I recently received a loco I bought which was shipped via USPS.
Several times now I have had heavy locomotives shunt back and forth in their apparently snug, original foam shaped boxes. You cannot let any movement happen at all. Never trust the foam box.
Firm padding at the buffer beams so the loco can’t move is the only solution but not too many understand and put their faith in the original box’s design as it seems secure.
The problem in this case was that the cab is secured by the foam but the heavy lower part of the loco is free to move back and fourth. This usually happens with long heavy locos and I assume the shipping handlers habit of regularly dropping them on their ends.
I have had this happen to several locomotives now, Usually LGB and LGB/Aster as they always seem to have some jiggle. Some survive but chew out the inside foam, others shunt back and fourth breaking things.
This is why Accucraft locos are mummified.
This is why Bachmann and AristoCraft are tightly wedged in.
Fair Warning to all those who are shipping a heavy locomotive.
Andrew