Ad a loffted surface to an extruded part

rob_field

I am trying to create a model for an exhaust flange that lofts from the port shape to a round tube. I have created the flat flange and the loft section, but I can not get the two pieces to come together as one part. I have tried a couple of different approaches as you can see in the document, but nothing seems to be returning a valid part.

https://cad.onshape.com/documents/cf460d82e18d984d97401c49/w/c8952f7c53812b04bb7d945b/e/6976b14c1262af6e1431cabd?renderMode=0&uiState=64598fe9a11d8e4e151bbee3 

S1mon

Here's a possibility (there are a zillion ways to do this) https://cad.onshape.com/documents/0f969e40417eb6927d687567/v/8b01953c800d10e90fb7535d/e/2ff76431fddafcae6c2bcb32

A couple things:

1. Not really necessary, but I added some splits to the circle of the loft, so that the connections from the ob-round make a nicer surface.
2. I replaced the bottom surfaces of the thickened tube with the surface of the flange, and then boolean/unioned them together. I added a fillet just to show that they are one thing now with no funky gaps.

eric_pesty

You'll get better results lofting as a solid and hollowing it out with a shell, then you can merge with a boolean. the thickened surface approach causes the ends to be "irregular" because it thickens normal to the end.

Also note that you can use the "connections" in the loft instead of the guide curves.



https://cad.onshape.com/documents/8d280abb276f59b95c03e610/w/b74dd3d051420adfc9699474/e/887edad32e6965267733748a?renderMode=0&uiState=64599d18e72cef35a8d60790

eric_pesty

I was going to add, the solution with the thickened approach is to do "replace face" on the bottom end, which then allows doing a boolean:



https://cad.onshape.com/documents/8d280abb276f59b95c03e610/w/e696ed0e39b711b6908484b9/e/887edad32e6965267733748a?renderMode=0&uiState=64599d0de72cef35a8d60785

rob_field

S1mon said:

Here's a possibility (there are a zillion ways to do this) https://cad.onshape.com/documents/0f969e40417eb6927d687567/v/8b01953c800d10e90fb7535d/e/2ff76431fddafcae6c2bcb32

A couple things:

1. Not really necessary, but I added some splits to the circle of the loft, so that the connections from the ob-round make a nicer surface.
2. I replaced the bottom surfaces of the thickened tube with the surface of the flange, and then boolean/unioned them together. I added a fillet just to show that they are one thing now with no funky gaps.

That is exactly the result I was looking for thank you. I had a feeling I was just one step away from getting it right and the replace face was that step.