At home I have a Printrbot Simple Metal and a MendelMax 3. At work I’ve been put in charge of a Makerbot Replicator 2 and 2X. They’re about 3 or 4 years old, out of warranty, and have no support contract w/ Makerbot. All feelings about open-source aside, these are what I have to work with. From what I’m told, the 2X has always sucked. Successful print yield rate on it’s best day is about 50%, and that’s only for small, 30-minute-or-less prints. I’ve replaced the nozzles, installed sailfish, and cleaned it as best as I know how multiple times — enough to be able to field strip and reassemble the extruder and hot end blindfolded. I’ve tried an exhaustive combination of print temperatures, speeds, extrusion multipliers, and a variety of filament brands, but the problem persists: Prints start off strong, but the nozzle clogs somewhere mid-print. Usually not at the same place. The exception to this is the benchy. Prints will start off stellar but then clog when it gets mid-way up the bridge walls, where layer extrusion time is minimal and movement time is at it’s max, almost every single time. The multiple spools of filament I’ve tried (a combination of MakerBot, Hatchbox, and Inland) seem to be of a consistent diameter. In fact, each spool I’ve tried will work flawlessly on the MM3 — and on the PBSM and R2 so long as it’s not something like ABS that needs a heated bed. I’ve been told that the problem is a design flaw in the heat zone somewhere inside the hot end. Am I screwed? I’m not above replacing the hot end all together, but if this really is due to a design flaw then I certainly don’t want to replace it with the same flawed parts it already has.To be exact, when I say “exhaustive combination”, I mean the equivalent of the following:for (t=min_recommended_print_temp – 10; t < max_recommended_print_temp + 10; t+=5) for (s=10; s < 60; s+=5) for (e=0.9; e < 1.1; e+=0.2) for (attempt = 1; attempt < 3; attempt++) print stuff( temp = t, speed = s, extrusion multiplier = e) It took me about 2.5 weeks to walk through the above settings, keeping a meticulous record of each attempt and it's outcome. The printer sucked on all settings. The very best I could get was one good print in three attempts for the model of the benchy bridge walls. (The above test was performed with just the bridge walls, not the entire boat, b/c that seemed to be where the printer screwed up the most.) But after some success, results would prove inconsistent when I would try three more prints at the same settings.Maybe there's something really stupid that I've overlooked, something that a fresh pair of eyes from r/3DPrinting will see right away. But I've got a 2ft high bucket at my feet that's full of plastic scrap and a mere handful of usable parts, and I'm ready to throw the thing at the wall. I'm sorely tempted to just strip the thing for parts and call it even. http://ift.tt/2cNvyar