The one in the book shows a flat box wrench turned into an offset box wrench
with a spinal bend. And what controlled the curve was a sketch, as I recall
with dimensioned lengths and offset. I never really got the point of why you
wouldn't just use the sketch as the original trajectory of the sweep.
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.