Twisted Hobbys Crack Yak-55 lite series User manual

Rev: 2012.11.04.v004a 1
32” Crack Yak-55
By RC Factory
RC FactoryRC Factory
RC Factory
Specifications
Wing span – 32” / Length – 31”
AUW 160-175g with Landing Gear)
50 - 70w outrunner motor 19g – 24g)
6 - 12 amp ESC / 2s 360 – 450mAh battery
4 ch radio / 2x 4g servos / 1x 9g servo
8x4.3 prop
USA Distributor
Twisted Hobbys
www.twistedhobbys.com

Rev: 2012.11.04.v004a 2
TABLE OF CONTENTS
Page
WARNING INFORMATION...................................................................................................................................................3
SHIPPING DAMAGE...............................................................................................................................................................3
OUR MISSION ..........................................................................................................................................................................3
SAFETY NOTES .......................................................................................................................................................................4
IMPORTANT: PRIOR TO ANY ASSEMBLY ..............................................................................................................4
KIT CONTENTS .......................................................................................................................................................................5
OPTIONAL PARTS..................................................................................................................................................................6
TOOLS & ADHESIVES NEEDED..........................................................................................................................................7
THE BUILD ...............................................................................................................................................................................8
CENTER OF GRAVITY ........................................................................................................................................................48
CONTROL THROWS ............................................................................................................................................................48
3D Flight ..........................................................................................................................................................................48
Sport.................................................................................................................................................................................48
PRE-FLIGHT & TESTING ...................................................................................................................................................49
PREFLIGHT CHECKS ...............................................................................................................................................................49
Motor................................................................................................................................................................................49
Flight Controls .................................................................................................................................................................49
Batteries ...........................................................................................................................................................................49
Radio ................................................................................................................................................................................49
Range Check.....................................................................................................................................................................49
FLIGHT TESTING ....................................................................................................................................................................49
STORAGE ...............................................................................................................................................................................49
NOTES & S/U SHEET ............................................................................................................................................................50
TIPS AND TRICKS ................................................................................................................................................................51

Rev: 2012.11.04.v004a 3
TWISTED HOBBYS
Website: www.twistedhobbys.com – email: [e-mail]
Thank you for your purchasing a Twisted Hobbys’ model. Please read through the entire manual before
beginning to build this model. If you have any questions please contact us at the above indicated email address.
WARNING INFORMATION
WARNING INFORMATIONWARNING INFORMATION
WARNING INFORMATION
This R C Aircraft is not a toy! Read and understand the entire manual before assembly. If misused, it can
cause serious bodily harm and property damage. Fly only in open areas, and AMA ( Academy of Model
Aeronautics
) approved flying sites. Do not over look the warnings and instructions enclosed or those provided
by other manufactures’ products. If you are not an experienced pilot and airplane modeler you must use the
help of an experienced pilot or an authorized flight instructor for the building and flying of this model aircraft.
These instructions are suggestions only on how to assemble this model. There are other ways and methods to
do so. Twisted Hobbys has no control over the final assembly, the materials and accessories used when
assembling this kit, or the manner in which the assembled model, installed radio gear and electronic parts are
used and maintained. Thus, no liability is assumed or accepted for any damage resulting from the use of the
assembled model aircraft or from this instruction manual including but not limited to direct, indirect,
incidental, special, and consequential damages. By the act of using this user-assembled product, the user
accepts all resulting liability. In no event shall Twisted Hobbys’ liability exceed the original purchase price of
the kit.
SHIPPING DAMAGE
SHIPPING DAMAGESHIPPING DAMAGE
SHIPPING DAMAGE
Twisted Hobbys checks each plane before shipping to ensure that each kit is in fine condition. We have no
bearing on the condition of any component parts damaged by use, modification, or assembly of the model.
Inspect the components of this kit upon receipt. If you find any parts damaged or missing, contact Twisted
Hobbys immediately. We will not accept the return or replacement of parts on which assembly work has already
begun. Twisted Hobbys reserves the right to change this warranty at anytime without notice.
OUR
OUR OUR
OUR MISSION
MISSIONMISSION
MISSION
To provide the best products and service to our customers at the lowest prices possible.
We take great pride in our company, our commitment to customer service and in the
products we sell. Our online store is designed to provide you with a safe and secure
environment to browse our product catalog.
Thank you for shopping with Twisted Hobbys!
Thank you for shopping with Twisted Hobbys!Thank you for shopping with Twisted Hobbys!
Thank you for shopping with Twisted Hobbys!

