I'm a woodworker and I'm building a stitching pony (I'm starting leather working).  I'm looking for advice about a couple design features.  How big of a clamping surface is recommended?  Should I add a piece of leather to the clamping surface? I'll be adding a pair of magnets near the top.  I think a needle will find a natural alignment on the magnet.  Before I glue the magnet in I want to align it so the needle is in a convenient position.  Is there a preferred alignment such as angle