Extreme Flight 104 Laser EXP ARF, Assembly Manual

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Rudder and Center of Gravity location
11. Locate the rudder and associated parts bag. This Laser has a removable rudder, as such the
assembly is simplified from what you may be used to. The hinges are already glued in so
we may proceed to installing the rudder. Install the long pin to hold the hinges together,
this installs on the top of the rudder. The pointed end goes down thru the hole on top of
the rudder and you may have to work with the rudder to get it thru all the hinge holes.
Push it all the way down till the threaded portion is in the hole and against the female
threads. Use a small straight screwdriver to tighten and add BTL, you may consider
running the tailwheel tiller thru the ball link at this time. Next I suggest we find your CG,
in our prototype models a tail mounted rudder servo in push pull configuration yielded a
perfect CG. However, ours utilized the DA120 on stock mufflers and your setup may
differ in weight. Therefore you will need to put your wings, horizontal stab/elevators and
all accessories (batteries/switches/regulators etc) that you intend to use in their respective
places, refer back to figure 24 if needed for how we laid out our model. The rudder servo
has a bay on both sides of the fuselage near the very rear. Locate these bays and decide
which side to use and secure the rudder servo and hardware with tape or similar to the side
of the fuselage exactly where it will mount and attempt to find the CG. The CG range is
front of the wing tube to its’ rear with the ideal range being ½ to ¾ rearward from the
front of the wing tube. If your CG is close to the desired range remember you can move
batteries or other items around to achieve a desirable CG. The goal is to have a rear
mounted rudder servo, but if desired CG is not attainable then move the rudder servo to
the tray in the middle of the fuselage and attempt to get your desired CG. Once you have
the desired CG location then mount your servo there. If you ended up in the rudder tray
then a pull pull is how the rudder will operate and hardware is supplied for that
installation, but since the most likely is a rear mounted rudder servo we will cover that
style of installation. With a rear mounted servo we chose the right side of the fuselage and
used a single servo (MKS 777A+) and found it to give plenty of authority for all
maneuvers, but a dual rudder servo can be used. I will continue with explaining a single
servo install. If you are using a single servo installation then use the same method we did
with the elevator/ailerons. If you choose a dual servo aft or pull pull rudder tray setup then
you will need to find the laser cut rudder control alignment tool. It is two pieces of thin
plywood and you will install your control horns then use the alignment tool to keep them
in place while drying, see figures 29 and 30 for this process. We chose to mount our
rudder servo on the right side of the fuselage. Locate that bay again and cut the covering
as desired and mount your servo with the output shaft oriented to the front of the plane.
This will require a 48” servo extension and we highly recommend the EF extensions since
they are 20AWG and have universal connectors. There is also a Carbon tube to route your
wires thru and we recommend using this to keep your extensions from flopping around
during flight. If you have not put your elevator extensions in the tube (also 48”) I
recommend threading all 3 extensions at the same time for ease of installation. Consider
labeling them to make future connections easier. Now you can thread your ball links onto
the pushrod and continue with the final installation in the same manner as the