Thanks for all the replies.  Keep them coming!  Also, if you, each of you,
have not looked at the album, the link for which I posted initially, please
do so.

First, the design, such as it is, is influenced by two principal sources.  
One are the hurdy gurdys of Michael Huppert in northern California,
Mendocino county, where I am from.  

Two, there is an old drawing in Doreen Muskett's book that shows a similar
bracing design and as a lute maker I realized that the wheel and bearings
should be stoutly braced so as to stand up to vigorous playing.  The
bearings are set in ebony floating surrounds and epoxied in place in a
refractory fashion after the mechanism was well established.  Wood expands
and contracts and is subject to hygroscopic changes that I wished to
control.  I will make the next one differently by using a material with a
higher modulus.  The braces I used are quarter sawn old heart western Red
cedar I milled myself.  500 year old wood.  Thinner pieces of Larch or
Douglas fir or simple Sitka spruce would be better.A lute bowel needs to be
very light...almost a "hot air balloon" really and that is simply too light
a construction for a mechanical device or engine, if you will.  

About the entrapped compression springs...the design is very simple with
few and readily made parts.  Each key shaft is milled and then the
cylindrical section is lathe-turned.  They will not wear out for any
foreseeable time.  Now the issue of finger fatigue may be a concern but as
I can play a guitar, zook and even a bass for six-eight straight hours and
survive I wonder how that will be.  Since I am not a "gurdyest" I can only
take your words for it!  The centers for the turned ends of the key shafts
will serve as pilot holes for screw attachment of a wooden washer or keeper
and the weight of the action is quite adjustable.  I have repaired a few
Clavichords  which have an action that depends more on the spring action of
the strings rather than any gravity or other weighted return.  Since I
figured that I'd play this baby on my lap sometimes that these spring
return action would be a good idea.  I will put up further photos as I
continue this project.

One thing I will be doing is casting a bronze crank for the instrument
which should be fun.  I try to stay away from metal pieces in my
instruments if I can, and tailpieces and bridges are always wood, dense
wood to be sure but wood none the less, but I think a beautiful bronze
crank would not be too far out of line, no?

Thank you all.  More ideas are welcome.

Dave Bucher
The Golden Wood Stringed Musical Instruments.