I've created a new assembly. In that assembly I've inserted an existing part (weldment frame).
I'm creating additional parts with in this assembly by:
1) Insert / Component / New Part
2) Selecting my plane (Usually the face of one of my weldment beams)
3) I then begin creating my part, now that I'm in "part mode" (using relations).
4) I then want to take that newly created part and make it a part of it's own. I do this by RMC on the part and selecting "Save Part (in External File). Works great.
I then create another new assembly, but the parts aren't coming in at the location/orientation I created them. Example... I create a new assembly, insert my weldment frame, then insert any additional parts I created... The additional parts I created aren't coming in at the location/orientation I created them.
The appear to be coming in on the default planes... not the planes (surfaces) I selected.