Hello, over time I had accumulated few boxes of bad prints. It seems too much of a waste to throw them out but they are useless. If there is a way to melt them down I can probably make a full roll of filament or two. I have no idea what to do with them. How do you guys handle bad prints? Thanks.

There are some design for DIY pellet extruders to make your own filament. But you have to make pellets from your waste plastik.
The quality of the DIY filament would probably be good enough for infill. A dual nozzle printer would "save the world" then