Hi,

I mostly print PETG. But PETG sometimes tends to ooze a bit (large travels)...
I was wondering if a 0.25 or 0.3mm nozzle could help.
Hotend = genuine E3D V6, extruder = BMG knockoff (that works great), Bowden tube.
I currently don't have small nozzles (usually I print with 0.4 to 1.2mm nozzles, with an E3D Volcano for large ones).

I'm asking before purchase : is it worth it ? Will a smaller nozzle minimize oozing ?
Of course, a smaller nozzle will rise the back pressure, it could be counter productive.
What about material buildup on small nozzles ? (no problems with 0.4mm ones, as I always slighly underextrude)

Genuine E3D nozzles = 0.25mm
No name nozzles = 0.3mm (most of the time)

Does someone have some experience with 0.25/0.3mm nozzles + PETG ?

I've no adhesion problems. I always use mirror + hairspray.

The question was about clogging and oozing. I created a design were I needed a thin shell, and was getting horrible results with a 0.4mm nozzle and 3 walls (thinest region is 1.2 mm).

I got really good results with a 0.3mm nozzle, 4 walls and linear advance. I now can say there's no problems printing PETG with a 0.3mm nozzle. Next step 0.2mm ?

The project was a geared ring for a underwater DSLR housing + macro lens. The seam is not perfect but good enough (it's just cosmetic), and the whole thing is working like a charm.

I still do not understand why I get good prints with 4x 0.3mm walls and uggly ones with 3x 0.4mm walls... I tried many combinations with the 0.4mm nozzle, with no success. The 0.3mm nozzle gave me the "perfect" print directly !

Here's a (crappy) picture of the thing. diameter = ~85mm, height = 95.5mm

Material : BasicFil PET Black, 230°C/90°C, flow = 95%, 0.16mm layers, 40mm/s, 800mm/s², 12mm/s, full metal E3D V6 with knockoff 0.3mm nozzle, retraction 3mm, linear advance factor = 1.0, sliced with Cura + Arc Welder plugin ; modded Tevo Tornado (mechanical dual Z, BMG extruder, etc.).

Edited 5 time(s). Last edit at 08/07/2021 11:53AM by yet-another-average-joe.