Uploaded for a blog post:
A few more photos of the elements used to lock up a chase for letterpress printing.
This shows the 7" x 11" (inside dimensions) cast iron chase, wooden furniture, quoins, key and Boxcar base. The only reason I'm using the wooden "£" is because it's more fun. When it's time to print, I'll use photopolymer plates mounted to the base on the left.