The orbital has a orbital motion - little circles. The random orbital has little circles inside bigger ones. The random orbital is a lot smoother on finer grits, and more powerful removal on the heavier grits. Highly favored. I have an old Makita that has eaten several pad bearings but it keeps going, and going... Look at DeWalt and Porter Cable, they are the top two. Common shop vac attachment very handy. Wood magazine recently reviewed them, and said that variable speed is not a necessity but is nice.

> I am looking into buying an electric sander. What is the difference
> between an orbital sander (square base with clips to hold sandpaper) and a
> random orbital sander (circular base with adhesive holding the sandpaper).
> Which is more appropriate for sanding my kit kayak? Thanks