For our first subscription filaments we recommended the use of the MasterSpool to hold the filament in our posting Effective Loose Coil Handling for a Positive Experience. This was primarily due to the core size we use on our spools. It may not be well known, but the center core of our spools are larger to provide a better extrusion experience. Spools with a smaller core size result in filament having to bend more to get through the extrusion path. This bending back of filament often results in breakage in the extruder. To avoid this negative experience we use a larger diameter core to reduce the bend radius on the filament. The MasterSpool has this same core size and so it seemed a great fit for our samples.
However, while the MasterSpool does a great job of holding the filament it is a full size spool and therefore requires a bit more material to print and more time as well. So we decided to come up with a smaller, lighter sample spool that would fit our sample coils perfectly and not require as much material or print time.
We've designed our spool to print in less than 50g of material per side using 2 perimeters, 2 top and bottom layers and 10% gyroid infill. The design is available on Thingiverse as thing:3807199.
We created spots specifically for the head and tail of the filament coil to go. The head being held such that coming out isn't really possible and the tail should come out nicely as the last little bit of filament is being used. There's just enough friction there to keep it in place while handling but not too much that the extruder can't pull it out of the spool, saving from the extruder pulling the spool off and possibly damaging your printer.
Removing the filament from the packaging and getting it into the spool is fairly straight forward.Before removing the rubberband, identify the head and the tail tips of the filament. The head will be on the outside of the coil and the tail on the inside. Remove the tail from the rubberband and place it in the spool as shown below being careful to not let go of the coil or the head of the filament. I left the rubberband on the coil and let it hold the head for this.
Once the tail is secure you can lay the coil onto the spool being careful to keep ahold of the head. The coil should lay down nicely given the size of the spool core and allow the filament to lay flay and below the height of the core.
Once the coil is laid down you can then place the head of the filament into one of the sets of holes on the outer edge to hold it. It goes out from the inside and then comes back in as shown below.
Now, because of the way the coil is being held and the shape of the spool the filament should be held in place nicely at the moment allowing you to easily attach the other side of the spool without too much fiddling or concern for the filament coming undone.
And there you have it, you're ready to roll...
Feed free to leave us any feedback on the spool either on the Thingiverse page or by contacting us directly at firstname.lastname@example.org