I designed this spool specifically for the Laywoo-D3 filaments. This one is actually printed in the Laywoo-D3 filament. Its a little bendy, and I suggest printing in either ABS or PLA.
I also designed this to be printable on an UP printer (140x140mm) and with no support.
Print out one hub and 3 spool arms. They are adjustable for either 3mm rolls or 1.75mm rolls. Fasten an 8mm M3 screw/bolt from the back of the hub. There are provisions for two bolts if required.
The centre hub is 30mm in diameter.