Cabinet scrapers work great. Although in my experience you will be the only one who really notices runs. I used to literally lose sleep over minor imperfections in my kayak, but after a few years use my boat has proven stronger and more useful than I ever expected. The only real problem I have is that like so many other first time builders I overbuilt, and I do wish my boat was lighter.

: First of all, join the club! If you let it get pretty hard you can
: use a cabinet scraper to reduce them and level them off. Curved
: scrapers are available from Woodcraft and other woodworking
: supply places.

:
: http://www.amazon.com/Crown-376-Cabinet-Scraper-Gooseneck/dp/B001C06BLE/ref=sr_1_2?s=hi&ie=UTF8&qid=1345740718&sr=1-2&keywords=card+scraper