Rev: 2012.11.04.v004a 4
SAFETY NOTES
SAFETY NOTESSAFETY NOTES
SAFETY NOTES
Before assembling and flying this model, read carefully any
instructions and warnings of other manufacturers for all the
products you installed or used on your model, especially radio
equipment and power source.
Check thoroughly before ever flight that the airplanes’
components are in good shape and functioning properly. If you
find a fault do not fly the model until you have corrected the
problem.
Radio interference caused by unknown sources can occur at any
time without notice. In such a case, your model will be
uncontrollable and completely unpredictable. Make sure to
perform a range check before every flight. If you detect a control
problem or interference during a flight, immediately land the
model to prevent a potential accident.
Youngsters should only be allowed to assemble and fly these
models under the instruction and supervision of an experienced
adult.
Do not operate this model in a confined area.
Do not stand in line with, or in front of a spinning propeller and
never touch it with any object.
IMPORTANT: PRIOR TO ANY ASSEMBLY
Please Note: after removing kit from shipping box, lay
each piece flat on a hard surface, this will allow the
airframe to straighten out if lightly bent from
shipping. Do not worry since EPP is very pliable and
can be bent back if out of shape.

Rev: 2012.11.04.v004a 5
kit contents
kit contentskit contents
kit contents
R C F a c t o r y 3 2 ” C r a c k Y a k - 5 5 , l i t e
standard parts list: hardware packet:
2x – wing half
4x – side force generator
1x – fuselage (3 parts)
1x – canopy
2x – fuselage truss
1x – elevator (1 parts)
1x – rudder (1 parts)
1x – 3mm dia x 700mm wing spar
1x – 3mm dia x 300mm wing spar
2x – 1mm dia x 500mm control rod
2x – 1mm x 3mm x 200mm LG strut
2x – 1.5mm dia x 170mm push rod
1x – motor mount, fiberglass
2x – 1.5mm dia landing gear axle
2x – wheels
1x – wood horn accessory kit
4x – heat shrink tubing pieces
4x – z-bend wires
4x – adjustable connectors
2x – streamlined wheel pants

Rev: 2012.11.04.v004a 6
OPTIONAL PARTS
OPTIONAL PARTSOPTIONAL PARTS
OPTIONAL PARTS
Power Combo Kit
(Matched by Twisted Hobbys)
includes:
1x
1x1x
1x – 50-70w 19-24g Outrunner Motor
1x
1x1x
1x – ESC 12A Twisted Hobbys’ Series
2
22
2x
xx
x – 4.5g digital servos
1x
1x1x
1x – 9.0g Servo
1x
1x1x
1x – prop 8x4.3
Micro
MicroMicro
Micro Receiver
Receiver Receiver
Receiver
Max Recommended Weight: 2.9g
Minimum of 4 channels required
Perfect choice for building and repairing your
Twisted Hobbys EPP planes! This is the only
adhesive you will ever need. Welder virtually bonds
anything to anything! Clear, heavy-duty, flexible
and water-proof when dry. Use indoors or out. (1) 1
oz tube
CA and Kicker
Various thickness CA glues and
Activator available from Twisted
Hobbys’
Carbon Fiber 32” Upgrade Horn
Kit for “Lite Series” Models
2x
2x2x
2x - Aileron Control Surface Arms
2x
2x2x
2x - Rudder Elevator Control Surface Arms
1x
1x1x
1x - Aileron Diff Servo Arm
12x
12x12x
12x - Rod guides
1x
1x1x
1x - Landing Gear Frame Brace
2x
2x2x
2x - Landing Gear Wheel Pants Guides
2x
2x2x
2x - Landing Gear Axle Angle Brace
4x
4x4x
4x - Landing Gear Washers
4x
4x4x
4x - Wing Spar Braces
Note: many of these “optional parts” shown or
similar items, may be available from the
Twisted Hobbys’ web store.

