4 PLACE FINAL ASSEMBLY SECTION
WING INITIAL ATTACH
One of the most important operations in the final assembly is the attachment and
line up of the wing panels. For this operation it is recommended that you provide
a clear open area sufficient for mounting both wing halves at the same time, and
that it be reasonably level and provide adequate working space around the
perimeter. Since you will be attaching and removing the wing sections several
times, it is suggested that you determine the minimum length of main spar bolt
for just s few turns of thread engagement, and washer the head end of the bolts
to this limited length. This will minimize wear and tear on the locking section of
the secured nut, and give you a better feel for the tightening forces clamping the
It would be a good idea to level the fuselage assembly in both axis at this time.
Check the spar faces to assure yourself that the BID pads have been added to
the main spar mating surfaces to avoid unintended “sweeping” of the wing angle.
It is acceptable to have installed the BUTT LINE 46 pads on either the wing spar
section or the center spar outer face – just so the total build up is the same at
both butt lines such that the assembly has been “shimmed” straight.
Check the mating surfaces (rear face) of the center spar for angle at all four of
the bolting positions (left and right butt lines 22 and 46). If the spar has been
properly assembled with no twist, all these faces should be roughly 3 degrees
from vertical (tilting aft) and parallel within about a half degree. Any small
amount of deviation from the other surfaces (twist), can be corrected by adding
some staggered plies of BID, and faring the surface with FLOX.
Use considerable care when sliding the open end of the wing on the stub spar
extending from the fuselage side. You have incredible leverage at the wing tip,
and lifting or lowering the tip excessively could easily tear the wing skins loose in
this area. Some trimming will be required at the end of the spars to allow full
insertion of the wing sections. Strive for roughly ¼ inch clearance between the
end of any spar, and the fuselage outer skin, or any other potential interference
The procedure that has worked best for us is to start the inboard bolt through
both spar bushings first, and the carefully raise and lower the tip, and shaking it
slightly to start the outer bolt. Snug these bolts up just enough to eliminate
perceptible looseness between spar faces.
Repeat this process for the other wing half.
WING INCIDENCE CHECK AND SET
The nominal wing incidence angle relative to the zero waterline is a positive 3
degrees (leading edge higher than trailing edge). However, more important than
this exact value is that the angle of the two wing sides be the same. If you are up
or down one degree on the absolute incidence angle it only really changes the
flying “deck” angle slightly with a small effect on drag and trim conditions.
However, if you have this kind of variation between sides, you can induce a large
“roll” input, which would have a very negative impact on control limits and out of
Carefully recheck the level of the fuselage in both directions. The general rule of
thumb for this level check is to use the cockpit edges.
If you do not have an airfoil template gage with the three degree angle reference
fabricated, make one up at this time. If you have lost or damaged the full scale
airfoil drawing, contact the factory, and we will send you a new one. This
template should be made of sufficiently rigid and durable material (plywood,
masonite, etc) such that it can be placed on the wing upper surface and support
a level on the 3 degree reference line.
Check both sides in their present bolted on condition, and verify that you can
displace them to the referenced 3 degree position. As mentioned before – SAME
angle is more important than exact angle, and if on panel cannot be exactly
pushed to this position determine the angle that can be attained on both panels.
If this angle is within 1 degree of standard, record this angle and make them the
same on both sides.
There should be some separation between adjacent faces on the rear spar
(about ¼ inch). DO NOT clamp that spacing closed. Make up a free fitting shim (
of plywood, Masonite, fiberglass, or other material with good compressive
properties that you can drill though in a subsequent step)of the appropriate
thickness and “tack” bond it to one of the surfaces.
Line up, and secure the position for the proper incidence angle, and pilot drill
(clearance for a #10 bolt) through the two spar sections. Locate this hole inboard
of the flap bearing hanger, and roughly centered in the two parts. Make sure
there is sufficient edge clearance for the aluminum “hat” shaped bushings which
will be subsequently installed . Also, be sure to verify that the position of these
holes will not be blocked by the flap actuation torque tube.
