3d_bart

Hello guys. Love the ultimaker, it has been our workhorse for past few months. We do a lot of in-house automotive engineering and this thing is printing prototypes about 50 to 80 hours per week for the past 4 months. We're printing exclusively with PLA, although we did try ABS once. The nozzle seems to be generating a lot of buildup and I'm not sure where it's coming from. Starting last month, the print quality was getting progressively worse. I found myself doing the 'atomic' cleaning method almost every time we needed to print. Not good. We ended up getting couple of replacement nozzles from fbrc8 (thanks for super fast shipping!) and now the printer is well. But I took the old nozzle and scraped the inside of it with a needle and found an incredible amount of junk in it. Below are pictures of what I found. Some of the chunks are huge! No wonder I had to keep unclogging the nozzle almost every time we printed. Some of the degree looks carbonized/charred, some looks gray and flaky. The entire nozzle was completely caked with this stuff. The only thing I can correlate to this massive buildup is using https://shop.ultimaker.com/product/22/PLASilver-Metalliccolor PLA, which we got directly from ultimaker website. The composition of the plastic appears to have specs of glitter like particles. The buildup most closely resembles that material. Anyone had problem with that? I would like to prevent this from happening to the new nozzle in the future. Any tips and tricks?