Hi Stephan, this is the way I look at it. Most of us don't have the perfect tools and, wood does not really want to be machined perfectly anyway. In your situation, I would probably try switching the grain orientation to see if it changed things. Then I would pass it across a jointer plane I have mounted on some sawhorses (see http://www.chipSandresky.com/cedarstrip/images/horses.jpg ). That would even out any irregularities. The pieces are small enough so it's not such a big job. You could rent a table saw for $40 but even then, unless the blade angle is perfectly aligned, you will have irregularities. Wood is just that way

I hope this helps,
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