Image may be NSFW.
Clik here to view.
I have a curve, as shown in the picture above, along which I want to pattern some fixing holes.
The patterned holes must line up with matching holes in the part to which this part is fixed.
The obvious way to go (it seems to me) is to create a point on the curve, a distance from the end of the curve, and build the hole feature on that point, then pattern the lot along the curve.
Now here's the difficulty:
I want my holes to be neatly arranged - either the 1st hole should be the same distance from the end of the curve as the last hole is from the other end, or the whole lot should be symmetrical about the mid-point of the curve. (I know they are basically the same, but they are meant to indicate different ways of achieving the same thing. Bear with me...)
I do not have control over the total length of the curve. It will be some weird overall length, like 763.972mm.
I want to have a dimension to show on the drawing that defines the pitch between holes, in terms of distance along the curve - something like '9 holes on 90 pitch'. I am therefore precluded from using the 'Ratio' placement of the point on the curve.
If I start at one end of the curve and pattern the holes along it, I end up playing with the start and pitch dimensions repeatedly until I am happy with the arrangement
The neatest way I have found to achieve this is to create 2 separate patterns of holes, one at the mid-point of the curve and patterned in direction 1, the other starting at one pitch away from the mid-point and patterned in direction 2. Thus, I end up with what I want, BUT there are 2 patterns. I would prefer a single pattern.
How do you do it?
I suppose one answer is that, if I did the one-sided pattern and lived with the untidy hole placement, it would make my part Poka-Yoke! But that is another consideration altogether.
I am sure there is someone out there who has a clever way to solve my predicament. The answer is quite likely staring me in the face!
I am interested to hear your ideas.
Cheers,
John
