3/32” SQ. Balsa, W11, and E1 over one of the wing halves shown on the plans and
glue adjacent edges.
 Glue R2 through R15 to laminated S2, 3/32” SQ. Balsa, W11, and E1 making sure they are
perpendicular to the building surface. Note R2 has to be scored on the etched line with your
modeling knife to fit the shape shown on the plans. Flood the scored line of R2 with CA glue after it
is pinned to the shape shown on the plans.
 Glue R1 to the laminated S2, 3/32” SQ. Balsa, and E1 making sure it is tilted to the angle created with
the use of the “Rib R1 angle gauge” shown on the plans and illustrated in Figure 15.
 Glue W12 and W13 to W11 and R15.
Figure 15

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 Glue laminated S1, 3/32” SQ. Balsa, and LE to R1 through R15 and W11 where applicable.
 Glue A9 to R13 and the bottom 3/32” SQ. Balsa.
Figure 16

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 Glue the two 3/32” SQ. Balsa to R1 through R15.
 Glue A8 to the two 3/32” SQ. Balsa, R15, and R11.
 Glue shear webs W1 through W10 to laminated Spars S1, S2, and adjacent ribs. Note that the grain
of these shear webs is always perpendicular to the building surface. The orientation of each shear
web can be seen in Figure 17. Ailerons
 Pin E2 over one of the ailerons shown on plans.
 Glue and pin A1 through A5 to E2 making sure they are perpendicular to the building surface.
 Glue A7 to A1 through A5.
 Glue A6 to E2 and E7. The gap between A6 and A3 is intentional and allows a place for the aileron
control horns to be glued.
Figure 17
 Build the other wing half and aileron by starting at the beginning of the Wing Halves section of this
manual and working from the plans.

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Wing Halves Joined
 With one wing half fixed flat to the building surface, glue on the other wing half with the tip elevated
to the dimension shown in Figure 18. Join the two wing halves with Epoxy.
 Sand the leading edge of the wing blending it into the shape of the wing/airfoil. Also, sand the wing
to eliminate uneven rough wood surfaces and excess dried glue.
Figure 18
Build Section #4 – Horizontal/Vertical Stabilizer, Elevator, and Rudder Construction
 Build the horizontal stabilizer, elevator, vertical stabilizers, and rudders per the “Tail Components”
section of the plans.
Build Section #5 – Control Installation
To maintain scale functionality, manage weight, and minimize the number of servos, the Molt Models
P-38 makes use of a creative control system. The rudder servo is mounted in the fuselage and is
required to operate the nose gear (if installed) as well as both rudders. The elevator servo is mounted in
the left boom, and the aileron servo is mounted in the right boom.
Each component containing a hole with an engraved letter next to it designates a place where a
control tube will be routed through. The letter “r” designates a hole where a rudder control tube will
pass through, and similarly, “a” for aileron, and “e” for elevator. In most areas where a control tube
passes through you should glue the tubing to the component. However, there are areas where the
tubing SHOULD NOT be glued to a component and those areas are marked with an exclamation point
enclosed in a triangle. See Figure 19.