Symmetrical constraints

[#1]

I'd like the ability to create symmetrical constraints, so I'm not required to work around this via other methods. 
It would allow me to work faster and with more assurance.   Also, I'd like the option to select symmetry based on various points, lines, planes. Etc.

[#2]

Again this is already posted but why?

Offset constraints is a big no no . Use a sketch instead trust me.....

[#3]

as i read this, the key word is symmetry, not offset.

ie the o.p. would for example (in one case) be contraint locking mid plane of one object to midplane of the other object. in inventor we have to use workplanes etc for this. other products allow symetrical (along with various other) methods of symetrical contraining, even if there was no mid plane or symetrical origin plane to use, we could pick various object attributes on the fly to allow us to place our contrainsts in a quick and efficient manner. mechanical desktop was a fine example of this excellent functionality.

"sketch instead" is a pretty vague statement. if this refers to using sketeton geometry and parts being located according to their position relative to a master sketch or skeleton then yes this is alaso a great method. sometimes the environment that we work in dictates one method over the other.

having the new idea would not diminish the operation of those who prefer other methods or have to work one way or another.

it took inventor quite some years before some functionality of MDT came through. i am surprised that this has still not yet been given the green light.

[#4]

this is easy people. create your parts assemblies using the origin planes. Begin the sketch of each component relative (symmetrical) to the origin if that is your intent.  when you place the component the insertion point of the model IS the origin on the first sketch and when all your parts are created in the same way the same origin planes in each part can be constrained together to maintain position independent of the size of either part.

Basically, each time you start a part you must consider the datum in the original sketch and position the sketch accordingly.

[#5]

Mark_Wigan,

  No sketeton geometry is not what I mean but can be used.

Also in order for somthing to be symetrical would it not be an offset? if you have a mid plane or the orgin and you want a part to be symetrical from the one plane would this not be an offset constraint from that plane?

tmoxam,

 No you do not have tho think or consider the datum in what I am saying.

To explain:

 I have two parts part "A" and part "B".

Now Part "A" is grounded and I want Part "B" to be located 1" from the edge of Part "A".

So what I would do is double click part "A" start a sketch on the face make a construction line and dimension it from the edge 1". Finish edit and constrain part "B" to the line.

No sketeton geometry is needed unless that is the way you wish to do it.

But the one thing I want to make clear is an offset constaint is not good for many reasons....

[#6]

jletcher,

If I read this correctly you have two components in an assembly. You ground, or otherwise constrain part A, you then create an assembly sketch of a line with one end constrained to part A. Next you exit the sketch and finally constrain a surface on part B to the other end of the line? I would be open to learning the logic of this method. To me it looks like you are doubling your work and leaving part B able to rotate with respect to part A rather than constrained with parallel faces.

I know you want to make it clear that offset constraints are not good, but I have not found any reasons for this. Again I am open to learning what they are.

Jim

[#7]

@ JimSteinmeyer

   No you don't use a assembly sketch.

Lets say you have two parts part A and part B.

Now when you start an assembly and insert part A this part would be grounded.

Now you insert part B now lets say part B is mated to part A flush at the top mate to the face now part B has to be set back from the front edge about 2 inches. Most would us a offset constraint this 80% of the time will make your assembly explode out of the blue and you don't know why.

Now instead of an offset constraint open part A put a sketch on the face part B is mated to on the sketch draw a line and dimension it 2" from the edge you want part B to be offset from. Finish sketch.

Go back into the assembly and take part B and put a mate on the face of part B to the sketch of part A.

Now most the time I will name the sketch in part A so I know it controls the location of part B.

No offset constraints and never ever had issue with exploding assemblies or issues when I go and make it adaptive.

If this does not clear it up I could do a small video and upload it to you tube for you..

[#8]

Accepted idea [US5155]. Thanks!

[#9]

This idea has been implemented in Autodesk Inventor 2014.