This is a fast and easy model that I designed in order to test 3D model dimensions versus actual print dimensions on all 3 axes of my printer (daVinci 1.0 Pro). The overall print size is 6.0" x 6.0" x 0.75", but I've included several features to test various things: 1)  Overall dimensions of 6.0" x 6.0" 2)  The dimensions of 4 different square blocks (1" x 1" x 0.75";  1.25" x 1.25" x 0.5";  1.5" x 1.5" x 0.375";  and 2.0" x 2.0" x 0.25").  The 2" square has a 1" x 1" square removed from the center, for testing inside dimensions on the X and Y axes, as well as perimeter distances of 0.25" on all sides. 3)  A 2.5" diameter cylinder with a 1.5" inside diameter, for testing circular concentricity. 4)  In order to test fitting for fasteners, I've included four (4) different openings for 1/4-20 machine screw nuts.  I physically measured part #MS-110 from Bulldog Hardware, and included four different tolerances within the design:  Zero tolerance, 0.01", 0.02", and 0.03" tolerances.  (These tolerances are measured from flat to flat on the nut... so are actually half of the tolerances listed.)  Each opening is 0.192" deep, which should let the above-listed part number lay inside the opening with its top surface flush with the printed test part.  I've also included a 0.325" diameter hole at the center of each opening, to help push your 1/4-20 test nut out of the opening(s), if necessary. As you can see from the preview images, I took the time to label each feature of the test object (other than Z heights).  I also added some small cross-members to hold the part together, should you want to save the test object for future reference. I have the original TurboCAD v16 file (with all 3D parts, dimensions, and subtrahends) available for anyone who might like to adjust some dimensions.  Simply message me, and I can send you that file. I used white PLA from Cutequeen (which I've had great luck with, by the way) using 200°C extruder/45°C bed temperatures.  The estimated print time is 4h:26m using 14.97 meters of filament... at 10% infill with 0.3mm layers and no raft or support.  I've only uploaded the Netfabb "fixed" version, since I found one small hole in my original .STL file. Enjoy!