Top Flite Metrick - Manual (Page 11)

COVERING
Earlier in the introduction, we spoke of design criteria and
in the #1 statement "airfoil efficiency" and "clean aero-
dynamics" were mentioned. The METRICK was designed
to be a clean, relatively fast two-meter sailplane and
while the basic shapes have been provided, what the
airplane is covered with is certainly an issue. Airframe
cleanliness and full flight potential is realized by using
Monokote for this airplane. You will need two rolls of
Monokote for the METRICK, leaving some left over.
Cover each of the separate components; wings, stab
halves, rudder, canopy/hatch, access hatch and fuselage,
also cover the spoilers separately if you have built this
option. Follow the instructions provided with each roll of
Monokote. Remember, to keep it simple, light and beauti-
ful, keep it Monokote!
After covering, your spoilers and access hatch are hinged
using Monokote Trim sheets with the "wet" adhesive.
Carefully slot the fin and rudder and epoxy these hinges
in place ("flex" them a few times first to free them up) on
first the rudder and then the fin—wipe off any excess glue
with acetone. Locate and install the nylon rudder horn
using the two #2 wood screws provided. Install the
towhook and secure as shown on the plans.
If your flying site isn't grass you may wish to protect the
bottom of the fuselage from "gravel rash" by the addition
of a rubber-type skid strip. A length of this material
extending from in front of the towhook forward to the
nose works quite well. This self-adhesive material can be
found in most automotive supply stores. There are also
commercially available skid strips sold in hobby shops,
Airtronics is one of the manufacturer's who make it
available.
RADIO INSTALLATION
The radio installation in your METRICK is very straight-
forward and therefore should not present a great many
problems. As the plans show, the design is set-up for
standard configuration 500 mah battery packs with room
left over for any ballast required to arrive at the proper
C.G. (Center of Gravity). As shown on the plans, the
battery pack should be installed in the forward-most
compartment of the fuselage, with the connector harness
facing aft. Small, custom cut pieces of foam rubber are
used to securely nest the pack in place—pack firmly, not
tight, to avoid any shifting. Remember that this compart-
ment will in all likelihood have to receive a small amount
of ballast (lead) to achieve the C.G.
The compartment directly behind the battery pack is
used for the receiver. In our METRICK's, we mounted the
receiver in place on its' side, leaving quite a bit of room on
the other side of this compartment which was used for
the switch. If your antenna is not internally mounted,
simply drill a 1/16th hole in the side or bottom of the
fuselage, route the antenna through this hole and aft back
to the rudder post area where you can secure it with a
rubber band and a small hook made from a straight pin.
The servo compartment, as shown, is directly behind the
receiver. This area is used to house the flight control-
rudder and stab—servos. Note that the servos shown on
the plan are reversed to one another for optimum servo
output wheel clearance. In the case of radio systems that
have a servo reversing feature, this presents no problem.
If your radio does not have this feature, then you must
first determine the direction that your servos go to
achieve the proper surface directions upon radio com-
mand. The servos must then be mounted correctly into
the fuselage. As noted earlier, the leftover piece of 3/32" x
1/4" ply strip that was used for the stabilator roots should
be used for the two required servo mounting rails. These
should be carefully cut to fit accurately between the
inside fuselage sides and on top of the 1/16" x 1/4" balsa
servo rail locators that were glued in place during fuse-
lage construction. Locate and epoxy the forward rail in
place first, as close to former F-5 as possible. Trial-fit one
of your servos in place with the forward mounting lugs
resting on the forward servo rail. Slip the rear servo rail in
place with the rear mounting lugs of the servo resting on
it. This will locate the position of the rear servo rail—mark
its location in pencil on the inside of the fuselage, on each
side, remove the servo and epoxy the remaining servo
rail in place.
While the METRICK's radio compartment was specific-
ally designed to accept most radio systems currently
available, the servo output arms for some systems may
require some trimming or modification in order to clear
the fuselage sides during their movement cycle. Once
you are satisfied that the servos move in the proper
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