Secure the first side with a snugged up #10 bolt and nut, and recheck angles
before drilling the other wing panel in a similar fashion.
Locate and select the 4 bushings to be installed and enlarge the holes to accept
these bushings. Verify that the bushings are not too long, such as to protrude
from the mating surfaces, and proclude proper clamping. (trim if required)
Coat the bushing surface to be bonded with Hy-Sol or FLOX adhesive. Lightly oil
the bolts to be used, and separate the two spar faces and the selected shim in
the local area with waxed paper or plastic to avoid inadvertent bonding of these
Install the bushings using the proper diameter bolts (5/16 in), and lightly clamp in
place (use a non locking nut at this time, and just a bit more than finger tight).
Confirm that the bushing flanges are down snug on the part surface.
Locate and drill the ½ inch diameter holes through the rear spar of the wing, and
the fuselage stub spar, for the rear spar bushings. This also should be drilled in
conservative steps to provide a clean accurate hole. Again use ½ inch hardware
store bolts for temporary alignment.
UPPER WING ROOT FAIRINGS
With the wing panels temporarily installed on both sides, fit the flaps in place, and
position them in the “up” position by using the airfoil template to determine true
Test fit the fairing moldings on both sides. Note the fit to the fuselage sides and
have someone sight from the front and rear to assure that they will be the same
on both sides. You should have a minimum bond area of about ¾ inch, If
trimming some of the edge makes a better fit, this may be done so long as this
minimum bond width is maintained.
Drill some small pilot holes (about 1/16 in for screws or proper diameter For
clecos) through the fairing flange and into the fuselage skin. Temporarily attach
with small sheet metal screws or clecos. Mark the upper edge of the intended
Fit up the lower trailing edge section of the fairing, observing and clamping the
trailing edge joint. If the outer flange on this part is adding too much thickness
above the flap surface, it is permissible to cut off this flange, and recreate it
facing inward with about 2 or 3 ply BID.
Also mark the bond areas for this lower fairing section.
Remove the fairings and thoroughly scuff the bond areas on both parts with
coarse (# 36 or similar) sand paper.
Mix a batch of FLOX to a pasty (adhesive like) consistency and coat both
surfaces to be bonded (inner surface of the fairing and the fuselage side).
Secure fairings with sufficient screws or clecos to make a smooth edge with the
fuselage skin. Clean off surplus adhesive which has squeezed out, but leave a
fillet at the transition edge for sanding later. It might be a good idea to tape or
otherwise secure the other edge on the upper wing surface to avoid buckles and
waves. If a severe buckle is evident, it is possible to slit the edge, place plastic
beneath it and glass tape the cut.
After the adhesive cures sufficiently, remove the screws and/or clecos, and clean
up the edges. The trailing edge joint between the upper and lower fairing
sections is subject to vibration, and is a difficult joining surface. A wrap of BID
tape (or locally procured lightweight glass cloth) can be a “belt and suspenders”
treatment in this area.
SETTING FLAP POSITION
If the small plastic square that rides in the flap actuation “track” is deliberately
drilled slightly off center, it can be a possible adjustment mechanism to assure
symmetrical flap position. A side offset of roughly .020 in. and a vertical offset of
.040 in. will give you up to .08 inch of corrective travel if required in .02 in,
increments by relative rotational position of the blocks on each side. More
severe corrections can be obtained by greater offsets, but the actuation arm may
interfere with the sides of the “track.”
When the two flap sides are equal, it is a simple matter to adjust linkage length to
place the flaps in proper position for normal flight (as checked by the airfoil
Actuate the flaps through full travel, and clear any interference problems and
assure free and positive operation.
ADJUST AILERON RIGGING
Verify that the sticks are centered, and the aileron idler bellcranks in on the
fuselage wall are in the proper position (these positions determine the aileron
differential and are important for proper flight characteristics, and “feel”.)
