|Currently I have most of the fittings for the wings
made. The spars have been purchased but the holes for the various fittings
aren't drilled. I have purchased one pair of wing ribs with one pictured above.
I will be making my own wing ribs but all the details are not shown on the
plans, so I needed something to take some measurements from. I would have been
disappointed with the quality of the ribs if I had purchased a complete set. I
will be making 4 aluminum form blocks, 2 for the left and right ribs and 2 for
the left and right aileron ribs.
The airfoil used is a modified Gottingen 387. As near as I
can tell, the modification is making the bottom side of the airfoil flat. I got
the coordinates for the airfoil from a book at the Wichita State University
Library. I used the coordinates to draw the airfoil full scale in Unigraphics,
the CAD system we use at work. I plotted the airfoil full size and used the
ribs I purchased laid on top of the plot to tweak my airfoil drawing to a close
I have a solid model of the form blocks drawn in Unigraphics
and I will be machining the form blocks on my CNC equipment. The rib flat
patterns will be cut on my CNC router. The material I will be using is 2024-O.
The ribs will be heat treated to the T42 condition.
I am working on an article detailing the processes I have
described above. It should be finished in the next week or so. You can also
take a look at the equipment used by following the link below.