Sonex Cowling Installation Instructions - Manual (Page 2)

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Builder's Guide
__3. Hold the aft edge of the cowl against the fuselage side
skin and mark the trim line on the cowl so the aft edge
of the cowl will match the angle of the forward fuse-
lage. Generally, approximately 1" needs to be removed
from the rear of the cowl.
When properly fit the lower corner of the cowl will flow
smoothly into the lower edge of the skin (Left photo). The cowl
in the right photo still has too much material and can likely be
trimmed further.
__4. Remove the cowl and trim the aft edge of the cowl to
match the angle of the forward fuselage. A fine-tooth
pull saw works well. Touch-up can be easily accom-
plished with a long piece of aluminum channel with 180
grit sandpaper attached.
__5. Once the cowl is properly trimmed to match the side
skin, the piano hinge for that seam can be installed.
Drill through the side of the cowl using the pilot holes
in the hinge as your guide. Clecos will hold the hinge
half to the cowl until the entire cowl has been fit.
__6. Cut the clearance slot
for the piano hinge as
detailed in the plans.
__7. Re-install the cowl half and attach it to the hub spacer
and fuselage side.
__8. Clamp the top of the cowl to the cowl strap with
a swivel pad vise grips or, alternatively, install the
(Southco) fasteners that will secure the top of the cowl
to the firewall.
__ 2. Attach the cowl to the spacer with drywall screws. The
cowl should conform to the edge of the spacer. If it
does not, make sure the cut-out for the prop hub is large
enough that the cowl is not in contact with the hub, and
make sure the hub spacer is properly made.
Important: The cowl should extend to or beyond the
vertical centerline of the prop hub spacer. If it does not,
investigate the cause.
Cowling Installation
Rev N/C 07/13/08