So this afternoon I set up the sawhorses, laid out the ply, and grabbed the camera, so I could do a "by the numbers" post on how to scarf plywood, not the easiest way to join plywood, but probably the best. Of course, what I didn't realize was that the batteries in the camera were dead! So no pictures, but here's how I did it:
1) Stack your plywood flat on top of a flat surface (I used 3/4" plywood).
2) Your scarf should be 8 times longer than your thickness, so I staggered the ends of the plywood at 2 inch intervals (1/4"x8=2").
3) Screwed it all together so it wouldn't move on me.
4) I started with the planer, running it along the edges of the ply until it was almost feathered into each other.
5) Finished up with the belt sander, so I ended up with one smooth angle.
6) Turned it over and did the other end.
And voila! You can't see it, but now I have scarfs to make the joints in my hull nice and smooth! I was so happy with the results, I glued my first joint tonight. Remember to put down plastic wrap under the joint you're glueing, so you don't glue your ply to your flat surface!
It's good to be working again. I really have to thank my i550 friends for keeping me motivated, and the http://i550class.org/ site for all sorts of information!