Why cant a loft from tube to smaller tube?

RyanAvery

I want to make a tube basically get smaller on the end. I started by offsetting the end of the tube with a plane, then drew the ending sketch, and tried to connect the two with a loft, but it doesnt work. Whenever an operation in onshape fails there is no information as to what I can do to fix it, it just says that it failed.

RyanAvery

The error says "cant use profiles with inner loops"

Jake_Rosenfeld

@RyanAvery

The error message and red highlight is trying two show you that the the region you are trying to loft has a cut out region in the center, which our loft does not do, because it is somewhat ill defined what it should do.  To get this to work, you will need to loft the entire large circle to the entire small circle (you can use the dropdown arrows in the selection box to add additional regions to each profile, so each profile in this case will consist of an inner and outer region)

Then depending on how you want your geometry to look, you have two options:

• Use the shell feature to shell out the inside of the loft.  This has the advantage of keeping a constant wall thickness
• Do another subtractive loft from inner profile to inner profile.  This has the advantage of giving you additional control of the shape you wish to subtract from the outer loft.

Feel free to reply again here if this is not clear.