Best method for resolving a swept-cut self-intersection

david_lawless

I am attempting a swept-cut and running into a self-intersection error. The preview of the feature illustrates fairly well what I am looking to accomplish. I'm brand new to Onshape, so curious what might be the best practice for creating this type of feature, or resolving the geometry.

Document

Thanks

GregBrown

There is no way that profile will sweep around the path without self intersections. To make it easier to see why, I sugges making a sweep surface and only choose the two edges of Sketch 5 as seen below:

You can see the obvious self intersections...

My suggestion is to approach with with a loft feature - make some profiles (the 30mm diam originating arcs from Sketch 2 are good) and some guide curves. Sketch 4 is one guide, but you'll need to create two more on the top/bottom faces in order to control the shape. The quality of these guides will greatly affect the outcome - I suggest using a Bezier sketch and enforce curvature continuity.

Not sure it meets your design intent, but here https://cad.onshape.com/documents/fa71d088417ca9ecf79767bf/w/91dcdd9176474244290ffd5b/e/93d5bed96e3538ae36ea901e  is a quick one I created to show the above approach. Try tweaking the guide curves and see what happens. Of course there will be many other ways to get to a final shape, but this might help unlock some tricks and encourage more exploration!

MichaelPascoe

@david_lawless, Greg is right, this is what happens when you try to sweep something that intersects itself. There are a few ways to get around this. One way would be to loft as Greg mentioned. Another way would be to sweep only the section of the profile that will not intersect itself, then use other methods to create the rest of the shape. See this example:

https://cad.onshape.com/documents/bc44df417a18be23fa14cffa/w/11007c7f48bde72d90b20b5d/e/72bc05da8c...