How to get true to form model (Adding solid with thickness from surface)

[MatsNorway1]

I got this master sketch i derive parts from but the corners have no circles or flat surfaces to constrain to even tho the sketch is properly constrained and has circles.

I ground and root at origin for the first corner but i cant then reuse the same part for the opposite corner. There is no way for me to place it correctly as there is no flat surfaces or circles to constrain to.

I have used similar models in the past but for some reason this one is not circular on the outer edge or flat in the cut in the corners.

Any tips to make better derived parts or corners that are in effect, usable for anything?  i used thicken to turn a surface into a solid.

[mikejones]

Hi

Any chance of sharing the ipt file to have a look at what is going on as it's difficult to appreciate the problem from the screenshots. What version of Inventor are you using aswell?

Mike

[MatsNorway1]

Yes, see attached.Derive part and then try to assembly corner piece in all four corners to better understand the problem.

I am on 2022 version

[JDMather]

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@MatsNorway1 wrote:

I ground and root at origin for the first corner but i cant then reuse the same part for the opposite corner. There is no way for me to place it correctly as there is no flat surfaces or circles to constrain to.

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Can you Attach an assembly with an approximate placement (by eye).

I do not understand your Design Intent.

If you Select Other - you can select Points.

or...

if you want a point at pierce of the curved face...

[MatsNorway1]

Attached is assembly

[MatsNorway1]

Once assembled you will notice that any of the parts will not constrain to the corner.. or rather there is no constrain options for the corner piece even tho it is derived from a arc with a constant Radius.

[mikejones]

Firstly, that's modeled in a very strange way. Is there a specific reason not to model as a solid cube first and fillet the corners with the rolling edges and rolling ball options turned off?

But to get back to your problem. You are going to need to add some work planes; points or axis into the master ipt file and derive those out with each of the parts. You can then use that geometry to constrain the parts together correctly using the flush and mate constraints. You could also look at using the UCS function to create the 'Connection Points' and derive those into each derived component.

Mike

[MatsNorway1]

Do you then create a surface from the cube and add thickness to the parts before deriving?

[mikejones · Accepted solution]

Yes correct. You still have the same problem for constraining but the modeling will be a lot quicker and more straightforward.

[MatsNorway1]

How would you do if you needed it to be constrained?

[mikejones]

I would add in a work point on the intersection of the corner faces and 3 work planes on each of the 3 sides next to the corner piece you are going to derive out. Then derive those work features into each of the derived in parts and use them to constrain together.

I've attached an example zipped up for you to take a look at.

To be honest, I'd probably just derive all of the parts separately and then just rely on the grounding function to position them all.

Mike