Position Representations in Weldments not allowed?

[Anonymous]

Does Inventor 10 not allow position representations to be created in Weldments? I Right Mouse Button (RMB) click on "Position" under "Representations", but "New" is grayed out.

[hemmlerP6BJD]

Hello Johnson,

Post 3 and 6 have put it very simply - there are (lots of!) cases where you need positional reps in weldment assemblies. And those examples didn't involve "shape changes" either.
Siemens (NX at least) has no problem dealing with this btw..
I posted this elsewhere already: we manufacture ball valves - "fully welded" products that are also very much mechanisms. And we would love to not have to work around this major limitation...

Best regards
Hendrik

PS. feel free to contact me regarding details of our use-case!

[johnsonshiue]

Hi Hendrik,

My prior postings tried to explain why PosRep isn't supported in Weldment/Assembly Features. It is because PosRep cannot deal with change in geometry. I am not saying it isn't needed. Nor do I reject its necessity.

Starting from 2022, Model States can be leveraged for your purpose instead of PosRep. On 2023, Model States also support Overlay views in drawing (similar to PosRep). Have you tried it?

Many thanks!

[hemmlerP6BJD]

Hi Johnson,



not yet (model states). But my point is that there strictly isn't any change in geometry towards the weld beads.
Not even as in the hinge example, which shouldn't stress Inventor too much in my opinion...
I'd really like to contact you directly to show you my current assembly. Could you perhaps DM me your Mail address?



Best regards
Hendrik

[johnsonshiue]

Hi! Absolutely, my email address is johnson.shiue@autodesk.com (also shown in the signature). Please feel free to contact me directly.

Many thanks!

[6.Day.Old.Filet-O-Fish]

It's unfortunate and bizarrely short-sighted that functionality was limited in this way. It's not always a designer's job to critique why a model was set up some different way at some different time under someone else's guidance. I have a 40,000# assembly which at some point a designer turned into a weldment (99% of it is welded steel, so it makes sense!). I want to animate the one pin that's been put in it, that has been in it forever, that's in the BOM and is now in drawings w/ it being produced by others in other departments. 🙄

By that logic, why have bolted connections, clevis pins and spur gears in weldments? What other features is no one asking to be removed?

[will3X6V4]

Johnson,

From what I can tell, model states is distinctly NOT relevant.

As described earlier -- there are many assemblies where a free-moving component is rendered captive by a secondary welding process.  A standard door hinge that has two leaves and a pin.  The hinge is a single assembly, with a cost code, and should appear in a certain order in the BOM; however, if you weld each leaf to another part -- you lose access to the positional representations.  Welding each leaf does not prevent the pin and knuckles from rotating freely.  There is no change in geometry of any parts and the welded connections have no change in geometry.

The change is positional only.

The desired use is specifically NOT trying to modify the weld or the geometry around the weld, but to modify the position of unconstrained entities.