I was working yesterday on tuning up my band saw in preparation for some frame and panel stuff I'll be building soon. I don't have a belt or drum sander and the panels are right on the edge of what is safe to send through my planer. I decided to try leveling them with my freshly sharpened Veritas #4. It worked well, except for actually holding it solid. I tried clamping it in between a dog and my end vise. The panel was so thin (1/4") though, it was tough to get a grip on it. If I tightened it too much, it would flex up in a slight curve.
What's the proper way to hold a thin panel for planing? I thought about a batten clamped across the bench, but it would have to be thinner than the panel.