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this section, as it will significantly reduce the strength in the longerons in a highly stressed area. Do
some final cleanup sanding to finish blending the fuselage and noseblock together, and then seal
the noseblock with three coats of nitrate dope to seal, including the back faces.
Final sand the fuselage box assembly to remove all mismatches between the longerons and other
members. Finish with 220 and 400 grit sandpaper, then coat with two coats of nitrate dope, sanded
with 400 grit paper between coats. Dope the inside surface of the nose area as well.
Cover the fuselage with tissue, attaching to all the cross members as well as longerons. This type
of fuselage will eventually see lots of tissue repair with use, and having the tissue bonded to the
structure in cells will make this aspect much neater and faster to accomplish. Shrink the tissue and
finish the fuselage with two coats of thinned non-tautening nitrate dope. Cement the two F-5 wing
rails onto the top longerons where shown on the drawing. For a finished look, cover these with
tissue strips to match the fuselage color after bonding in place.
Install the 1/16 aluminum D/T guide tube on the end of the tail filler block using a spot of thick
CA at the top and bottom, dusted with microballoon filler. Install the two 3/32" scrap balsa
D/T band stops on the bottom of the fuselage as shown on the side view. Reinstall the
incidence adjustment screw in the tail filler block.
Stabilizer Rigging
The rig of the horizontal stabilizer is somewhat critical in plan view. The effect of having two
vertical stabilizers mounted off center to the fuselage means a high degree of turning force for
small angular changes in the horizontal stab position. For this reason, the keys shown on the
strike plate are necessary to insure consistent trim of the model. Without, little variations in
seating the stab on each flight will likely result in inconsistent turning performance, and some
frustration on the part of the builder to get the model in trim.
Using 3/32 scrap material, make a small block with tapered sides to match the size of the
plywood strike plate already installed on the bottom of the stabilizer. Bond this in position
over the strike plate.
Position the stabilizer assembly on the stab platform and determine as best you can an
equalized position for the two fins, as close to parallel to the fuselage center line as you can.
It is possible to set the stab slightly skewed such that the right tip is slightly forward of the left
tip for built in right turn trim if you so desire, but we recommend setting up with a parallel
condition to start and leaving rudder tab adjustments as a last resort to obtaining a right hand
glide pattern. Once the position is obtained, press down carefully on the trailing edge of the
stab to allow the head of the incidence screw to make an impression into the balsa block
glued to the strike plate. Allow the stab to tilt up, and using a new sharp razor, carefully make
a forward / aft slot in the block to the width of the screw head impression. Test the fit of the
slot over the screw head, and keep lightly cutting the slot until it is wide enough to snugly grip
the screw head, and deep enough to let the screw head hit the strike plate. Use a small file
or emery board to develop a tight but slipping fit of the slot with the screw that allows the stab
to pop-up easily upon D/T release, but with no lateral slop that would impact the turn trim of
the model. Once this accurate fit is obtained, you can carefully sand down the thickness of
the keys to be no taller than the thickness of the screw head.
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D/T Timer Setup
