# Bolt pattern



## richard.nott (Aug 15, 2014)

wanting to make a plate for a dividing head and would appreciate a formula to figure the diameter of the hole pattern. dimensions known holes 127, hole size .125", distance between holes .0625". thanks for the help Richard


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## Tony Wells (Aug 15, 2014)

Richard, couple of things here. First is the spacing. You say 0.0625 between holes.....you mean edge to edge? Obviously, center to center won't work, as they would result in a parting of the plate. And is the 0.0625 straight line or arc length?


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## wawoodman (Aug 15, 2014)

If you are using a DRO, here's a handy calculator

http://www.doov.com/cgi-bin/bolthole.cgi

EDIT: Sorry, I misread your post. This isn't what you want...


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## Cobra (Aug 15, 2014)

Circumference would be 127 times 0.125 plus 126 time 0.0625. 
Diameter you divide your circumference by pi.


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## emasbury (Aug 15, 2014)

richard.nott said:


> wanting to make a plate for a dividing head and would appreciate a formula to figure the diameter of the hole pattern. dimensions known holes 127, hole size .125", distance between holes .0625". thanks for the help Richard



Try this and see if it works.
Ed

http://littlemachineshop.com/mobile/bolt_circle_dia.php

They have several different calculators. hope one of them will work.

Ed

http://littlemachineshop.com/mobile/menu.php


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## videotrack (Aug 15, 2014)

Ed, that's a great web site. Thanks for sharing.
Trevor


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