How to delete faces from an import (solidworks or iges)?

reuben_kraft

Hello,

I was able to successfully import a part from SolidWorks and want to edit the part. Some things I can do like extrude, split curves, etc. However, if I try to delete a face, the "Delete face" item under features is red and when I hover over it, it says " Delete face 1 did not regenerate properly: Select faces to delete"

I was wondering how I can do this. The reason I want to delete faces is to simplify or de-feature the part (I plan to send to simscale for simulation). My plan was to delete and add a simplified geometry component that is more easily "meshable".

Thank you.

Jake_Rosenfeld

Hi Reuben,

Can you share your document here or post some screenshots for context?  My best guess is that you are just selecting the bottommost face of a pocket or the topmost face of a protrusion.  To defeature you will need to select all the faces of a pocket or protrusion.  See the direct editing video here:

https://cad.onshape.com/help/Content/deleteface.htm

Let us know if this was your issue or if there is an additional problem.


EDIT: The specific text of your error message seems like there aren't any faces selected.  Is anything showing up in the box above the 'Delete fillet faces' checkbox? It should say something like 'Face of <something>'.  

Reminder: if you are using the 'Create selection' dialog you will need to click 'Add Selection' before that selection actually makes its way to the 'Faces to delete' box of the feature dialog (I think this is probably the problem you are experiencing)

NeilCooke

See here: https://cad.onshape.com/documents/58c10cdf78c5f50fe8b5f74d/w/c3d34e0c7621cf231e2986c6/e/d6f7e6dd54eca3949ff0bccb

Jake_Rosenfeld

Hi Reuben,

Can you share your document here or post some screenshots for context?  My best guess is that you are just selecting the bottommost face of a pocket or the topmost face of a protrusion.  To defeature you will need to select all the faces of a pocket or protrusion.  See the direct editing video here:

https://cad.onshape.com/help/Content/deleteface.htm

Let us know if this was your issue or if there is an additional problem.


EDIT: The specific text of your error message seems like there aren't any faces selected.  Is anything showing up in the box above the 'Delete fillet faces' checkbox? It should say something like 'Face of <something>'.  

Reminder: if you are using the 'Create selection' dialog you will need to click 'Add Selection' before that selection actually makes its way to the 'Faces to delete' box of the feature dialog (I think this is probably the problem you are experiencing)

reuben_kraft

Thank you Jake for the fast reply. Here is the link:
https://cad.onshape.com/documents/a4dae015a67dfc4426a9e0df/w/dcd99f9ba4b00eb472e5c793/e/f4cd6897690bdf6455b486d6

I was trying to delete any of the outside faces. I think you may be right that this is the topmost face of a protrusion, but I am not sure where the base sketch started. 

Jake_Rosenfeld

Reuben,

See my edit.  Are you sure there are actually any faces selected for the deletion?

reuben_kraft

Yes. I believe so. It appears in the delete faces box "Face of Import 1". See attached image.

Jake_Rosenfeld

Hmm strange,

I'd like to try a couple things, is there any chance you can make the document public so I can copy it and play around? If you'd rather not you can file a support ticket by clicking '? -> feedback' in the upper right corner of the document.

reuben_kraft

Done.  Document is now public.

reuben_kraft

Also, here is link where the original SolidWorks part can be downloaded.
https://drive.google.com/open?id=0B2jKCiWMO3weZEQxNmRrUzlOYWs

Jake_Rosenfeld

Hi again

I defilleted everything just so you could see how it's done.  Let me know if this isn't what you meant to do:

https://cad.onshape.com/documents/58c051f8e493aa0f85abe0cc/w/fbe091f472b0f64e5348c638/e/cbd31a606b5bda61d936d303

If you want to be able to see the inputs to the features by rolling back/double clicking on them, you can copy the document back from me.

brucebartlett

It will not delete the face because this would cause the solid to become non-manifold. If try the fillet this work perfectly.

You could use the move/create face command and convert all other faces except this to surfaces to but not sure that's what you are really after.

I think what you want is just to extrude the face in with a remove, is this the result your looking for.
https://cad.onshape.com/documents/58c0538015bae2107af929d9/w/530b09d343b9976a228105a6/e/72830c3d67b81962fba02e53

reuben_kraft

Kind of, I am interested in your steps to defeature. How would I do that?  However, when I select a face from your version and try to delete it I get the same issue. Let's say I wanted to delete the faces on the circular protrusion on the model, so this would make the outer surface like a box without a protrusion. I know that there are faces associated with the geometry that will need to be closed up if I delete certain faces, but it seems like onshape does not want me to delete certain faces that create holes? Is that the issue?

Jake_Rosenfeld

Reuben,

I don't think delete face is the right workflow for this because it is not a solid protrusion. I've done what you want with 2 'Move face' features:

https://cad.onshape.com/documents/58c051f8e493aa0f85abe0cc/w/fbe091f472b0f64e5348c638/e/cbd31a606b5bda61d936d303

reuben_kraft

Hi Jake and Bruce,

Yes, thanks so much. I think I understand what you both are saying with the 2 move successive commands. I played around with it a bit and see how that would work, although I am not sure how you sealed up the hole. This problem is a practice for what I am really trying to do and that is to remove a similar structure but is threaded. I have a circular piece of a part that looks just like this but has threads. I want to remove the threads so I simplify and can make a finite element mesh. 

So next question, is how would you remove complex faces like are on threads? Sorry for all the emails, but I think this sort of thing would be useful for the general community.

reuben_kraft

Here is the link to the threaded part I am trying to simplify.
https://cad.onshape.com/documents/54911a92f479626781c654b3/w/af59c558d5fb80b48b2383a6/e/f3126373a0965d466532fb08

NeilCooke

You should box-select the entire thread area and unselect the end face to delete the entire thread - you would then need to add the chamfer back afterwards.

reuben_kraft

Thank you, Neil. I would love to do this, but I get the same error like "Delete face 1 did not regenerate properly: Select faces to delete". See attached image. I think Onshape does not like that this would create a hole, which I understand, and I want to fix, but I need to see the hole before I fix it. 

NeilCooke

See here: https://cad.onshape.com/documents/58c10cdf78c5f50fe8b5f74d/w/c3d34e0c7621cf231e2986c6/e/d6f7e6dd54eca3949ff0bccb

reuben_kraft

Got it! Thanks. I think maybe one issue I was having was when I de-selected the end face, I was actually de-selecting one of the back edges, which blocked the operation. Thanks so much for all the help.