Carf-Models Ultra Flash, Instruction Manual

Page: 6 / 44

4
area when moving downwards.
The slot needs some explanation, too. The cut line is
exactly in the correct position so that the control surface
slides under the wing skin smoothly. If the cut was a few
mm forward or backwards, it would not work properly. So,
make sure that the lip is not damaged, and that the control
surface slides under this lip perfectly. It will
not lock at any
time, as long as the lip is not damaged. If damage occurs,
you can cut a maximum of 2-3 mm off the lip on the wing in front of the control surface, but you
should
never
cut off more than this.
Servo Choice:
We strongly advise that you use the recommended high-torque digital metal-geared
JR/Graupner servos on all the main flight controls, and the milled plywood mounts are specifi-
cally designed for these.
The elevator servos cannot be thicker than 19mm, otherwise they will not fit in the stabiliser,
and we have used JR8311 in all our prototypes without any problems.
The ailerons are very large surfaces, and the shock-load on the servo geartrain in a ‘hard’
landing is quite severe - so please use a metal geared servo like the JR8411 for these.
A good alternative for the ailerons, flaps and rudder is the Futaba S9351, but this servo is too
thick to fit in the stabiliser. See the recommended servo list on page 6.
Servo Screws:
Fix the all the servos into the milled plywood servo mounts using the 2.9 Ø x13mm or 16mm
sheet metal screws provided in the kit, not the standard screws normally supplied with servos
by the servo manufacturer. This is because all the holes in our milled servo mounts are 2mm
diameter, due to our CNC manufacturing process, and this is too big for the normal screws.
Building Sequence:
The actual building sequence is your choice, but it is definitely most efficient to start at the
back of the fuselage and work forwards, in the same order as shown below.
Take Care:
Composite sandwich parts are extremely strong, but fragile at the same time. Always keep in
mind that these contest airplanes are designed for minimum weight and maximum strength in
flight. Please take care of it, especially during transport, to make sure that none of the critical
parts and linkages are damaged. Always handle your airplane with great care, especially on the
ground and during transport, so you will have many hours of pleasure with it.
To protect the finished paint on the outside of the model from scratches and dents during build-
ing, cover your work table with a piece of soft carpet, cloth or bubble-plastic. The best way to
stop small spots of glue getting stuck to the outside painted surfaces is to give the whole model
2 good coats of clear car wax first,
but of course you must be sure to remove this 100% proper-
ly before adding any additional paint, markings or trim.
Centreline of hinge axis
Phenolic control horn