If the thread (solid Helix) end needs a run-out I Extrude the end face of the solid>Helix approximately the radius of the threaded shaft. That will normally give a good (visual) lead-out and means you only have the one Boolean (Subtract/Remove) to do. https://cad.onshape.com/...
Here is one way to do this with sheet metal. Make the tabs(flanges) as small as you need for curve approximation. https://cad.onshape.com/documents/feeafb87e93684b0f10c813b/w/ceb86e65fb96e6e9065eea91/e/19d921cb77ceccac3d639ba1...
Move the mouse and then click to end the segment. Move the mouse in the direction of the curve you want and click to curve the line. 4 Click the Rectangle tool to create a rectangle. The rectangle tool is simple—click the first point, which will be any corner of the rectangle, and...