for cutting strait pieces of wood, wheather with the grain or not, I like using the typical utility knife http://en.wikipedia.org/wiki/Stanley_knife its way stronger than a exacto knife, the blade doesn't flex, and provides clean strait edges for glueing sheeting together.</p>

when I an trueing the edges to glue sheeting together( for wings as a example) I use a metal strait edge clamped to my building board edge and a utility knife.</p>

the utilility knife has a handle thats so much easyier to grip, cutting through thicker wood is a snap.</p>

of course I also use a regular Exacto knife where curved cuts are needed or where a quick slice here or there is all I want to do, and a razor saw where larger wood, like spars, or harder wood like ply or birch requires a strait clean cut.</p>

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