While I was looking for MasterSpool compatible filaments I found the wonderful simplistic SlantSpool design by Slant3D: https://www.thingiverse.com/thing:2850604 This spool prints super easy, faster than the original MasterSpool (https://www.thingiverse.com/thing:2769823) and uses less raw filament. There’s only one part in the design you have to print twice. The two halfs of the spool connect with a simple latching system. Unfortunately the SlantSpool is designed for 1 kg refill coils so the 850 g refill coils available in Europe don’t work well on it.
The CarbonoidSpool is a hybrid of MasterSpool and SlantSpool. It uses the same latching system like the SlantSpool (which I had to clone in Fusion360 because only the STL files are available). Every spool half has 6 filament attachment points for a total of 12! per CarbonoidSpool. It works with 1.75 and 3 mm filament. There’s also a place for the sticker that comes with the filament refills to label the spool properly. CarbonoidSpool is designed for 850 g refill coils. I also made a bigger version for 1 kg refill coils.
Sliced with Simplify3D 4.0 and printed with PLA filament on a Carbonoid D1 Delta 3D Printer. 100 mm/s max. printing speed and 200 mm/s travel speed.
One half
Build time: 4 hours 11 minutes
Plastic weight: 115 g (0.25 lb)
Total
Build time: 8 hours 22 minutes
Plastic weight: 230 g (0.50 lb)
One half
Build time: 4 hours 42 minutes
Plastic weight: 128 g (0.28 lb)
Total Build time: 9 hours 24 minutes Plastic weight: 256 g (0.56 lb)
One half
Build time: 4 hours 27 minutes
Plastic weight: 124 g (0.27 lb)
Total
Build time: 8 hours 54 minutes
Plastic weight: 248.00 g (0.54 lb)
Part A
Build time: 6 hours 28 minutes
Plastic weight: 185 g (0.40 lb)
Part B
Build time: 3 hours 48 minutes
Plastic weight: 102 g (0.23 lb)
Total
Build time: 10 hours 16 minutes
Plastic weight: 287 g (0.63 lb)