pc software for bolthole layout?

DesignCad or almost any CAD program will do that for you. For real accuracy you need to rotate the bolt circle under the drill press or mill with a dividing head. Bugs

Hey D-B,

I note he has recently moved his site to here. Surprised he didn't drop in and tell us.

Lot's of good stuff, and it's freeware.

Take care.

Brian Lawson, Bothwell, Ontario.

I considered it but decided that the subject wasn't sufficiently political for RCM. :-)

The BOLTCIRC program won't produce a paper pattern but it will generate the (x,y) coordinates for the holes which, IMO, is more accurate than a pattern.

I recently had occasion to lay out holes of varying diameter on a bolt circle such that the hole-to-hole spacing was constant. Solving that problem involves iterating a transcendental equation which is a bit messy to do by hand. A new program, VREV, does the dirty work.

Regards, Marv

Home Shop Freeware - Tools for People Who Build Things

Hard to tell how much accuracy you ned, but your printer will provide a representation of what you want, but won't be very precise