Simple filament spool holder

Yet another filament spool holder...

I was looking for a filament spool holder that fits my needs:

)fits >2kg spools
)still compact
)simple
)yet with ball bearings --> friction test: http://gph.is/2lKmGoh
)and adjustable friction

Considering the huge amount of spool holders here on thingiverse I was quite amazed not to find one that is just perfect for me. So I designed this. Due to it's simpleness it's a bit wobbly but it does the job.

Additional stuff you'll need:

)8mm threa