Can Anyone Identify The Cachet Maker On This 1933 World's Fair Event Cover?

Starting to work through my backlog of unimaged half-cent postage due covers.

Somewhat crude cachet, great cancel, and fractional cent amount due to boot.

Any explanation of the 1c Green?
Looks via the part Pmk, as if it has been added later.

The 1c stamp belongs; it just didn't get tied. The ink looks the same as on the special 4-bar cancel. Turn the full cancel at left upside down and cover most of it with a slip of paper and you get that philatelically photogenic cancel. That was done often enough on philatelic covers. Note that partial vertical frameline that matches the box around the exposition blurb. There aren't very many 4-bar cancels that have a box within the bars and the size and spacing likely match the special 4-bar used for the postal car exhibit.

20/20 vision, nicely spotted. Thanks HB.
Your explanation is utterly believable, but sure is weird, all I can think is the cancel for that piece , the hammer (or cover) must have been upside down.
(To receive the end of the Pmk)
Perhaps the mail car was cancelling multiples of the cachet, at the time,
and one cover was upside down.

Dan's cache is new to me, never seen anything like it.

I agree with post that said the cancel is upside down. Here are few more cancels including a Last Day* cover.


Don


*Last Day for 1933. After closing the Fair in 1933, it was decided to reopen in 1934. This decision helped the 1933 Worlds Fair to be profitable, something that was/is unusual (especially during a period of Depression).