Paul - The scrapers seem to work best on 'green' epoxy. As the resin gets harder,you may find sanding easier than scraping.

I am in the process of building a Coho. I was outside sanding with my trusty Craftsman 1/4 sheet sander when my neighbor came over on an inspection visit. After watching me for a minute, he came back with a Makita ROS. The Makita sands at a rate 3 -4 times that of the Craftsman, and is a pleasure to use. The hook and loop sandpaper is also a blessing, since the epoxy seems to dull paper at a phenomenal rate. After a brief use, I ordered a Makita from Harbor Freight Tools for about $55. Seemed like a good deal, and the ROS so outperforms the Craftsman that I haven't had any second thoughts. I have also noted that the numb feeling you get in your hands after using a 1/4 sheet for awhile is less intense with the ROS. All in all, I strongly suggest a ROS. Just buy lots of disks with the machine, because they chew them up pretty quickly. Good luck on the Tern!