Spool holder and drybox modification for the Prusa XL

This is a filament spool holder and dry box modification that can be attached to the Prusa XL filament holder. The original is from Ondřej Stříteský, can be found here.

This modification of the drybox, has been extended by XL side mounts.
The rear hinge has been removed and replaced with a rotary closure so that you can lift off the lid completely; otherwise it does not fit at the XL side. 
This mount for the XL is not very stable, but for my purposes it is sufficient. If you want, you can create a more stable version; probably the bottom should also be reinforced with the side wall.

Assembly of this filament spool holder is described in this Prusa Blog.

In my experience, the filament in this box stays between two to four weeks, below 30% humidity. 
I always put four spoons of silica gel balls directly into the box  - my spoon is from here.

In my observation, the tpu-seal does not have much effect on the preservation of dry air in the box. So you can use it without seal too.

For changing the silica gel balls I use mini-battery vacuum cleaner, so I can add and remove silica without the balls getting lost. 

The sixth filament spool holder is mixed with a ball-bearing. With this mod, I have created a ball-bearing TPU filament guide from the spool-holder into the housing to the extruder. This allows me to print up to TPU 60A.
I used for the bearing version the hub and nut from Universal Auto-Rewind Spool Holder. You can download them here.

I put all my versions of the upper part online, which differ at the place where the filament is taken out of the box. You can try and test yourself and think about how you want to mount it on the XL. 

This mod is not especially well-designed; it was a quick fix to keep the spools that are on the outside of the XL reasonably dry. 

The connection of the PTFE tubes to the box is from this model.

For assembling, use the screw of the original filament holder and add a washer.

Print Settings:
Profile: 0,20mm SPEED
Infill: 30% Gyroid
Support: I used painting organical support for the nob at the front size (see images)
Seam: I used painting seams an placing it in the back corner to the printer side. Otherwise the print will not look perfect.
Material: PETG Prusament magic black

To notice:
I had some print failures, I guess there is an error in the XL firmware (maybe slicer). The x axis just did an shift of about 50mm to the right side and continuing printing like nothing happened, then it will continue printing in the air. About this reason I printed only one part at once. For my 12 parts, 3 of them failed. If you print this and have the same behavior, pleas leave a comment here, so I know, it is not my printer, which is doing all other prints just fine.