I am trying to make a mold for a temporary rubber plug, And I'm not sure  the best way to do it. I need to be able to make it either larger or small than the feature I'm modeling it from. I got it working, then it broke, then I got it working, but then I find it's not really right. I modeled the plug thinking I could put it in a cube then combine/subtract, which worked pretty good actually.

What we want to do is 3D print molds for these plugs. It's the darned "spigot" on this thing that's making it hard for me to figure out. My best guess right now it to make it size on size, and just scale it on the printer software, which I don't think is right.