Default Sketch Coordinate Systems

[melmo]

Is there a way to set Inventor so that the sketch origin defaults to the part origin?  I find it very frustrating that it always defaults to some random corner of the part's body.  It can screw up a part if you decide later on to modify the part such that you eliminate the point to which a coordinate system was defined.  Also, when copying and pasting a sketch to new work planes it can be a pain to figure out which point is the origin of the orignal sketch if the pasted sketch is misaligned. 

I know you can edit the coordinate system after a sketch is created, but I'd prefer not to have to rememember to do that with every sketch.

This was brought up about 6 years ago and there was no formal resolution

http://forums.autodesk.com/t5/Autodesk-Inventor/Sketch-defaults-to-some-random-edge/m-p/1279242/high...

In the second-to-last post John-IV8SP1mentions an option under 'Application Options' for an older version of AI, but I cannot find it in the 2012 applicaton options.

[swalton]

No.  You can't control the origin or directions of the sketch coordinate system while making a sketch.

You can do so after making the sketch.

Steps:

create a sketch on any surface

exit the sketch before creating any geomety

RMB on the sketch in the browser, select edit coordinate system

click on the ball at the center of the x-y pair that apears, then click on the point that you want to be to origin.

click on one of the axis of the x-y pair, then select a line, edge, or axis that is in the correct direction. 

RMB again and select flip axis if required and then done.

edit the sketch to start creating the geometery you need.

This workaround annoys me, so I just accecpt the IV provided system.

ProE allows you to override the automatic sketch coordinate system during creation.  In that program, I make the kind of adjustments that you want.

[JimW]

Thanks, SWalton.

I've been doing that critical instances. Other times I project the model planes or axis into the sketch and work from there.

Still, it's annoying since I came from SW where it is standard.

[JimSteinmeyer]

Scott,

We are talking about two different things. I already have a template set where the FIRST sketch is centered on the center point so we always start where we want. I think that is what you are suggesting.

The annoyance comes when you go to make later sketches and Inventor creates a sketch coordinate system with the center point at some corner of the currently existing geometry. It seems to select the lowest left point available. As we design based off the universal center point this is only an annoyance moste of the time. However if the part is redesigned at a later date to where the cornor Inventor selected is removed the sketch fails.

[JimW]

Jim,

That is precisely why I have called it a fundamental flaw. All sketches in a model should originate from a point that is not going to be affected by subsequent changes to the model. So much back tracking and fixing and wasted time could be avoided if this was basic to the program.

[melmo]

SWalton,

First of all, thank you for actually reading my question, understanding what I'm lasking, and giving a succint answer, even if it's not the one I was hoping for.  It is refreshing to see an answer from someone on these forums that is neither snarky nor an attempt to put down a user for pointing out somehting they find frustrating in Inventor.

As far as your instructions, it is worth pointing out that in IV 2012, as long as the sketch has not been consumed in a feature, you can eidt the coordinate system from within the sketch by clicking on the pull-down menu in the 'Constrain' group of the 'Sketch' tab on the ribbon.

[JimSteinmeyer]

Melmo,

So this reconstraining is available within the sketch mode? The way I read Swalton's reply was that we had to exit the sketch, reconstrain it, and then edit the sketch. If it can be done within the sketch mode it could be acceptable.

Thank you

Jim

[swalton]

My workflow is how I have done this since starting with IV 10.  I did not know about the option to edit the sketch coordinate system from within the sketch environment.  Thanks for pointing it out.

[melmo]

Jim,

I was actually only partially correct.  I said you can modify it from within the sketch as long as you haven't consumed the sketch in a feature.  I should have said that you can modify the sketch coordinates from within the sketch (pull-down in 'Constrain' group), provided that you have not done anything downstream, whether that be a feature that consumes the sketch OR created a new sketch. Otherwise you will have to exit the sketch and proceed as SWalton described.

It is still an issue to me that it is not automatic, for if you forget to edit the coordinate system and then try to later, you could screw up your part as I literally just did..

[Cadmanto]

JIm,

I hear what you are saying.  I guess I will have to take more notice of this.

A lot of the parts I have created are all based on the center.  I can see where this would be an issue.

I know in Solidworks we would just create a new csys.  While I have not had to do this yet in Inventor,

I am sure a similar command exists.  And that is probably what needs to be donein this situation.

[JDMather]

---

@Cadmanto wrote:

I know in Solidworks we would just create a new csys.  While I have not had to do this yet in Inventor,

---

I have been using SWx since v2001 and Inventor since v7.  Never spent a millisecond worrying about coordinate system.

If a sketch goes sick becuase of edit of parent feature -  I simply fix it.
If a copied sketch is not oriented as desired I simply convert it to a sketch block and oreint as needed.