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hca question

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fire&ice

Ideal_Rock
Joined
Jul 22, 2002
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7,828
..been playing w/ the HCA - plugging in different numbers. I understand that angles are more accurate - but for the sake of argument - I'm using %

When I use the same crown % & pav. % and adjust the table & depth - the results are much better for smaller tables (57-58%) - the results are better w/ depth of 60%.

Why is that and what is the relationship to the crown/pav% & the table & depth.
 

fire&ice

Ideal_Rock
Joined
Jul 22, 2002
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7,828
..still confused.

I plug in the same pav, depth & crown %
take the table from 59% to 58%

score of the 59% - 2.4
Score of the 58% - 1.7

Does the table make that much difference?

O.K. reread your tutorial - so those relationships have the most effect on Brilliance?

Will the look be significantly different?
 

pricescope

Ideal_Rock
Joined
Dec 31, 1999
Messages
8,266
HI F&I, It is easy. :)

Firstly, HCA penalizes large tables size when it over 58% and 60%.

Secondly, HCA is based on the angles. When you enter %, the program calculates the angles based on simple trigonometric formulas.

Table size is used to calculate crown angle from crown height %. Therefore, when you change the table size with constant crown height you're getting a different crown angle!

Similar to table-crown relationship, accuracy of the culet size will also affect the final result when you’re using pavilion depth %.
 
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