Having trouble mating a part to a tube

I have a threaded Boss that I need to mate to a duct, but I can't quite get it flush, there's always a bit of a gap. The only constraints I have are the 45-degree angle and the distance from the edge (see the pics for reference). The OD of the duct matches the Boss so it should fit, but I think the bend in the duct is what is giving me the issues.

Any help/tips would be appreciated!

Accepted answer

The bend of the elbow is obviously why the threaded boss is not fitting correctly.
The threaded boss has been cut to fit on a cylinder like a saddle fitting. But that's not what you have here.

Either the threaded boss needs to only be in contact with the cylindrical portion of the elbow. Or the cut on the threaded boss needs to be more complex to match the compound curvature of the of the elbow.

Either of the above options is easy to do in SW. Only one is easy to manufacture in real life. The end decision is up to you, and comes down to where that threaded boss needs to be, and the available budget for machined bosses, and welding fixtures.

1 Other answer

The 45° bend is the reason, of course...
Instead of cutting the small part with a Boss feature, use a "Revolve" or a "Swept Cut".