I lost my handle so I made these to hold the rest of the blades. The print is tricky since you have to pause at the right layer and insert the hot razor blade into hot plastic in a hot machine. So be careful. Repetier at least does the pause simply with a @pause command on a certain layer. It seems to print OK at with a .3 slice at .3 fill. I leave the blade(s) on the bed to get hot up until it is time to insert them. The trick to this is, like several of the penny bottle openers, to pause at the right layer. That would be right before it goes to layer over the .5mm blade slot. There I place a Repetier host @pause command (which plays a klaxon for me) in the gcode. When that triggers I then home Y, seat the blade and resume printing. This is not for the faint of heart given the 100 ways imaginable this could go wrong and destroy life, limb and property. And so, no guts no glory, have fun.