Yet another PTFE Tube Cap with Filament Catch and Retainer

Yet another PTFE Tube Cap with Filament Catch and Retainer 
 

A simple cap that seals the end of 4-mm PTFE tubes from humidity, and at the same time prevents the filament from sliding back into the tube. Ideal for use with a filament drybox!

This is a re-design (not a remix) of the PTFE Tube cap with filament catch by Wilko.

I really like his idea of a cap with two conical parts where: 

• the innermost cone catches the filament,
• the outer cone seals the PTFE tube.

However, for some strange reason the prints from his files would not work with my 1.6 mm filament nor my 4-mm PTFE tube.

Since this is a pretty straightforward design, I simply re-designed the whole part (with different angles and lengths) in FreeCAD. At the same time, I included the idea of the retaining strap by ltowe. 

Note: This is designed for specific dimensions. It will not work properly unless you have:

• filament with 1.6 mm OD and
• PTFE tube with 4.0 mm OD

Printing

I printed most of these in PLA. Even at 0.2 mm layer height, they print in less than 10 min anyway  😎

If you print the version with the retainer strip, you may want to use a low layer height (0.2 mm or less) for the first few layers, otherwise the retainer strip may break too easily. 

Sources

I'm sharing my FreeCAD source under the same license as these print files: CC-BY-SA.