On 4 Oct 2005 07:28:48 -0700, wrote:

Thanks again, that has my projects rolling.

Alot of the programs, BOLTCIRC & the latest one that Micheal Allard
brought to attention are wonderful if the bolt circle radius is known,
but unless I am missing something critical here, when you only have the
center to center dimensions for the layout, then you are back to doing
the math by hand, or using an AUTOCAD type program. Is that statement
correct? thanks again all, ron


The center-to-center distance is referred to as the 'chord'. If that's known,
then calculate the 'angle' between adjacent bolt holes as:

angle = 360 / (number of bolt holes)

Then the bolt circle radius is given by:

radius=0.5*chord/sin(0.5*angle)

Regards, Marv

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