I am currently very close to having a working Nurdle to filament extruder. So now some way of collecting the hot freshly extruded filament is required. My first thought was to automate an existing cable spindle so that it slowly rotates to take up the filament as it comes out of the extruder.
Right away there are a few problems with this idea. After extruding around 30cm of filament its own weight becomes enough to cause it to pull away (string) at the point where it just extruded and so still molten. So the tension caused by a slowly rotating spindle will also cause the filament to stretch and break at this hot point.
On possible solution to this could be to have a small 12v fan (image below) directed at start of the extruded filament so that it becomes cool enough to be handled. At this point, around 10cm beneath the extruder, two rotating shafts could gently grip the filament on its way to the spindle. This would take up any tension created by the spindle or the filament its self so that no force is applied onto where the filament exits the nozzle.
In the image above I have two salvaged stainless steel shafts that could be placed together to grip the filament see between them. The rubber could be cut to shape so the filament doest lose its round profile. The filament would then be cooled further by a vertical mounted blower fan, also seen in the image above.
Here is a sketchup of the whole idea.
The top object is the drill press, the bottom is the spindle. The spindle and the board its mounted on is suspended by a weigh scale. This is so the amount of filament spooled can be known on the fly. A DC motor drives the spindle and a second motor drives the feed rods at the top. A fan is located with the feed rods and level with the spindle (the shaft looking thing).
Before investing hours in building this I’m interested to hear if anyone else has a better solution. So if you have any thoughts at all please let me know.