"Triangular" Shape Hole Cut Pattern

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


Thanks in advance for any info.

regards,
Chris

 

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.

 

: 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