The original drawing of the control linkage in the fuselage section was in error,
and if it has not been previously corrected make these changes. The offset in
the aileron idler link is intended to be an element in the linkage system to
increase aileron differential to reduce adverse yaw, an slightly reduce aileron
actuation forces – but I drew it in backwards, which would actually counter the
differential effect of the aileron bell crank. To correct this, reverse the location of
the idlers – put the one shown on the right side over on the left side etc. The
new rigging angles are set by swinging the link inboard such that the lower hole
is roughly 5/8 inch inboard of perpendicular (ref sketch).
For those of you that have sized the push tube going out to the wing – this will
result in almost the exact same length setting. The link to the control stick (made
from ¼ inch threaded rod) will now be shorter, and may have to be cut (measure
twice and cut once). The rod end of the short rod from the stick, should be
mounted on the forward face of the link, and the rod end from the wing on the aft
face (remember to use the large area washers to capture the overhung side of
the rod end). The offset to the two faces induces a small amount of torque into
the arm, but it provides better line up and avoids interference between the two
rod ends Observe the rise and fall of the tube in the leading edge of the wing,
and assure that there is no interference to travel. The link position may have to
be adjusted a bit rearward if possible, or a spacer beneath the rod end at the link,
to move the tube a bit aft where there is more vertical room.
The enclosed picture shows the relationship of the aileron idler link, and the
control stick on the left (pilot’s side) looking forward. The 30 degree travel shown
is the approximate maximum allowed by the stick travel stops. In most
installations the counter weights on the aileron will limit the travel to roughly 8 or
9 degrees in the downward direction and about 13 or 14 degrees upward. Some
minor increase in travel can be provided by cutting away the inner surface of the
skin sandwich panel in a local area, but the above values should be sufficient,
Adjust the rod between the ailerons and their respective outer bellcranks such
that the long arm of the aileron bell crank is parallel to the direction of flight when
the ailerons are in neutral.
Adjust the aileron rod lengths to satisfy these conditions at rest. The ailerons will
“fly” up just a little under flight loads, and that is just fine.
CASTERING NOSE GEAR ASSEMBLY
Many of the four place kits are now being provided with a castering version of the
nose gear, much like the very successful new two place gear. These gear
assemblies are shipped almost completely assembled and ready to install. The
basic approach is to
use the assembly as
a template for
drilling the required
through the fire wall.
Place the nose gear
assembly roughly in
place on the firewall
as shown in the
Center the top
bracket at roughly
the expected height,
and secure with
tape or other
Set the gear leg
vertical to fuselage
centerline, and push
the linkage and “L”
shaped brackets up into position. Raise these legs up until one or both are
limited by the inner “bend” radius contacting the lower edge of the firewall. Both
brackets should be at roughly the same height, but the position of the assembled
linkage is more important than for both to contact the bottom edge of the firewall
simultaneously . However if there is a great difference side to side recheck your
positioning before drilling any holes, and contact the factory if you cannot resolve
this problem. Verify where the bolt holes will break through the back of the
firewall and ensure that clearance exists for a generous washer, and no other
components will be damaged when the holes are drilled.
When you are assured of this positioning drill clearance holes and install
appropriate 5/16 bolts nuts and washers. To temporarily secure this part of the
assembly (the top bracket should still be only temporally retained in position)
With the fuselage supported, and no weight on the gear leg, the upper bracket
should be positioned vertically such that the outer end of the lower “H” link is
roughly one inch below horizontal. Check the back side of the firewall where
these upper bolt holes will come through to assure that fiberglass stiffening lay-
ups are present. Also check the location of the wheel when the assembly is
suspended in this position to estimate the static height of the front of the airplane.
With the static load we would expect roughly one inch of strut compression and
about a half inch of tire deflection. Under static conditions the aircraft should sit
just a few degrees nose high. If either of these conditions appear seriously
amiss we would suggest you contact the factory
When the vertical position is established use the bracket as a template and drill
clearance for and install two 3/8 inch bolts nuts and washers to attach the top
MOUNTING THE WHEEL
The wheel can be mounted at any time, but may be advantageous to delay it to
reduce the weight of the assembly during handling and mounting. The wheels
being shipped at this time employ tapered roller bearings which require a preload
for proper operation. Four Belleville spring washers are used in the installation to
provide an adjustable preload. Two washers are installed on each side of the
wheel “flare to flare” as shown on the sketch. A tubular spacer is also installed on
each side as shown and the center bolt tightened to compress the spring
washers and load the bearings. Torquing the bolt all the way down may provide
excessive preload for too much friction and premature bearing failure.
