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Problem with sweep

https://cad.onshape.com/documents/fa1ca25753015222ccc78242/w/539dfcfd740f84ec267c79e1/e/577b4a4d49546eb468a31dc2
Hi, need some help again! I am attempting to complete the part in the above document by merging the screw flights so they are continuous along the profile. I have tried the boolean union, but this brings back an error. Can someone advise how to do this?
Another related question is why I cant get the helix to extend over the joint line since it is not two parts?
Thanks in advance.
Peter
Comments
The Part 2 intersects the Part 1 at a knife edge, meaning the Boolean will fail with the error message you are seeing "Boolean operation would result in a non-manifold body"
Solution is to use a Replace face feature after the first Sweep to get rid of the "hanging" face. That small face is highlighted here. Replace it with the conical face and you'll be ok.
Ha ha I wouldn't have spotted that in a month of Sundays! Thanks for the advice, much appreciated.
Worked a treat, thanks Greg