Greg's CX4 Project

I have been reviewing the plans and have started detailing the steps for the first task.  The wing spars and center spars are assembled first for the CX4 per Dave Thatcher's instructions.  The spars are assembled using .040 6061-T6 aluminum sheet or "Spar Webs" which are sandwiched between extruded 6061-T6 angle riveted to the top and bottom and steel end spar caps.  I will be posting pictures during the construction phase to document the process further.

Most of my time this evening was spent identifying the materials required.  Aluminum sheet, angles, bar stock and rivets, bolts, nuts and other material.  The price is just around $800.00 for the spars/center spar fabrication and build.  I could purchase pre-made (and professionally built) spars and center spar for $1995.00 + shipping.  That's about $1100.00 more than the raw materials.  Figuring labor at an approximate shop rate of $56/hr (sounds fair, yes?) that means it would take about 20hrs of (professional) labor to produce the spars.  I seriously doubt I will only spend 20hrs to get the same results as the pros.  And this IS probably the most critical part of the CX4 airframe.  The rest of the fuselage is built from the center spar.  And a MAJOR part of the spar/center spar task is getting the dihedral to be exactly 7degrees for each wing spar/center spar mating point.  BUT I am on a limited budget.  So I will try the build it yourself route.

This is getting interesting.

Oh, and here is the way I study the plans and make notes.  Note the nice glass of cabronet sauvignon on the table.  :)