Symmetric constraint?

james_mcpherson11762

Am I missing the symmetric constraint? It's one of my most used constraints in Alibre. Currently I just dimension everything to get symmetry, but when I change a dimension that causes 4 times the work compared to when I use symmetry. If it truly isn't there (yet), any tricks on quick work arounds?

-Jim

jakeramsley

Best workaround I can come up with is to use the sketch mirror to create the symmetric geometry.  At this point, they will have a mirror constraint which will keep them symmetric.

Another option would be to use a construction line to one piece of geometry, mirror it, and then attach it to the geometry you want symmetric.  The mirror line will be mirrored and constrained to your geometry letting the positions be symmetric.

james_mcpherson11762

jramlsey said:

Best workaround I can come up with is to use the sketch mirror to create the symmetric geometry.  At this point, they will have a mirror constraint which will keep them symmetric.

Another option would be to use a construction line to one piece of geometry, mirror it, and then attach it to the geometry you want symmetric.  The mirror line will be mirrored and constrained to your geometry letting the positions be symmetric.

Great tips, thanks. I'll give those a shot.

3dcad

I'm missing symmetric constraint also. It makes mirroring and scaling easier when sketch is symmetric.

Workarounds sounds reasonable for now, I hope more types of sketch constraints are in 'the list' already.

Rectangle by midpoint would also be wellcome, I tried this on solidface and it immediately felt good solution. This way you wouldn't need to add symmetric contraints for rectangle as it could be snapped to origin or plane/axis from it's midpoint.

To have something more than existing cads:
How about 'automatic mirroring' in sketch mode which you would toggle on and select axis (or reference line) for mirroring and it would automatically draw the other half? There should be a way to remove mirror constraint afterwards and modify mirrored half as it was created manually. Or even better change some part of mirrored sketch to reference figures and make some modification to other half and still have benefits of mirror constraints.

I would give my votes for everything that saves me time and clicks while repeating same workflow again and again.

brucebartlett

3dcad said:

I'm missing symmetric constraint also. It makes mirroring and scaling easier when sketch is symmetric.

I vote for symmetric constraint, I've already put in a ticket 2558.

3dcad said:

Rectangle by midpoint would also be wellcome, I tried this on solidface and it immediately felt good solution. This way you wouldn't need to add symmetric contraints for rectangle as it could be snapped to origin or plane/axis from it's midpoint.

This is already there on the drop down under the rectangle tool.

jakeramsley

3dcad said:

Rectangle by midpoint would also be wellcome, I tried this on solidface and it immediately felt good solution. This way you wouldn't need to add symmetric contraints for rectangle as it could be snapped to origin or plane/axis from it's midpoint.

As Bruce said, we have center point rectangle which is under the drop down of 2pt rectangle.  Is your idea of rectangle by midpoint different than how center point rectangle currently works?

3dcad

Are you sure you didn't implement it after my post - I double checked before writing..  
With a quick test it seems to do exactly what I wan't, it replaces the need for symmetry constraints for rectangles.
Could it be possible to add measurement on the fly ie. not having to use dimension tool afterwards?

berne

I put in my ticket only minutes after trying out the  product... I use the symmetrical constraint on almost every SW sketch I create.

Ticket 2402

andrew_troup

Symmetrical constraint is one of the most useful CAD tools I know for simplifying constraint schemes and capturing design intent, and the way it's implemented in Solidworks  is (it seems to me) perfection.