"Triangular" Shape Hole Cut Pattern

Have you tried a Fill Pattern? I've seen 'em, but never used 'em. Think they're more or less intended for such things....?

The fill pattern should work, you need to create a datum curve the shape of your triangular outline. Then place the one hole and use the pattern fill comand. You'll probaly need to play with it a couple of times.

Thanks for the reply . what confuse me is I had seen this feature but it just a single pattern without any datum curve.

: "Chris Blade" wrote : Hi , : : Anybody had created a triangular shape of pattern before ?. What I mean is : the cutting hole on a solid body align to be triangular shape, from 1 in 1st : row, 3 in 2nd row, 5 in 3rd row, 7 in 4th row and etch . : It should be created using pattern relation which I dont know how. : : O : OOO : OOOOO : OOOOOOO : :

There is a somewhat simple beginning to this this row relationship: each successive row is offset fronm the preceeding row by one and, in total length is two short of the preceding row. Seems like a fairly simple algebraic relationship.

The only thing that is missing is the parameter for a pattern. These you will find by selecting the pattern, going to the Info menu and selecting 'Switch Dimensions' which will show you the symbolic, variable name for the pattern parameter.

Strart with the following pattern: First direction: * Pick the X dimension, set pattern increment and number of instances

Second direction: * Pick the Y dimension, set pattern increment and number of rows * Again pick X-dimension value and specify offset from x (one, in this case because entire row is two less than previous.)

This will give you a pattern that is parallogram shaped. The relations you asked about cause the pattern increment parameter, p15, or whatever the actual symbolic value is, to vary by two less for each row (beginning offset by one, length of pattern {that is, the initial pattern length of 7, will be two less for each row until one is exceeded} is 2 less.)

It may be necessary to do this with Pro/PROGRAM and relations within it. With it you can use conditional expressions, such as IF P15=2 THEN P14=5 IF P15=3 THEN P14=3 IF P15=4 THEN P14=1

Each time the pattern is evaluated by pattern increment, p14 and p15 (pattern increment values) will be evaluated for their values and compared with the conditional expression.

There is an entirely different method of shortenting the pattern to give a triangular shape based on converting a dimesional pattern to a pattern table. The pattern table can then be edited to comment out the number of instances at the end of each line to produce that triangular shape (2 in the second line, 4 in the third line, 6 in the fourth line.)

David Janes