Jabiru J450 Constructors Manual
Pre-Paint>Fuselage>Firewall forward>Fit firewall
Tuesday, April 6, 2010
44 of 343
Pre-Paint>Fuselage>Firewall forward>Fit firewall
Objectives of this task:
To fit the stainless steel firewall plate to the fuselage. This task will require accurate
measuring and bending of the firewall plate: it is possible to make an accurate bend by
clamping the plate to the edge of a solid workbench between 2 lengths of heavy angle iron
and use a solid length of timber or heavy angle iron to press the bend to a tight radius, but for
a small fee many plumbers or sheet metal shops will bend the firewall plate for you, and
provided that your markings are accurate this may be a good choice for many builders.
Note that the bends required are not sharp creases but rather tight radius (3mm) bends of 55°,
which is the same type of bend that a plumber‟s sheet folder will make.
Materials required:
Firewall plate (stainless steel)
Dow Corning silicone sealant (dark green tube in kit – shown above right)
Firewall insulation sheet (white roll in kit – shown at right)
38 x 73 AS 5/32” rivets and matching washers
Mark and bend the firewall plate
The technique that we use in our factory is to temporarily mount the firewall near the lower
bend with 2 self-tapping screws and mark the centre of the bend points, then bend the plate.
Start by having someone help you to position the plate so that the bottom centre of the plate is
level with the bottom of the fuselage and the plate is equally spaced side to side. It is
important that the plate is positioned the right way around: the small holes must be in the
upper left and the larger hole must be in the upper right when viewed from the front. Refer to
the photo above left as an example of the correct positioning.
Drill a 3/32” hole through the plate and into the plywood firewall each side (as arrowed in the
photo at above left) and fit a self-tapping screw, then mark the
centre
of the lower bend on
each side (as circled at above right). Bend the plate slightly back at the lower bend as a
reminder of the correct bend direction for later when you bend the plate.
Level here
screwed here
Large
hole
Small
holes