nuffort

You are good! I found yesterday when I took the hot end apart that the fan had cracked, so I rotated it around to ensure the long thumb-screw rods are going through solid holes. The part is printing now and looks much better already at the higher temp, so I think you are right on about our printing temps. The fan may have been a contributing factor...

Thank you, Illuminarti. I just increased the temp and will let you know the outcome. What is the cubic mm/s range we should shoot for in the future? Do you have any suggested guidelines for temps vs volume of PLA per second? I'm also attaching a new photo of our hot end. There is a little more distance between the heating block and the PEEK than it appeared in the first photo. That said, there is less than there was. We adjusted it after these issues starting happening. Originally, our nozzle was screwed completely into the heater block, and the brass tube was screwed in as far as it could be to contact the nozzle. There were no threads showing on the brass tube, as stipulated in the assembly instructions.

Here is the image of our extruder.

The brand is UltiMachine black 3.0 mm PLA. It is more glossy than it looks in the photo.

Adam and I work together, so I am replying to the question from his original post. The machine is two months old. We have printed numerous successful parts on it for the past two month, including successful large parts. The problem seems to be getting worse. As Adam said, we have tried four different types of PLA. In the print above, we used the following settings: Temp: 195 Speed: 65 Layer height: 0.15 Shell thickness: 0.8 Retraction: on Fill density: 50% 2.9 mm diameter on the filament at 100% flow I will attached a photo of the hot end in the next post. Regarding the questions on the type of PLA. It is the UltiMachine black PLA.