I use a Bosch sander http://www.boschtools.com/Products/Tools/Pages/BoschProductDetail.aspx?pid=ROS65VC-5 and a shop vac with a dust deputy cyclone between the sander and the shop vac. http://www.oneida-air.com/category.asp?Id=%7BCC6B6F2A-E3D7-4F18-A53C-B5C357DFE131%7D

With a kayak, you also have the consideration that you are frequently sanding on a curve, so less of the dust is able to make it through those little ports on the bottom of the sanding pad without a vacuum source.

If you are really interested in eliminating dust, you should also consider Abranet abrasives. They are an abrasive mesh and are made specifically to increase dust collection efficiency. I have used them in the past, particularly when sanding curves, because they really do make sanders virtually dust free, but they do not last as long as standard paper-backed abrasives, so unless I need the added dust collection capability I just use paper. http://mirka-online.com/catalogsearch/result/index/?cat=1256&q=abranet&gclid=Cj0KEQjwjrqvBRD6wf2fy-C61PIBEiQAUzKQTocHZYB7NanxUEs4vB4YXRBG-9Vf1DGlWA7gR7ydYAsaAjh08P8HAQ

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