Golden Era Model Service
High Quality Plan Sets for Radio Control Aircraft
74 inch San Josè
A 1948 design by Antonio Arria

Making a channel for the 1/8 carbon fiber elevator connector.  There are two more clothespins located further out so the elevators
are held straight against the aluminum angle.  A section of 1/16 x 1/4 spruce acts as a guide for the shaft on the ball cutter.



The carbon fiber rod has been installed in the elevators, again using the aluminum angle to keep good alignment including
making sure that the angle of the elevators is the same.  Scrap balsa has been added over the channels and sanded to profile.
 A channel has been cut in the bottom of the stabilizer and the front side is faced with 1/64 ply, setting the gap between the stabilizer
and elevators.  There is no need to make a tight fit if you use a pull pull elevator control system, but for pushrods facing on the
back side of the channel will be required.  On final assembly after covering is applied some 1/64 ply will be set in over the gap.



1/4 balsa blocking has been glued in to accommodate pins at the outboard ends of the elevators.  The elevator and bottom of the stabilizer will be
covered, then these pins will be installed concentric with the arc of the elevator leading edge and the 1/64 ply over the joiner rod will be installed.



Prior to sheeting the leading edge the front of Rib 7 has been sanded to contour with the leading edge and the tip parts have been chamfered to
allow a better gluing area.  The four sections of leading edge were all fitted using three 4 x 36 1/16 balsa sheets.  Fitting them all before any gluing
allows you to make pencil marks from underneath on each end of all the sheets which can be sanded to, not possible if you glue them on as you go.



At this point the inner leading edges are all tack glued with thin CA to the leading edge and the sheeting support stringers at the rear.  
The tip sheeting is glued to Rib 5 and the support stringer, and a little way out from the polyhedral joint on the leading edge.  Using a steel rule a
straight cut has been made in the center of the sheeting.  Perhaps someone can suggest a better method of working with this common
sheeting issue but this one has been found to produce a fairly good result.



Cutting in the tip seam.  The sheet has been glued down all the way to the tip on the leading edge and out to the tip on the support stringer.
 In this photo the aft part of the sheet is overlapped over the front and used as a cutting guide and the sheet is held down on the tip.  Overlapping
the front sheet over the back sheet works a little better.  The saw is razor thin and has very little kerf.  It is called a JLC saw and is from UMMUSA
 on the web.   I find it easier to use in this case than an Exacto knife as it will not follow the grain of the balsa, giving a more accurate cut.



The finished tip.  Gluing of the seam was done from below with thin CA so the top of the sheet would not be hardened.
  The leading edge sheeting has been final glued to all ribs, the leading edge, and the aft support stringer using Titebond III.

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