Bike project 1: Still working on the seat

It seems like the seat should be a relatively simple thing.  Not so.  As the design has progressed the seat issue has become rather central.  First, a bit of measuring of several other recumbents based photos shows that the seat height should be somewhere in the 20" range to allow a seated rider to reach the ground.  It turns out that this has a significant impact on the overall design including the wheelbase. 

While working on the seat issue I've encountered some considerable difficulty with the front wheel assembly.  It turns out that my initial sketchup model has an error so that the component center line was not aligned with either the wheel or the steering head.  Not good.  So I've had to go and redo the front wheel assembly.  Here's what it looks like now:

In the process I've become rather better at placing components in sketchup.  It's really an interesting and useful 3D surface modeling system.

In the process of working on the seat I ran into some difficulty with curves.  Sketchup's standard curve tools are a bit limited.  A bit of searching, however, lead to SketchUcation.  This is a great sketchup site with, among other things, a package of Bezier extensions for sketchup.  You need to join to access them but it's free and the site really seems to have much to offer including many advanced training videos. 

At any event here's the new seat:

With both the revised front wheel and seat in hand I can return to the frame.