Okay, guys . . . . . give me a hand with a trig problem:



I'm going to build a small stand. The base will be a tapered cone.
Dimensions are 18 inches high; 8 inches diameter at the top and 12 inches
diameter at the base. I'll glue up 6 tapered boards into a hexagonal cross
section, chuck it into a lathe and turn it smooth.



If this were a uniform column, the boards would join at an angle of 60
degrees. The taper adds an embuggerance. Any suggestions as to how I would
calculate the angles?



I've done this before, but can't remember if I used a trig solution, a
graphic solution or a chart from Lahee's "Field Geology" (true dip vs
apparent dip).



(My copy of Lahee got eaten up by a garage sale along with my g-pick and
brunton before a move a long time ago.)



Suggestions?