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fuselage frames touching the forward blocking.  Do a check on the aft end of the fuselage for being
even when held together on the centerline of the plan view.  When you are comfortable with the
best fit of all the features and rig of the two side frames, bond the lower cross members in place
with thin CA, used very sparingly.  Add the upper cross members at the same fuselage stations you
just bonded, maintaining squareness to the building board surface and match to the drawing plan
view. Use white glue or cellulose glue to allow these to be positioned carefully.  Make sure the
fuselage side frames are held against the building board on the flat section, and supported evenly
at the aft end to insure no twist can develop, and allow the constant cross section area to dry
before attempting to install additional cross members.

Using blocking to maintain squareness to the building board, lightly bend the fuselage sides to the
plan view and fit of the variable cross members, working one bay at a time, starting with the first
bay forward of the constant section already bonded.  Pin the back edge of the blocking to keep the
fuselage sides bowed and in contact with the upper and lower cross members, matching the plan at
each cross member station.  Install cross members with white or cellulose glue to allow some ability
to position.  Continue to work forward until F-1 is installed.  Allow the glue to dry, then add the
upper filler F-16, the lower one is easier to install after the fuselage is removed from the board.

Perform a similar operation moving aft on the fuselage from the previously bonded constant
section, making sure to block the fuselage to match the drawing plan view at each cross member
station, until the tail end is joined on the centerline of the drawing.  Allow the adhesive to dry
completely before breaking down the setup.  Remove the blocking holding the tail end together first
and observe if the fuselage springs or twists at all.  If you took your time on the assembly and
worked carefully, the center of the joint should remain exactly where you had it restrained. 
Carefully remove the rest of the support blocking you may have had in place, and remove the
fuselage box from the plan.  Add any remaining cross members that were too troublesome to get to
from the upper side, including the lower F-16 filler at the nose.  Carefully block sand the upper and
lower sides of the fuselage box to level in any cross members that are above the profile of the
fuselage sides.  Sand the tail end of the fuselage square for installation of the filler assembly F-8. 
Detail the edges of the fuselage sides that will contact the stab platform assembly for cleanup, and
check that the two short longerons that the stab platform attaches to are parallel with the top of the
fuselage, and not twisted.

Assemble the stab platform and filler assembly from the 1/32 and 1/8 balsa laser cut part sheets. 
Assemble the filler block separate from the stab platform to start.  Use a piece of scrap balsa
blocking pinned to the building board, and assemble the stack up of 1/8 balsa segments against
this, the aft face being in contact with the blocking to create an even surface.  Use white glue to
assemble, for ease of positioning.  Allow to dry completely before removing from the board.

Assemble the stab platform doubler to the stab platform.  Assemble the bonded filler assembly
flush to the forward edge and sides of the stab platform, leaving a gap of approximately 3/32 wide
to the platform doubler.

Assemble the tail cone filler from the two F-8 parts.  Bond the 1/16 x 1/4 x 5/8 basswood filler to the
top face of this.  Sand the basswood end flush to the block assembly.  Bond this assembly to the
aft edge of the fuselage, making it flush to the top of the stab recess longerons.  Block sand the
filler block assembly sides to carry the taper of the fuselage to an edge 1/16 thick, on the center of
the fuselage as shown in the drawing plan view.  Block sand the bottom of the fuselage and filler
block flush to complete the basic shaping.

Summary of Contents for CBMD-002

Page 1: ...Construction Manual Kit No CBMD 002 www cbmodeldesigns com Copyright CB Model Designs 2008 CB MODEL DESIGNS ...

Page 2: ...the trailing edge segments during assembly The same suggestion applies to the leading edge segment installation as well as both boundaries of the wing will be well controlled dimensionally if this is done When the tip bows are dried remove any blocking near the polyhedral joint to allow access for trim of the bow Use the laser cut leading edge segment end as an angle gauge to mark the cut line for...

Page 3: ...ttle easier to assemble the polyhedral joint and W 1 joint rib Install the inboard panel turbulator spars again allowing for material excess at the dihedral and polyhedral scarf joint locations Carefully remove an outboard panel from the plan Use the outboard joint rib gauge from the laser cut sheet to install the joint rib W 1 against the end of the inboard wing panel still on the board Align car...

Page 4: ...each rib and spar tissue grain in spanwise direction Apply one coat of non tautening nitrate dope thinned 50 after shrinking tissue with alcohol or water mist Horizontal Stabilizer Construction Begin assembly by placing scrap balsa strips along the leading and trailing edge lines of the stabilizer drawing to control the boundary of the leading and trailing edge segments as done for the wing Assemb...

Page 5: ... to the bottom of the horizontal stabilizer Once the fin installation is completed shrink the tissue covering and apply one coat of thinned non tautening nitrate dope to seal At the stab center section apply two additional layers of tissue over the bay that will be in contact with the stab platform on the fuselage to improve mounting stability and allow a strong surface for stab tilt shims applied...

Page 6: ...glue is suggested for fuselage frame assembly Moistening the ends of the 3 32 square and 1 16 x 3 32 members prior to glue application will improve joint strength by allowing the glue to penetrate the end grain Allow the fuselage frames to dry completely before removing from the building board Use a 220 grit sanding block to lightly sand the inboard side of the frames to level any mismatching vert...

Page 7: ...if the fuselage springs or twists at all If you took your time on the assembly and worked carefully the center of the joint should remain exactly where you had it restrained Carefully remove the rest of the support blocking you may have had in place and remove the fuselage box from the plan Add any remaining cross members that were too troublesome to get to from the upper side including the lower ...

Page 8: ...ough the pilot hole and bond together with thin CA Make a mark on the upper edge of segment A for reference to the top of the block Now install the remaining segments using the tube as a guide and best fitting to the laser etched outline of the previously installed segment bonding with thin CA Install segment G with the corner notched The corner piece itself is to be installed into the mating fuse...

Page 9: ...n 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 p...

Page 10: ...mer arm and adjust the tension in the lanyard knot to extend the spring approximately 3 8 to start Observe the timer for movement it should be very slow prior to releasing observe for approximately 25 30 seconds to release from the 12 00 position If it runs faster than this you will need to loosen the knot and lengthen the lanyard slightly to slow down the timer and reduce spring tension If the ti...

Page 11: ...ht Next install the two scrap 3 32 retainer stops on either side of the fuselage Pin prick the tissue in the area these install to improve joint strength prior to bonding In practice the dental band attaches against one retainer stop stretches around the noseblock against the pin heads and onto the opposite stop Finish the noseblock with colored tissue or dust with Design Master floral spray or co...

Page 12: ... evident in the glide start adding shim to the right side of the stab platform to tilt the right stab tip higher than the left until a flat right hand glide pattern is obtained about a 30 foot radius If stab tilt is not quite enough to gain the right hand turn reduce washout in the left wing If this still is not enough add small amounts of right rudder tab until the right turn is satisfactory If n...

Page 13: ...e model in a cardboard box or other storage container Models stored in this manner will look fresh for many months and perform consistently Motor setups If you have never built and flown rubber powered models visit our website to view an article concerning the methods of making motors installing and maintaining them Otherwise some basic recommendations for motors follow 13 grams of 3 16 SuperSport...

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