JonGregory

Well, I've made some progress and got much better results - not great, but much better. When I was printing with 0.4mm nozzles (PETG) I often turned the cooling down to zero to get the material to flow together a bit better - it seems that this isn't a great idea when printing with 0.8mm nozzles. Maybe the thermal mass of the fresh layer is a bit greater (although it's the same thickness) anyway, it seems that the nozzle picks up on the layer too easily and causes that frilling effect. Turning up the cooling flow to 75% cured most of the problems. Slowing down the print from 60 to 50mm/s also

Hello all - I've been happily printing stuff for a while now and wanted to print some larger things so swapped the 0.4mm nozzle for a new 0.8mm one. And whilst I expected the print quality to suffer a little, I didn't expect it to dive off a cliff and leave the building. It seems as though the nozzle is over-extruding or over running and pushing the outer wall which then frills out and causes a ridge which is higher than the next layer resulting in a progressively worse clash between the nozzle and part. The only other thing that has changed in my process is the version of Cura (now 4.6) - I'v

I don't have a microscope, but I'll try and get a few shots. What build plate temperature did you set for your PET builds?

I've been running similar tests - I'll send the results when I get a moment. But I've noticed that quite a few of my prints become opaque as soon as the second layer is laid down - it looks like the first layer is laid down with good transparency (when the temperature is low enough to avoid bubbles) - but the nozzles scores this fresh surface as it lays down the second layer, scratching it and making it opaque. Has anyone else noticed that kind of behaviour and found a fix? Cheers