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Candyman

Pcd Formula

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Hi all can anyone help with a simple formula to calculate the pcd of a set of holes...

i know how many holes i have and i also know the center distance between the holes

i just need the formula to find what pcd it is..

 

i just wanted a quick way of working out a pcd without drawing it up in mastercam

thanks paul

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Pitch circle diameter

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A PCD is more commonly known as a bolt circle.

 

 

B = D x sin( 360 / (2 x N))

 

where

 

B = distance between bolt holes

D = diameter of bolt circle

N = number of holes in circle

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Just click the bolt circle button in the "create" tab. You just need the radius and number of holes.

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thanks for that but its not what im after.

if i have a part that has say 5 holes in it i can measure between the holes and i know how many hooles there are but i dont know the dia that the holes are on..its this unknown diameter that i want to find..

thanks

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Create a Circle through the center of 3 of the holes?

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From Dave's equation above:

 

D = B / (Sin(360/2N))

 

where

 

D = PCD (diameter you are after)

B = distance between holes

N = number of holes

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Thats it La CAMmer...

Now for another quick question.. how do i put it into a vb script file that i can run?

Thanks

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From Dave's equation above:

 

D = B / (Sin(360/2N))

 

where

 

D = PCD (diameter you are after)

B = distance between holes

N = number of holes

 

The esiest way to find the PCD is :

Find circumference of PCD then divide it by numbers of holes on PCD.

 

For Example :-

(508 X 3.14) / 30 = S

 

where S = center to center linear dist. (not curve wise) between r holes.

 

By this formula u can easily find the degree also.4Stud.gif

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Hi all can anyone help with a simple formula to calculate the pcd of a set of holes...

i know how many holes i have and i also know the center distance between the holes

i just need the formula to find what pcd it is..

 

i just wanted a quick way of working out a pcd without drawing it up in mastercam

thanks paul

 

The esiest way to find the PCD is :

Find circumference of PCD then divide it by numbers of holes on PCD.

 

For Example :-

(508 X 3.14) / 30 = S

 

where S = center to center linear dist. (not curve wise) between r holes.

 

By this formula u can easily find the degree also.4Stud.gif

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A PCD is more commonly known as a bolt circle.

 

 

B = D x sin( 360 / (2 x N))

 

where

 

B = distance between bolt holes

D = diameter of bolt circle

N = number of holes in circle

 

The esiest way to find the PCD is :

Find circumference of PCD then divide it by numbers of holes on PCD.

 

For Example :-

(508 X 3.14) / 30 = S

 

where S = center to center linear dist. (not curve wise) between r holes.

 

By this formula u can easily find the degree also.4Stud.gif

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No math-o-majics needed.

 

1) Create arc end points, using the circle centers as end points.

 

2) Create arc 3 points, using the circle centers as points.

 

3) Create an arc tangent to 3 entities and add the hole rad to that arc value.

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