Nozzle Diameter

[Merrick362]

What is the recommended Nozzle diameter? Slicing with a 0.8mm nozzle leaves walls 1 layer thick in many places.

[mza1979m]

Use 0.4mm nozzle, along with the extrusion width settings supplied by Glia (below). I'm sure you should also be able to use 0.5mm and 0.6mm nozzle.

Default extrusion width: 0.5
First layer: 0.42
Perimeters: 0.5
External perimeters: 0.6
Infill: 0.5
Solid infill: 0.5
Top solid infill: 0.45

[Paulhurst20000]

I'm printing with the Cura slicer and I can confirm the settings above for me work really well. I tried various layers /etc but best prints (no fusing where the opening comes together) are using the above settings. On the AdimLab Pro 3D, at 40mm/s print speed it's 2h10m per frame

[mza1979m]

Wow, why does it take so long to print each one? Are you printing version 2? It takes me 42 minutes to print each one at 60mm/s & 0.3mm height (as suggested), with PETG, although I modified the settings heavily to optimize print speed without sacrificing quality and functionality. I'm working on bringing it down to less than 30 minutes, mostly by increasing speed, gradually. But even if left at default, it should be around 1 hour.

[Paulhurst20000]

I was slicing at 40mm/s (new printer to me haven't tried higher speeds). If I slice at 60mm/s Cura estimates 1h24 mins per frame. Maybe we can share other slicing settings somehow?

[mza1979m]

I've used Cura on occasion, but I use PrusaSlicer 99% of the time, so I can only share my project file associated with that software (link below). The factor that affected print time more than anything else was setting infill to 0%, and instead printing the entire part with perimeters (thereby simulating concentric infill where required). Perimeters print much faster than rectilinear/grid infill. I also got rid of useless gap fills that consumed so much time due to so many retractions and extra moves, but I used modifiers to force gap fills in areas that were necessary. Also, as I mentioned somewhere else, I beefed up the center part that goes directly against the forehead as it was prone to breakage, and fixed a couple broken linkages in the design. There's a link to the new STL below if anyone's interested.

Project file: https://drive.google.com/open?id=1Q3UBnA-uA0Q6aWHgzpQQe5wa6BwWVW7S
STL file: https://drive.google.com/open?id=1R4scUgxnPVWTPM47eICsGwnkF5sIscjp

[pokono]

If there is an interest I could develop the profile for a 0.6 nozzle. Bigger than that I don't think there would be a benefit but 0.6 could speed up the print a lot. Let me know, I have a decent experience printing for manufacturing with different size nozzles. (Prusa Mk3S)

[mza1979m]

@pokono correct me if I'm wrong, but for this particular design, I don't see the benefit of increasing the nozzle size, because the walls are only 1mm thick. So whether printing with 0.4, 0.5 or 0.6, you still have to print 2 shells to get the 1mm wall thickness, which would take exact the same length of time as a smaller nozzle. I do see benefit in using a nozzle that is 0.8mm and up, however, because you can print a 1mm thick wall with 1 pass, and that would definitely be quicker.

[pokono]

@mza1979m It's a good point, I have available a few sizes to do a few tests. Let me take a look tomorrow and I'll see what the numbers are! I'll keep you posted.

[pokono]

I took a look.

0.4 mm -> 129 minutes.
0.6 mm -> 98 minutes.
1.0 mm -> 76 minutes.

I would say it's worth exploring more.

[mza1979m]

I suppose it depends on layer height. With a 0.4mm nozzle, the maximum layer you can have is 0.32mm. But with a 0.6mm nozzle, the maximum layer height you can have is 0.48. So I suppose in that regard, it would certainly speed up the print (at the cost of quality). Also, it's possible that an increase in nozzle diameter is eliminating some of the useless gap fills and infills a smaller nozzle wastes time on.

The settings you set are the most important speed determining factor. I use a 0.4mm nozzle and I print 2 shields in 70 minutes (35 minutes per shield) without sacrificing quality or strength. The most important factors in the slicing settings are controlling infills and gap fills by using modifiers (set infills to 0% and gap fills to 0 speed, but use modifiers to infill/gap fill only important areas). Optimal acceleration settings and speeds will also affect print speed but not as much.