Filament Spool Holder or Spindle Bobbin for Ender 3 47mm

When I got my Ender 3 I was surprised at the way the reel of filament just hung on the spindle with no apparent thought to enabling the reel to turn easily.

What I felt it needed was a spindle adapter (or bobbin) which would make the spindle sit at the middle of the reel. This would mean the filament tension would only have to cope with a radial load rather than in effect having to lift the reel as well to spool off more. So the reel can turn more easily.

So I designed three. They differ on the diameter of the central hole of the filament reel. As bobbins they have to slip on and off the spindle easily so there has to be some vertical slack but it is significantly reduced by the bobbin.

This one supports supports 47mm diameter hole reels. See my other items for the other two (76mm and 56mm respectively) In fact the bobbin exterior diameter is only 44mm giving some leeway for tolerences on 47mm reels.

The bobbin slots through the Reel and then over the Ender 3 spindle. It is retained in position by the lip at the far end of the Ender 3 spindle.

It really does seem to help prevent the damn thing from over tensioning the filament and besides, its looks better too. Although the main problem is with the bigger diameter spindle holes, this 47mm bobbin still helps the filament flow easier. (IMHO anyway)

Note: I have not built this exact bobbin. I built this 47mm bobbin but I fouled up and it was just too long to sit properly on the Ender 3 spindle. I had to saw off about 2mm. Consequently I shortened the spacer in the Freecad design by 2mm and generated new STL and gcode files. So this one should sit on the spindle fine.