Circular pattern - second direction

brian_brady

We can use two directions for rectangular patterns, but I don't see that we can use a second direction for circular patterns. Is this possible in the single tool, or will I have to make a linear pattern first and then use that to make the circular pattern. Picture the holes in a shower head as an example.

mahir

Yeah... no Whether you want a radial pattern direction or a second angular direction, the built-in circular pattern feature doesn't do that. A FeatureScript could be written to do this, though. Time permitting, I may give it a go.

daniel_splawski

Are you talking about a radial offset or a pattern that migrates both in the clockwise and counter-clockwise direction?  I'm very interested in the latter.  

mahir

Yeah... no Whether you want a radial pattern direction or a second angular direction, the built-in circular pattern feature doesn't do that. A FeatureScript could be written to do this, though. Time permitting, I may give it a go.

viru

@brian_brady, Currently this facility is not available in Onshape. You can raise improvement request for this. In near future we hope that this facility will be provided by Onshape like other CAD tool.

mahir

@brian_brady, I think I've created what you're looking for.

FeatureScript Radial Pattern

brian_brady

mahir said:

@brian_brady, I think I've created what you're looking for.

FeatureScript Radial Pattern

Maybe, but it does not work for an extruded hole in a simple round plate. It will not create the pattern even without the second direction. I tried using the outer, round surface of the plate for the axis. No go. Then I added a sketched centerline before I tried making the pattern and used it as the axis of revolution. No go again.

I prefer this type of functionality to be built into OS, not just via scripts.

mahir

You don't always get what you want when you want it. In the meantime, FeatureScript fills the hole.

I'm not sure how exactly you're trying to pattern that hole, but take a look at the example tab in my document. There is specifically a pattern of holes going through a plate, along with other examples. That being said, I don't see why your pattern shouldn't work if applied properly. Most of the code was copied from Onshape's own circularPattern and LinearPattern feature and has the same options/flexibility. Don't forget to select a Seed Point so the feature knows what direction is radial. Also, be sure you've selected the right type of pattern (part, face, or feature). 

ilya_baran

@brian_brady
A big part of the point of FeatureScript is that it is exactly how we build the built-in features ourselves.  For example, here's what the code to our own circular pattern looks like: https://cad.onshape.com/documents/12312312345abcabcabcdeff/v/2de19ab793fd2712770de4d1/e/5e639eb1b1834188ae46203a
At a very high level, it's pretty similar to Mahir's code.
Of course, we have stringent processes for QA, documentation, etc., but it's not like other CAD systems where scripting is the ugly step-child -- in Onshape a user-built custom feature can easily be as good as one of ours.

mahir

@brian_brady, here's a link to another example with holes going through a plate using the cylindrical surface as an axis. I would review how you're trying to apply the pattern. It's probably something minor like an errant click on the wrong geometry.

https://cad.onshape.com/documents/57acdfaae4b005c413ed9b6f/w/3fd585a46d3af1b3ba413c53/e/b36406b232aa470add7fdbc0

brian_brady

mahir said:

You don't always get what you want when you want it. In the meantime, FeatureScript fills the hole.

I'm not sure how exactly you're trying to pattern that hole, but take a look at the example tab in my document. There is specifically a pattern of holes going through a plate, along with other examples. That being said, I don't see why your pattern shouldn't work if applied properly. Most of the code was copied from Onshape's own circularPattern and LinearPattern feature and has the same options/flexibility. Don't forget to select a Seed Point so the feature knows what direction is radial. Also, be sure you've selected the right type of pattern (part, face, or feature). 

I figured it out. The built-in circular pattern tool has Equally Spaced checked by default and your FS does not. Once I checked the box it worked. I would recommend either checking it by default or not having 360˚ be the default angle. Thanks for making this.

mahir

I edited the FS so you can select which instance of your pattern corresponds to the seed location. The seed location is limited to between 1 and the instance count minus 1, i.e. if you want to make your seed the last entry in the pattern, just flip the pattern direction instead.

https://cad.onshape.com/documents/57b7740ce4b002b1d76d73b8/w/74ebb8e6fc5c218c0891f528/e/996c6eca6596bcc05033e846