Turret mills; Quick vertical part holder.

[Toolmaker51]

Today I had some endwork to perform...too long to rest on table with vee block kind of low from surface to be done. Our horizontal is tied up with a longer running job, and I don't like swiveling the turret type past 45 unless imperative.
Hmmmm....The bulk of turret mills, and many others have a small scale tee slot on front of the X axis bed. So a handful of salvage material, some bandsawing [of course, whats a creative project with out a bandsaw portion?], this was the solution. Vee clamps on a 3'' dia. Made long tee-nuts to engage more slot for strength. You can reference http://www.homemadetools.net/forum/double-t-nut-46086 for considerations on double tapped tee nuts.
This not a very rigid clamp. This was just center drilling plugged tubing for a lathe job, instead of mounting steady rest and workout pushing tailstock to and fro. With the ram swiveled to dial the diameter in, went quick enough, and tooling to save for the future..
Properly designed and executed there would be tapered legs, tabs for perpendicularity from top surface, broader feet, webbed/ gusseted corners, an arch for the threaded clamp bolt and more thickness to the vee's narrow section. That vee is not correct either, profile too wide for diameter available within the frame.
But you still would have to be careful when tightening mounts and part.