@Phil O @Hayfield @Phil G
Hi Phil,
I have spent today trying various changed settings on the Neptune 3 Plus. I want to get results matching what I've been getting on the Neptune 2 Pro. Given that the 3 has a direct-drive extruder, you would think it should be better regardless. But it isn't, primarily I think because it has a poor retraction capability with a maximum retraction speed of only 25mm/sec. Both the Neptune 2 and the little Kingroon have much snappier extruders.
The result last night was disappointing, with far more stringing in the sockets than I'd like. Reducing the temperature to 180degC made it worse rather than better, contrary to general 3D thinking.
It seemed to me that with a slow retraction speed, the nozzle pressure might reduce more quickly if the polymer was more fluid, i.e. at a higher temperature, rather than lower. Then to prevent oozing it might help if the underlying print was cooler, i.e. reduce the bed temperature.
So I have ended up using these settings, and the latest print is much improved. A scrub with a nailbrush removed almost all of the fine stringing, and a quick wet sanding removed most of the remaining rough surface bits:
initial layer nozzle temp: 205degC (same as before)
initial layer bed temp: 60degC (same as before)
remaining print nozzle temp: 190degC
remaining print bed temp: 40degC
I'm using the shiny back surface of the dreaded PEI textured build plate. It works quite well, although needing rather more glue-stick than a glass bed -- which I would much prefer, but won't work on the Neptune 3.
All the dimensions are good, and the clip-fit chairs snap in nicely, and easily push through any remaining slight stringing in the socket.
So I think I'm getting there, and it's worth it to have the bigger 330mm x 330mm (13" x13") build area.
I will post an updated Cura profile tomorrow.
cheers,
Martin.