Filament Dryer Ikea Samla 22L (4 spools)

This model holds 4 spools which have maximum height of 71mm, so for example Sunlu, Jayo, Kingroon. Smaller 0.5kg should holds 8, but only 4 would spin independently. 

Another thing that distinct this design from others is that idlers have whole 71mm of usable idler shaft surface so that different spools can spin on top of it, unfortunately many other designs have bearings without this shaft and in fixed space, because of that only certain spools that matches those distances can spin. 

Project consist of two main components base with idlers and ptfe holders, which design gives option to quickly change tubes with filament.

BOM: 

Metal parts section

- Base:

• 12x  M3x12 screws
• 12x  M3 nuts (preferably nylock)
• 12x  M3 washers
• 16x  608rs or 608zz bearings 
• 2x  M8 threaded rod 345mm
• 4x  M8 nut

- Front bowden tube holders:

• 12x  M3x12 screws
• 12x  M3 nuts (preferably nylock)
• 12x  M3 washers
• 4x  PTFE holders that passes through tube with either M6 or M8 thread.

Total of 24 for each M3x12 screws, M3 washers and M3 nuts, M8 790mm (cut from 1m length) threaded rod and 4x M8 nuts for whole project. 

Plastics:

• 8x idlers
• 6x distance for bearings
• 4x corner brackets
• 4x corner brackets base
• 4x each pieces of front tube holders (p1, p2, p3, p4)
• 4x at least of tube holders, keys or combination of those

Tips for printing: 

No supports needed on any model.
Recommended materials: PETG, ABS, ASA
Not recommended PLA due to material creep, but do what you want - no one checks that ;)

Remember to duplicate and mirror corner parts during slicing. 

Correct orientation of corner brackets: 

Tips for assembly: 

Assemble first above part with idlers, starting from one corner; add nut to threaded rod and then plastic corner. Next add bearing, slice in first idler, then another bearing and remember to put distances between 608 bearings to ensure no friction contact between idlers, do that to all 4 and then last corner, m8 nut and other end corner plastic part. 
 

With those idler holders assembled, next thing is to do the holes in samla box corners. First add corner base (smaller part on the bottom of the feet) as a guide and then drill through holes (for 3mm screws) in box itself. Three of those M3 screws should hold base and corner firmly.
 

When starting to assemble quickswap ptfe holders it is recommended to first do 4 holes (3mm) at the same level, place each hole somewhere in the midle of idler (middle of where spool will be) and lower in space between idlers and base - look at the picture for reference (it is that way so forces that pull filament also pulls spool downside, so that it cant move or fall from place and can spin easily. Then assemble the 4 parts (one inside and three on the outside of the box) by one of 3 corners (top prefferably). Then assebled you can drill rest of holes (i recommend do one hole, add screw and tighten it, then go to next one). 

Process is a little involved, took me more than 2hrs to finish assembly, but it works like a charm, so if you want one i really recommend this design.