Square corner platform for a birdcage. Originally I attached it with nuts and bolts from the garage but for the purist in me I had to make some 3D printed ones as well.  I included the FreeCad files so feel free to make any adjustments you would like. I printed the bolts and washers on .2mm and they go on by hand easily. I think if I printed them on .16mm they might be even smoother but I didn't find it necessary.