LMS rigid chassis Sentinel steam railcar
Sentinel built steam railcars for both the LMS an LNER. The LMS tested a prototype lightweight version (similar to the LNER lightweight ones), and subsequently ordered some slightly altered versions themselves.
Only one rigid chassis version was produced for the LMS. It outlasted the articulated versions but was scrapped in 1939.
OO scale (1/76 4mm/ft)
----------------
more info about LMS Sentinel railcar here
http://www.lmssociety.org.uk/monologues/M14.pdf
more 3d printed models from Recreation21 here
http://www.rue-d-etropal.com/3D-printing/3d_printed_designs.htm
------------------------