MasterSpool Coupler for Das Filament Spools

**Update 17/2/2018:**

I finally received my filament refill from Das Filament today but unfortunately it didn't work. As it turns out without cutting the tie wraps first the filament doesn't seem to fit the spool half even *without* the coupler. This means that the idea of reusing old Das Filament spools by cutting them in half in general, is probably not going to work.

Fortunately, a few days ago Das Filament also released [their own design](https://www.thingiverse.com/thing:2791930) for