Okay, I bought me Robo3D 2 years ago. I got 3 prints out of it, but it kept jamming. I was told then, that was a common issue and I should upgrade to the E3d hotend. I did and have never got it to work since. Initially it was acting like the extruder was on the bed: It would try to print for about an inch or two, then it would mushroom up around the tip and clog. I went back and fort mainly from this to other issues like an error indicating extruder was loose to it not melting the filament, though the hotend was still heating. I gave up and let it sit a few months. Now I'm back trying to make it print and am back to the not-melting-the-filament issue. Hotend heats, just no filament melts through. I have tried 3 types of filament thinking maybe the first was just old and the second was too cheap. I am now wondering if I either need to get a new hotend/extruder, or just play smashy smashy with it and end my suffering. Assuming I go the first route, what is now the best (and simple) hotend/extruder for me to try now?