Rev: 2012.11.04.v004a 7
Tools
Tools Tools
Tools &
&&
& Adhesi es Needed
Adhesi es Needed Adhesi es Needed
Adhesi es Needed
•Tape Measure and
Tape Measure and Tape Measure and
Tape Measure and Ruler
RulerRuler
Ruler
•Lighter
LighterLighter
Lighter
•Small drill bits
Small drill bitsSmall drill bits
Small drill bits
•Welders Glue
Welders GlueWelders Glue
Welders Glue
•Hobby Knife w new Blad
Hobby Knife w new BladHobby Knife w new Blad
Hobby Knife w new Blade
ee
e
•Needle Nose Pliers
Needle Nose PliersNeedle Nose Pliers
Needle Nose Pliers
•Wire Cutters
Wire CuttersWire Cutters
Wire Cutters
•Low Temp Hot Glue Gun
Low Temp Hot Glue GunLow Temp Hot Glue Gun
Low Temp Hot Glue Gun
•Course Sand Paper
Course Sand PaperCourse Sand Paper
Course Sand Paper
•Scissors
ScissorsScissors
Scissors
•S
SS
Small Phillips Screw Driver
mall Phillips Screw Drivermall Phillips Screw Driver
mall Phillips Screw Driver
•CA
CACA
CA and Activator
and Activator and Activator
and Activator
•Approx 18” string thread
Approx 18” string threadApprox 18” string thread
Approx 18” string thread

Rev: 2012.11.04.v004a 8
THE BUILD
THE BUILDTHE BUILD
THE BUILD
CONSTRUCTION METHODS:
Building surface should be at least 2ft x 4ft and flat. Weights or some small heavy objects will be
handy for holding things in place during the time glue is setting.
Two types of glue are used for the build, Welders glue is use for most areas and CA for the horns
and guides. When using the Welders glue, apply
When using the Welders glue, apply When using the Welders glue, apply
When using the Welders glue, apply a thin film to each surface
a thin film to each surfacea thin film to each surface
a thin film to each surface, allow to sit for
, allow to sit for , allow to sit for
, allow to sit for
approx
approx approx
approx five
fivefive
five minute
minute minute
minutes
ss
s and then assemble
and then assemble and then assemble
and then assemble.
..
. Note that this method will create a nearly instant bond,
so locate carefully when bringing the two pieces together. If alignment is necessary while gluing
the two pieces together, do not allow the glue to tack up, simple apply and join immediately, you
will have several minutes to locate the two parts before the glue sets up. In most cases the parts
being glued can be handled with care in 30 minutes, full cure is approx 24 hours.
Carbon parts should be sanded and wiped clean prior to gluing. Take necessary precautions to
avoid breathing the carbon dust.
Remove wing spar ribs that have the
oval holes from the wood kit. These are
for the inner spar slot where the spar is
two rods thick.
The center section, to the right in this
photo, is where the oval ribs and
double spar go.

Rev: 2012.11.04.v004a 9
Remove the little tabs of foam that are
in the SFG slots with a sharp knife
Glue the wings to the fuselage with
Welders. Notice how the tabs on each
wing prevent you from putting the
wings on upside down.
NOTE: USE GLUE SPARINGLY
AND WIPE OFF OR REMOVE ANY
EXCESS. TOO MUCH GLUE WILL
INCREASE THE A.U.W. AND
AFFECT THE MODEL’S FLYING
CHARACTERISTICS.
This is how the spar assembly goes
together. Short rod in the center first
followed by the longer rod over the top
of it.

