Drybox Filament Pass-Through

Last crawled date: 4 years, 1 month ago

Yet another filament pass-through
Update 09.10.2019 - Changed inner diameter of PTFE Tube Cap to 4,2mm for a tighter fit on PTFE tube
I've created a filament pass-through that feeds the filament from inside the drybox into a PTFE tube.
Printed Parts:
Outer Feeder - PTFE tube is guided through the PTFE connector fitting to the Inner Feeder
Inner Feeder - two types:
Type 1 consists of the Inner Feeder and has an outer thread to screw the Inner Feeder Cap on - offers the possibility to use a sponge on the filament
Type 2 - if you don't need the sponge, you can directly feed the filament through the filament cutout of the Inner Feeder into the PTFE tube - no cap needed

PTFE Tube Cap - to seal a pass-through that is currently not in use.
Needed Parts (for one pass-through assembly):
PTFE tube (4mm OD, 2mm ID)
1x PC4 PTFE push-in connector fitting
2x Socket Head Cap (Allen) Screws M4 (length as you need)
2x M4 nuts
optional: piece of sponge
Instructions:
Needed drill holes:
4,5mm for the outer holes - here the two M4 screws will be screwed through
6mm for the middle hole - here the PTFE tube will go through, the bigger diameter of the drill hole will ease the alignment of Outer and Inner Feeder parts

Press the M4 nuts in the relevant spots of Inner Feeder
Screw Inner and Outer Feeder parts together
Outer Feeder: Gently screw the PTFE connector fitting in - as there is no tapered thread in Fusion 360 available for this type of thread, I added some space to the outer feeder inner-thread, so that the PTFE connector can't break the Outer Feeder. Gently there, otherwise you'll ruin the inner thread.
Push the PTFE tube through the PTFE connector fitting and the Outer Feeder until it stops at the end of the PTFE Tube guide of the Inner Feeder.
If you're using type 2 of the Inner Feeder - congrats, that's it. Push the filament through Inner Feeder filament hole into the PTFE tube.
In case you're using type 1 of the Inner Feeder, push the filament through the filament cutout of the Inner Feeder Cap.
Next, stick the filament through a piece of sponge (to remove dust/dirt or lubricate the filament) prior to push it through the Inner Feeder filament hole.
Screw the Inner Feeder Cap on the Inner Feeder - that's it.

Any comments and suggestions for improvements appreciated ;-)
Feel free to remix, Fusion 360 files are included in the download.