Tweak Face

Extends a 3D object by extruding selected faces to a selected 3D detination object. The reuslt is an ACIS Solid.
The destination object must be a sheet body (ACIS Surface). ACIS surfaces/sheet bodies result when non-closed objects, such as a line segment, are extruded, revolved or swept. They can also be created from ACIS Solids by using the Create Solid from Surface from Solid tool tool, or by using the Create Surface from Profile tool  tool on a closed 2D object, and by using the Extract Entity tool tool.
Note: if the destination object is a closed volume, such as a sphere or closed revolve, thene the destination object will be solidified and added to the resulting tweaked object.
To use the Tweak tool:

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