Can't edit sketch pattern

I have come across a number of parts recently that use sketch patterns, that
were created by former colleagues.
I've never used this function before, as I've always tended to use feature
patterns, so that fasteners etc can quickly be added to all the holes with a
component pattern.

Firstly, is there any advantage to using sketch patterns, other than it's
one less item in the feature manager tree?

Secondly, how the hell do you edit them?
If I RMB on a patterned sketch element and pick "edit sketch pattern", I can
change the number of instances, but the spacing value is greyed out in the
feature manager - why?

TIA,
John H

 

Once you create a pattern SolidWorks doesn't concider it fully defined
until you constrain the distance between patterns. This gives you the
ability to create fill scenerios with equal spacing and other spacing
parameters that wouldn't be driven by distance between the first two
entities. (This may be one answer to your firstly question)

 

Thanks for the replies.

It's weird that you have to add dimensions and other constraints to fully
constrain the pattern - it's not consistent with the way Feature and
Component Patterns work.
Anyway, you've solved the problem!

Thanks,
John H

 

All I've ever seen is disadvantages to sketch patterns. One big one is that
sketch patterns are slower to rebuild than feature patterns. Not a big deal
on small, simple patterns, but it can be huge on large or complex patterns.

Jerry Steiger
Tripod Data Systems
"take the garbage out, dear"

 

Thanks for that - I'll definitely stick with feature patterns on anything
modelled from scratch.

John H