How do I create a non-parametric sketch / change sketch transform?

[matt]

I'd like to change the transform of a sketch, but 'isParametric' is always true for any sketch I create.  How do I either set isParametric false, or create a sketch that's not 'parametric' to begin with?

[p.seem]

As far as I can tell, isParametric isn't something you can control at the sketch level.

If the design itself is parametric, any sketch created in the design will be parametric.  If the design isn't, neither will any of its sketches.   If you change the design from one to the other, the sketches will be 'downgraded' but not upgraded.  That is, if you switch the model from parametric to not, all the sketches get 'downgraded' to not parametric.  If you switch the design from not parametric to parametric, the sketches stay not parametric.

For what it's worth, you can set whether the design itself is parametric through the api, as detailed in AutoDesk's blog, here. 

Hope that helps.

[matt]

Thanks for the reply.

I figured out that I can create nonparametric sketch in a base object, but unfortunately, that's not going to cut it.

What I really want is to control the transform for a fully parametric sketch.   I understand that the transform is linked to whatever underlying object was used to create the sketch, but Fusion's choice of orientation seems arbitrary and often unintuitive.

When doing ordinary modeling, this is occasionally a problem, but generally it's not too tough to work around it. 

In the scripting scenario it comes up much more often.  In my present case, I'm having to basically work in 'world' units on every sketch, mapping to sketch units as a last step before creating my geometry... a major PITA that makes my code difficult to read.  The ability to tweak the sketch transform would be a very welcome addition.

Any plans to implement it?

[BrianEkins]

I don't think there are plans to support setting an arbitrary transform for a sketch.  Here are a couple of thoughts though.  The first is if you create a sketch on the model X-Y plane, the sketches coordinate system will align with the world coordinate system so there's no need to do any adjustment from world to sketch space.

Another alternative is to create a new component and create a sketch on the X-Y plane of that component.  You can now draw geometry in that sketch and then if you need to transform it relative to the world coordinate system of the root component you can transform the occurrence.  This is also a good option if you need more than one instance of the sketch because you can create multiple occurrences referencing the component and its sketch.