Here's the latest off my K2..it's a carved top semi-hollow design with the F-hole setup to mimic the grain. I did this by importing a digital picture of the top into Rhino, and then drawing an f-hole shape that jived with the grain patter. The top is black walnut and the back is mahogany...also worth mentioning that I set this up so that the top is angle at 2 degrees to the back surface...to help out with the neck angle.
I might stick it on Ebay...I could use a few bucks for supplies (couldn't we all!) I think this would be a good start for a project guitar for someone.
Here it is on the K2:
Here's a screenshot of the F-Hole design in Rhino:
Here's the finished product, wet down a bit for photo purposes..
The K2 works OK for stuff like this...you just have to keep an eye on it when hogging out a lot of material. Lower RPM's (10,000-15,000) helps out as this ensures that you have adequate torque. I've found that if you try to run this kind of thing at high RPM's, the router runs out of steam. I did the carving with a 1/2" ball mill. I also used the K2 to joint the edges of the walnut before gluing them together.
A couple other tricks...I used 1/4" wooden dowels in addition to double sided tape to fixture the part to the spoilboard. The addition of the 2 dowels does a lot to help the part stick to the table. This way the dowels can absorb all the lateral load from the tool and all the doublestick has to do is overcome the vertical force that is a result of the helix angle on the 4 flute ball mill.