Experimental Aircraft Models
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WWW.RCHomebuilts.com
5) You will be sliding the channel into the opening in the
firewall and bonding it in place. To fit, you will need to cut
the height of the ‘legs’. Position the channel up to the
opening in the firewall with the bottom resting on the bottom
of the opening. Mark the legs and cut the channel to fit.
(You may want to square up the upper edges of the
opening.)
6) Slide the trimmed
channel into place to test
fit. It should touch the
back edge of the NACA inlet and sit on the bottom of the
opening in the firewall. While in place, score a mark along
the bottom of the channel flush with the outer edge of the
firewall (This will help you determine where to apply the
adhesive and you’ll trim off the excess after it’s bonded.)
7) Remove the piece. Apply Medium CA parallel to, and inside, the scored line you made so
that it will bond to the firewall plywood.
Position the duct in place and hold in position until
the CA sets.
Turn the fuselage over and apply some thin CA to
flow into the joint between the bottom of the duct
and the fuselage.
Mix up a little epoxy and dab into the seam
between the duct and the NACA vent to support
the front edge.
8) Trim the excess length flush with the firewall
9) Repeat for the remaining two inlets.
Reinforcing the Bond of the Interior Frames
The bonding of the interior frames needs reinforcement. While we
increased the contact area with large balsa triangular ‘gussets’, we still
recommend reinforcing the bulkhead to fuselage joints with epoxy/glass
cloth. We have included two yards of glass cloth tape, an application
brush and filler material with your kit. You’ll need about 4 oz of 30 minute
epoxy, rubbing alcohol and a mixing stick to complete this reinforcement.
Read the bulleted items below first and then use
the accompanying pictures:
The most important frames/bulkheads to
reinforce are the nose wheel bulkhead
and the bulkhead over the rear landing
gear mount.
Scuff sand the areas of fiberglass next to
the frames where you’ll be bonding the
fiberglass tape into place.
