How to do extrude cut or similar?

CSC65

Hi folks. I'm trying to model a train's sand dome which sits on top of a round boiler. I would like to cut out a flange to sit on top of the boiler, which the dome sits on top of. How can I cut out the flange piece?

See video example here @2:40:  https://youtu.be/Xfv6L9jD988?t=174

The OnShape model is here:  https://cad.onshape.com/documents/de5c33edf5a6d69bd3590039/w/b19e20837afdfed0f287276c/e/b93f843a543d8b5c2dd3546d?renderMode=0&uiState=62e354401e8eaf63aa69d03a

I'm migrating to OnShape from another well-known CAD program, and so far I'm really liking it.

Thanks!

Chris

CSC65

I was able to solve the problem using boolean intersect. As long as the geometry is clean, I don't really care how I get there.

Thanks again.

C.

steve_shubin

@Chris_148

https://cad.onshape.com/documents/ba04993421326371612f786a/w/43f92c648deb9477e502c96a/e/75f831259b2bd25a6686e62f

well here’s one way

I did not use a loft to make the fillet

Of course I could’ve did it the way the guy showed in the video

But at the 7 minute and 50 second mark in the video, he says that the longer fillets are not tangent

The way I did it it’s all tangent

The difference is, doing it the way I did, the top of the fillets are not all at the same elevation when you go around the entire circle

But if you wanted it like he did, yeah you could do it that way. You could do a loft to make what looks like a fillet

eric_pesty

Didn't watch the video but these kind of shapes are best done using surfaces:



Here's my attempt:
https://cad.onshape.com/documents/4f3df1d6c5cc0460c861a4af/w/9b13a1092342b980cd248597/e/21bacc68fe74ff486e3bcc6f

eric_pesty

Note if you want just the dome as a separate part you can do this:
https://cad.onshape.com/documents/4f3df1d6c5cc0460c861a4af/w/5280f9235f1df31608d4d507/e/5e27b3fd8e88249582c4b88a?renderMode=0&uiState=62e41da9b15a2f276b663ca4

CSC65

eric_pesty said:

Note if you want just the dome as a separate part you can do this:
https://cad.onshape.com/documents/4f3df1d6c5cc0460c861a4af/w/5280f9235f1df31608d4d507/e/5e27b3fd8e88249582c4b88a?renderMode=0&uiState=62e41da9b15a2f276b663ca4

This was the closest, but I need to be able to 3D print the final design.I am interested in knowing how you were able to use my "boiler cutter" sketch to project onto the "boiler" to make the flange piece. Lofting the curve between the dome and this flange is a whole other discussion.

Thanks to everyone for trying!

C.

CSC65

I was able to solve the problem using boolean intersect. As long as the geometry is clean, I don't really care how I get there.

Thanks again.

C.