Hi all
A higher nozzle diameter has the benefit of being able to print faster due to to bigger layer width. There is a tradeoff, you’ll have to lower print speed and/or raise temperature to maintain proper layer adhesion. That means that there is an optimal nozzle size for a given print speed/temperature combination. You also don’t want temperature too high because it will burn/degrade your filament.
In my experience layer adhesion is quite poor with a nozzle of 0.8mm and it also prevents you from printing finer details (gear teeth for example). The tradeoff versus a 0.4mm nozzle doesn’t seem worth it especially if you print overnight.
What are your experiences?
I haven’t experienced layer adhesion dropping with higher nozzle sizes. Are you setting volumetric flow rate limits? If you don’t limit the volumetric flow rate, and try to run higher nozzle diameters at the same speed as smaller ones (especially with greater layer heights), then this could cause that issue, because you’re extruding material that isn’t adequately melted. But in general, nozzle diameter and layer adhesion shouldn’t be closely related.
Minimum feature size, on the other hand, is definitely related, and is indeed the main reason you might want a small nozzle or low layer height.