I came across an interesting link with various D-28 soundboard, side and back thicknesses from different years of production: http://www2s.biglobe.ne.jp/~somemura/itaatsu.htm

Post #5 - Rosette

Hopefully, I'll have time to layout the rosette dimensions and template on the soundboard tonight. Here's another shot of the D-45 style rosette:

Update: I measured the individual rosette purfling pieces.  First, the soundhole has a 4" diameter.  From the soundhole edge to the first (inner) ring is a gap of approx. 0.115."  The  inner and outer rings comprise B-W-B-W-B purfling of approx 0.087" width.  The gap between the center ring and the outer rings is approx 0.125."  The center ring comprises B-W-B-W'-B'-Pearl-B'-W'-B-W-B purflig of approx. 0.316" width.  The B' and W' segments are thicker than the other B and W segments.  The pearl segment is approx 0.069".

Post #4 - Prepping for inlaying top and backs

I had already jointed and joined the top and back when we were still back in Tahoe (circa 2000).  They just needed to be thicknessed.  The top was thicknessed to 0.12" and the back 0.11" 

Here are the pieces ready for the rosette. I'll be employing a rosette similar to the D-41 and D-42 (BWBWB-BWBWB|ABALONE PEARL|BWBWB-BWBWB):

The back will have the HD-style (zig-zag) strip:

Here is my home-made (fiberglass) rosette cutting jig and the stew-mac dremmel jig.

and mounted to the dremmel:

Now I need to go find my routing bits...

Post #3 - Side Bending

Time to bend the sides and begin forming the rims. First step was to soak the sides in warm water for about an hour.

Here is the bending iron clamped to the workbench.  

I started with the upper bought, then the waist then the lower bought.  There are a few good videos on Youtube showing the process.

Half way there:

What takes most luthiers about 15 minutes took me an hour or so, but overall I'm happy with the result.  Time to let the wood dry for a day or so.  It will be another week before I have time anyway.

Post#2

While waiting for some parts (glue, cement, adhesives, etc.) to arrive from stew-mac, it was time to cut and put together the spreaders for my dreadnought guitar form.  Glue is still drying, and I'll finish off with a flush cutting bit on the router.

The other build was to put together a side bending iron from some parts from home depot.  I generally followed the suggestions from this link, and made some modifications to make it fully enclosed with the pipe mounted directly to the enclosure.  The finished iron is shown below.

Guitar Building Projects

Post #1: Start of D-41 Study underway.  

This is going to be a long term build due to my limited time.  The first goal was to set up the Ryobi drum sander and get it leveled. The sides are now thicknessed to 0.085"... ready for bending.