Boring MasterSpool

Design based on RichRap MasterSpool V4.
I really like many of MasterSpool idea and features of V4 spool, but it takes a while to print and I believe it could use less material and print time. Visual also looks a little bit too interesting for a spool. And I hate that the zip tie slots do not align, when screwed together.
Other solutions do not use threads, that I like about master spool, also there should be a place to attach sticker with filament data.

Things I like about my version:
* looks boring
* needs less time and material, 90mm/s, 0,3mm layer (check print settings) requires in total 8h and 170g of material
* Thread is really tight
* Zip tie slots almost perfect match
* Simple structure and design, easy for me to edit original files
* No writings on walls
* From original design filament end slots in one wall, but 3 of them

What I do not like - zip ties catch, when screwing parts together.

Most basic dimensions are almost the same as original MasterSpool V4, wor