Running without Bowden

[MichaelOToole]

Just realized, I been printing without the bowden tube for a long time (can't remember when or why I removed it).
I use a little piece of tubing to guide the filament entering the chamber from the spool but that's it...

Most videos show a bowden tube even with direct drive, I don't see the need, am I missing something?

 

[weaslus]

The purpose of a reverse bowden, is to keep the path the filament travels the same length no matter where the toolhead is. without one, what i have seen happen in the past is the toolhead can be pulled around during travel moves. As the toolhead nods, the nozzle raises and lowers. This leads to inconsistent first layer, and any other layer for that matter. Keep in mind, a 0.02mm deviation in the height of the nozzle due to pulling on the filament, is a 10% difference in the height of a normal layer.

 

[vinnycordeiro]

Just realized, I been printing without the bowden tube for a long time (can't remember when or why I removed it).
I use a little piece of tubing to guide the filament entering the chamber from the spool but that's it...

Most videos show a bowden tube even with direct drive, I don't see the need, am I missing something?

Filament friction can carve the part of the toolhead where it enters the extruder on a direct drive setup. Don't ask me how I know that...

 

[MichaelOToole]

Don't ask me how I know that...

... That makes perfect sense, will add a small piece of tubing there too, don't thing I need the full ...

 

[3dCase]

I have been running a short piece myself, just entering the filament sensor on top of the orbiter. But reading the comment of @weaslus , I realise this is a very good point. I will install a longer piece just to see if this accounts for some eratic layer lines I am sometimes seeing.