I've printed this using the updated file in the zip with the makerbot mini using PLA plastic. The only problem I had was when I went to spin the screw the plastic knob broke off. I replaced the 15% fill screw and knob with a 100% fill knob and screw. It works perfect now. I also did notice while printing the 100% fill knob near the end of the print the makerbot mini would wobble slightly making the threads on the inside of the screw where the knob and the screw meat be un alighted so I had to sand the threads on the knob down to fit it into the receiving hole. I hope this was helpful.