The rubber seal on the bearing may mask the proper preload, so lubricate this
seal and rotate the wheel numerous times to get the preload which secure the
inner race from rotating on the axle but not overload the bearing.
CASTERING NOSE WHEEL YOKE
This item should come installed but if it is disassembled for any reason note the
relationship of the spring (Bellvile), and plain washers for proper reassembly.
Check the pivot friction regularly, particularly during early operation as it breaks
in. It should take a fairly vigorous push (about 15 to 20 lbs.) at the axle location to
pivot the assembly. If shimmy is noted during operation, check the tension in this
assembly to assure that friction is present for damping. Friction is increased by
tightening the castellated nut (be sure and replace cotter key).
Swiveling of the nose wheel yoke is limited by the three roll pins (two on the
yoke, and one on the gear leg). Some early gears were shipped with 3/16 inch
diameter pins, which have had durability problems. If this is the case on your
assembly, it is suggested that they be removed with a vice-grip or similar tool,
and ¼ inch diameter pins fitted.
The aluminum yoke sides provide a wide choice of locations for drilled and
tapped holes for fastening the front wheel pant. The drag of an unfaired nose
wheel is very high so close attention to this area will help in cruise speed and fuel
economy. The installation of optional wheel fairings is covered in a later section.
Configuration of that part of the fuel system which lies aft of the firewall will be
very nearly the same the same for any Cruiser regardless of engine selection.
Components to plumb the basic fuel to the firewall have been provided with the
kit. However, some engine installations require a return flow provision which may
require hardware not included with the basic kit.
Configuration forward of the firewall will be dependent upon the engine to be
used plus many other factors. Therefore components to build that portion of the
system must be defined and provided by the builder.
Before proceeding with work on the fuel system it might be a good plan to read
the book “Firewall Forward” by Tony Bigeles, or a similar reference. These
documents have countless techniques and ideas that can prevent disaster at a
Fuel from each wing tank is carried by a short length of 3/8 I.D. neoprene hose to
a bulkhead fitting at the side of the fuselage. A length of 3/8 O.D. aluminum
tubing carries the fuel to each side of the selector valve and another tube then
takes it forward to the bulkhead fitting on the firewall. The selector valve
provided has a left tank, and a right tank position,, and off. Selectors with a
“both” position are not recommended for low wing aircraft of this type.
After passing through the firewall the fuel goes via 3/8 aluminum tube to an
electric boost pump and then to the gascolator. A flexible fire-resistant hose is
suggested to carrythe fuel to the engine-driven fuel pump.
WING TIP INSTALLATION
Prepare the pre-molded polyester and fiberglass wing tips for installation. Cut two
trailing edge ribs of ¼ foam using the template supplied. Install each rib about 7/8
inch into its tip so as to allow the tip to slide over the joggle end of the skin. The
rib should butt up against the aft spar face. Apply one layer of BID to each rib to
keep them in place and help them hold shape. Check fit the tips onto the wing
panels. The joggles on the skins help make them fit flush.
The wing tips are fabricated with polyester resin, and it is possible that some
distortion may have been introduced during shipping or storage. In some cases
it may be necessary to slit the trailing edge of the wing tip molding to properly
align the tip. Make numerous dry installations to assure proper alignment before
If everything is okay use a thin mixture of resin and flox to bond the wing tips
permanently in place. Be sure to tape or screw the tips in position so they don’t
shift while the flox is curing. Stand back and make sure they are properly aligned
before cure; a “bent” wing tip would really be an eyesore, and could adversely
impact the trim of the aircraft
An alternate method of attaching the tips is to leave them removable. If this is
desired attach each tip with equally spaced AN507-832-8 csnk.. machine screws
( at least six top and six bottom) and K 1000-832 anchor nuts. The alternate
installation hardware is not provided.
