heya; you can limit the amount of bend by setting the min/max for the rotation dials. for example, if you want, say, a bear trap jaw to only rotate between 0 and 45 degrees on the x axis, double click it's xrot dial, and enter 0 and 45 as the min and max. you can also double click the y and z and set the min/max to zero to prevent bending on those axes. for the parts that move, but don't 'bend' (that is, you dont want the mesh to deform), hit ctrl-i and uncheck the body part's bend box.