When I ship frames I take crazy measures to insure that they will arrive safely.
1. Triple carton wall bike box on outside - much longer than frame 2. 2nd bike box cut at the corners and folded in to create front and rear triangles and under down-tube, over seat-stay triangles ... these triangles protect the frame and lock it in place 3. pipe insulation over every tube, followed by police perimeter tape. 4. dummy axles between dropouts. 5. folded carton between head-tube and front of box same between rear dropout and rear end of box 6. fork removed, pipe insulated, slid through seat tube, dummy axled ... with steering tube in front triangle box.
http://flickr.com/
This takes hours. I've only ever seen this done, and often much better than myself, by other collectors. One variation, is to cutt the outer box in the shape of the frame, thus drastically reducing perimeter measurements. This reduces shipping costs, but requires much more careful packing and much more time.
Most bike shops would laugh you out the door with such instructions.
Amir Avitzur
Ramat-Gan, Israel