Rev: 2012.11.04.v004a 10
Welders will work it’s way through the
top of the wing. Use some clear
packing tape on the bench to keep it
from sticking. Wax paper or Parchment
paper could also be used.
Install the rods thru the wood ribs as
shown. Note that the shorter one is on
the bottom.
Wing tip rib shown. The hump on both
should be facing upward.

Rev: 2012.11.04.v004a 11
Lay down a bead of Welders into the
rib and spar areas. Lower the assembly
into the provided slots allowing any
extra glue to squish out.
The short spar should be buried in the
middle section and the long spar
should be flush with the bottom of the
wing. The humps in the ribs will stick
out on both inner and out ribs as
shown.
Fill any voids with glue and wipe up as
much excess glue as possible.
Remember we want to keep things a
light as possible.

Rev: 2012.11.04.v004a 12
Weigh it down flat on a flat surface and
let it dry completely. Pay special
attention to ensure that the wing is flat
and the spar is straight and true.
Get ready to install the elevator. Put
Welders on the end of the Fuse and let
it tack up.
Put Welders on the elevator, spread
thin, and let it tack up.

Rev: 2012.11.04.v004a 13
After tacking for a few minutes
assemble the elevator to the fuselage
piece. Notice there is a tab on the stab
and fuse that will keep you from
putting them on backwards.
Assembled elevator to fuselage.
Now install the lower part of the
fuselage. Put Welders on the tabs and
flat spots of the lower fuselage

Rev: 2012.11.04.v004a 14
Put Welders in the tab slots and flat
spots between the tab slots on the
horizontal fuse piece. Be cautious not
to put Welders in the servo hole areas.
Put the lower fuse onto the horizontal
fuse piece while the glue is wet. Make
sure it is 90 degrees to the horizontal
piece and clean up all the excess glue.
While the lower fuse is drying we will
install the aileron control horns. There
are two different shape control horns in
the kit. The ones angled the same as
the hinge line of the ailerons are the
correct ones.
Aileron Control Horn

Rev: 2012.11.04.v004a 15
Put Welders on the control horn.
Install the control horns while the glue
is wet and let dry. You may have to cut
out the EPP fuzz in the slot in the
wing to get the horn to sit flush. Trial
fit before gluing.
Also while the lower fuse and control
horns are drying, fold over the ailerons
and weight them down for a few
minutes to loosen up the hinges.

Rev: 2012.11.04.v004a 16
Install the upper part of the fuse.
Put Welders on the tab slots and flat
part of the fuse.
Put Welders on the flat parts and tabs
of the upper fuse piece, insert wet and
let dry. Take care to make sure the
upper fuse is in line with the lower fuse
and 90 degrees to the horizontal fuse
piece. Also make sure the front of all
the fuselage pieces are flush. This will
be important when mouting the motor.

Rev: 2012.11.04.v004a 17
Clean up any excess glue.
While the upper fuse is drying put
Welders on the canopy area and let it
tack up.
Put Welders on the canopy itself and
let it tack up.

Rev: 2012.11.04.v004a 18
After the glue has tacked up, attach the
canopy to the fuse. Make sure it is
going in the right direction!
Put Welders on the Fuse find side and
let it tack up.
Put Welders on the fuse fin side and let
tack up. Put Welders on th fin and let
it tack up. No need for glue in the
elevator joiner area where the half
circle is cut out.

Rev: 2012.11.04.v004a 19
While the glue tacks up install the
control horn in the rudder the same
way we did with the ailerons.
Rudder Horn
After the Welders has tacked up glue
the rudder to the fuse. Start at the top
so you can manage the fin to rudder
gap and work your way down.
While everything is drying, take the
time to keep tweaking it so that
everything dries perfectly straight.

Rev: 2012.11.04.v004a 20
Now you can install the elevator
control horn.
Elevator Horn
Now install the side trusses.
Cut one of the tips off the trusses so
that you can run the servo wires from
the tail servos out of the and tuck the
wires back into that space after it is all
finished to clean up the radio install.