Copyright (c) 2017 Bart Massey
This 3D "thing" is a FreeCAD 0.16R part model produced by following a Hackaday 3D Printering Tutorial. The part itself is from the book A Manual of Engineering Drawing for Students and Draftsmen by Thomas Ewing French, 1911. The second 1918 edition is available online through Google Books , although I can't find this drawing in there since the figures have all changed.
The Hackaday tutorial is great overall. I had a few minor quibbles:
It would have been nice to have the book drawing enlarged and cleaned up so that it was more readable.
Apparently Freecad 0.12 had trouble with units. With 0.16R I followed the book drawing and used inches for everything. Seemed to work fine.
The construction of the slot in the base should really be explicitly such that the center of the slot hits the center of the hole. I fixed this in my version.
The construction of the fillet between the washer and foot part of the base should really be explicit in the sketch, given that it is fairly explicit in the book drawing. I tried to reproduce it accurately.
It is not obvious from the book drawing how the top of the flange piece should be shaped. After staring at it for a long time, I diverged from the drawing and made the sides of the flange vertical instead of sloped. To change this, remove the vertical constraint in the flange sketch and figure out how high you want the top of the flange to be.
The tutorial handwaves some idea of making the base and flange pieces fit together by doing some math and adjusting sketch positions manually. I did this first, but didn't like it. I instead chose to go through the sometimes-painful process of making sure sketches were attached to appropriate faces and appropriate geometry was borrowed: as a result, things are more reliable and configurable.
I've included STL exported from the model, just for fun.
Anyway, have fun taking this apart, printing it, whatever. Thanks again to the tutorial authors for an interesting afternoon.
This work is licensed under the "MIT License". Please see the file COPYING in this distribution for license terms.