I work for a custom stair builder and often find myself working on small or odd shaped pieces such as handrail fittings. Unfortunately, I have a hard time holding them for sanding or shaping, and the boss won’t spring for a bench vise. To make do, I’ve found that I can substitute a large handscrew for the job. I clamp my workpiece in it, and then secure the handscrew to the bench with a couple of F-style clamps. The setup actually works pretty well. Even clamped down, the handscrew can still be adjusted enough to allow repositioning of the workpiece without a lot of hassle.