Thanks everyone!

No . . . I haven't considered putting a motor on it. I like rowing and I built this boat to row! I haven't hit anything yet in many miles of rowing other boats, and I don't really worry about going backwards. I suppose if I built this boat to go fishing, etc, then a very lightweight motor would be reasonable.

The scantlings are: 1.5" gunwales, 1" inwales, 1" chines and keel. All 3/4" thick Western Red Cedar. So far it seem to be stiff enough. Use of other woods may require different sizes unless you want a much heavier boat . . . .
The frames are 1/2" marine plywood.

If anyone wants offsets for RUTH, feel free to PM me.

I considered building a canoe in this fashion, but haven't, yet.

Dave Gentry