I have made many new parts for my Tantillus, which I now call an Ultius, and had to remove the upper corners many, many timers. It was really tedious having to do it in a certain sequence, so I quickly cut away pieces with my Dremel. This is the printable corners, which you can put on even when all the rods are in place.No special instructions. I always print with at least 3 or 4 perimeters (n times your nozzle size) and 0.2 layer height. I have printed these both with 25% and 35% infill. Worked fine both ways.