sean-stein

Hello, after issues with extrusion especially with PLA, I decided to overhaul our Ultimaker². Since I gathered a lot of information on this forum, more or less spread, I decided to sum it up in one post. Used a modified Version of the e3d Mount, changed it to take the bowden, as I'd ordered the direct drive version by mistake. Hotend uses the PT100 heatblock, just used an extra 12V Wallwart for the fan (ultimaker board offers 5V for this, more elegant would be a 30mm 5V fan). As the Extruder Stepper was loosing steps a lot, I used this as an inspiration, replacing the belt with gears, resulting in a 1 : 2.625 ratio edit: didn't read to the end of thread where a version with gears is already posted. Modified the firmware, as described elsewhere: downloaded from github ultimaker2marlin used Arduino 1.0.3 modified arduino-1.0.3/libraries/Wire/utility/twi.c , /* commented out */ everything after SIGNAL(TWI_vect) close to the bottom and was able to compile Firmware Modifications: HEATER_0_MAXTEMP to 350, e3d + PT100 should easily cope with that Kp: Ki: Kd: changed according to what a M303 S210 C10 command gave me (tune to 210° by heating up 10 times) INVERT_E0_DIR to true, as the gears change direction X_MAX_POS and Y_MAX_Pos minus 15, so the mount doesn't crash into case DEFAULT_AXIS_STEPS_PER_UNIT to 282 * 2.625 (740.25) to make up for the gear (8:21 teeth) First test Print went ok, looks rough, but printed at 60mm/s without a fan. no filament slipping or loosing steps, which would have been unthinkable before. Only thing that didn't work out is the steps per mm for the extruder, hat to set flow to 263% to compensate for the gears, if anyone has a tip on that? edit: steps per mm apparently stored in EEPROM, M92 E740.25 followd by M500 worked. Seems to do the trick so far, just read about the ultimaker²+ upgrade kit some days ago, would have probably gone for that if it were already available.

hm, still having the issue with multiplier down to 0.4 for best result. There is no apparent way to change microstepping on the board individually, it seems there is an over-all jumper between 8x and 16x. In my case only the extruder seems affected, so that doesn't lead anywhere? One way to reduce jamming was turning the cooling fans off, it seemed the sheet-metall is bent so some of the air gets pumped towards the heater. We bent the metal a little, since it was crashing into the main frame when homing. Guess its the problems that come with owning probably one of the first production batch machines, but still utterly annoying considering all the time and money going in adjustments/nozzle exchanges when I've seen and worked with other machines doing quite fine. Anyhow, I'd be glad to find any hints in making this machine more predictable.

Thanks for your reply. Yes, the teflon part was replaced along with the nozzle. I see how a worn down teflon bit can cause extrusion problems, but it doesn't explain why the printers material flow is so off in the default setup?

After using an ultimaker ² for over a year, I still having problems getting reliable prints in good quality. It seems this is mostly related to the extruder setup. It has a new nozzle, the extruder spring is set to least tension. Frimware has been updated regularly. I suspect something on the board is wrong, maybe stepperdriver jumpered wrong, resulting in less microstepping? With the default settings it extrudes way too much material, putting too much stress on the extruder. A callibration box comes out with 1.1mm walls, when they should be 0.4. As a result I tuned down the material flow to 37% to achieve 0.4mm, as seen here: This resulted in prints coming out nice, yet it still tends to start underextruding on longer prints. Since the flow is off with the dafault settings I suspect something wrong in firmware/electronics. Has anybody experienced similar issues or has suggestions/tips to this?

Thank You for your answers, sorry for not being very responsive the last days. By infill, do you mean 'fill density' or 'infill overlap'? I usually use a fill density around 30%, as there seems to be a problem bridging bigger gaps when closing the top, as discribed above. Went down a bit with 'infill overlap', currently at 12%, maybe thats the way to go. uploaded some pics illustrating the problems discribed above: Problems with surfaces: Infill thicker on intersections, stringy in between:

Hello, though I'm able to produce usable prints, I can't seem to get the print-quality on my ultimaker² right. Apart from the default settings, I've played with a lot of settings and followed different calibration-guides, but to no avail. From what I've observed, it seems the string of molten filament that comes out of the nozzle is too thick compared to what comes out of other 0.4 hot-ends I've seen. Reducing the infill doesn't work though, the amount seems right. As a result, it tends to 'smudge' on edges, making a mess of details. And the infill doesn't come out as lines with a more or less constant diameter, but as thin strings and a lump on the intersection. I'm sure this machine is capable of more- what's going wrong? I'd upload some pictures, is that possible on this forum, or do i need a external file hoster?

Thanks for Your Replies, I'll go with multiple Cura versions, as they don't interfere with each other.

Hello, I've been using Cura for a while with a RepRap. Now we've aquired a wonderful Ultimaker 2 and I'm confronted whith some things I'm not sure how to go about: The Ultimaker 2 prints multiple parts one after another, which is good for quality, but bad if you want to pack the print bed with lots of smaller parts, as it limits the packing density. Am I just missing an option? The current Cura version (14.1) which we're using also has a different support material stile, which might have its benefits but is a pain to get rid of. Is ther an option or workaround for the old meander stile?