OPTIONAL WHEEL FAIRING ASSEMBLY
Note: Wheel fairings are not provided in the standard Cruiser kit. These
instructions are provided for those builders who purchase the fairing kit at extra
MAIN GEAR FAIRINGS
With an aircraft of the speed potential of the Cruiser, the wheel fairings become
a very valuable option, adding 5 to 10 mph to the cruise speed at the same fuel
burn. However, a poorly installed set of fairings can quickly become a greater
bother than a benefit.
Carefully trim and fit the wheel fairing to the wheel, centering it to avoid rubbing
on any surface, and provide enough wheel protrusion below the faking to suit the
type of landing surface where you will be operating. There should be enough
wheel showing such that even with a flat tire and in landing attitude, the faking
will not strike the surface. Refer to the pictures on the next page and fabricate a
bracket of aluminum sheet at least .080 thick as shown to retain the inner side of
the wheel fairing. (It may be advantageous to make the bracket flat rather than as
shown; in this case the bracket will clamp between the axle and the gear leg.)
Use the upper two axle bolts for attachment, and drill and tap the gear leg #10-32
for two additional bolts if desired for added rigidity, secure to the fiberglass wheel
fairing with two #10-32 bolts at each end. Verify location and length of bolts for
clearance to the wheel and tire. Nut plates can be added to the fiberglass part for
ease in assembly and disassembly
For support to the outer side of the wheel faking, drill and tap the end of the axle
above the centerline to avoid the cotter pin hole. A ¼ inch threaded rod is
suggested for this support. Use a jam nut to secure it tightly to the axle, and
another nut to space out the fairing shell. Use an area washer inside the surface
of the shell, and a self locking nut on the outside of the faking. An area washer
here would ad d structural support, but is probably not required. Trim excess rod
for a neat looking job with minimum air drag. Supported on both sides in this
manner, the fairing should almost be secure enough to stand on.
Trim and fit the back cover of the fairing assembly. Position and drill 6 holes for
securing it to the main fairing body. Verify the length and position of the securing
bolts such that they will not rub on the wheel or tire. Install #8-32 nut plates at
these locations and bolt into place with #8-32 screws. Again verify that the
screws are not excessive length and will not drag on the wheel.
Make note of the complexity of assembly and disassembly and decide if you are
going to provide a hole for tire inflation. If so cut it before painting. Electrical
supply houses frequently sell plated metal cover plugs with spring fingers for
closing access holes in electrical equipment., and you might consider these as
The nose gear fairing is equally important, and presents a slightly different
challenge. This gear must be free to swivel to permit steering on the ground, and
the interface with the gear leg fairing is an extra place of concern during the
The nose gear fairing comes as a two piece assembly split roughly in the middle
lengthwise of the section. Position the half with the positive overlap (right side),
locating the desired placement of the wheel axle and the orientation of the fairing
to the ground level. The wheel fairing halves may have to be drilled to clear the
ends of the axle. Be sure you have verified the desired position before drilling
these holes Also note the location of the gear leg pivoting action to assure
proper steering of the wheel without interference with the gear leg fairing (it might
be prudent to test fit this fairing at the same time). locate one attach bolt as far
forward as practical on the flat surface on the side of the “shoe” (pivoting wheel
fork). A shaped “shim” of Bondo or dry micro can be used to match and space
the inner surface of the wheel fairing to the side of this “shoe”. Center the fairing
longitudinal seam with the centerline of the tire during this fitting. The material of
the side of the “shoe “ can be tapped for the attaching thread - we suggest a
#10-32. Another attach bolt and “shim” should be provided back near the axle (be
sure that the bolts extending through this surface will not rub on the tire or wheel
-watch both positioning and trimmed length for this). If the attachment holes are
tapped as suggested rather than using self locking nut plates, remember to use
Loktite or similar thread securing compound in final assembly.
Temporarily attach the other half, and locate a similar pair of bolts and “shims” in
symmetrical locations. Double check at each step to assure that the proper
alignment is being maintained, and trim away or add shimming material as
As before, decide if you are going to provide a hole for tire inflation, and if so
locate in the desired position and cut hole before painting.