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My um2 came default settings for PLA retraction to use 2.5mm. That's not enough. Change that to at least 4.5mm. Someone with a UM2 suggested even more - I think maybe 5.5mm but whatever your retraction is, increase it slightly. 190C and 20mm is very smart. This is a good setting. DO NOT use "default" settings or easy print settings or whatever they are called. Only use expert mode and make sure "retraction" is enabled. Also set the other retraction parameters in expert settings to 0. So minimum extrusion should be 0. Minimum travel should be 0. Otherwise it won't retract at al. Even a minimum extrusion of .1mm translates to 4.9mm of movement if your layer height is .1mm and some of your extrusions for this bracelet look smaller than 5mm. So set these to zero!!!

Many of the old plugins that worked fine for Cura 13.04 and older broke when Cura 13.05 came out. This is because Cura now uses G0 for it's move code when changing height but the older cura used G1 for the move command (they do the same thing in the UM but other printers different). So you need newer versions of all the plugins. For example this one works great: https://github.com/Dim3nsioneer/Cura-Plugins/blob/master/TweakAtZ.3.0.py That one even now takes care of if you are printing many objects in the same build plate (but one at a time). It resets and does the same tweakAtZ on *every* print - not just the first one.

I never use those - even on the first day I got my UM I started playing with all the parameters. There is a relationship between temperature and speed. If you print hot like at 240C you can print fast like at 100-150mm/sec with .2mm layers but you might get a little underextrustion and you won't get quite as good quality and also you will get TONS of stringing. If you print real cold like at 190C you can't print much faster than 30mm/sec but at 20mm/sec I get very very good quality (still talking .2mm layers) and you will get almost zero stringing. If you try to print cold and fast you will get severe underextrusion (lots of pressure in the nozzle) and likely filament grinding and slipping.

The newer firmware heats the bed to 90% before starting to heat the nozzle - this way they supposedly get to temperature at the same time. I'm not sure if the timing is always perfect though.

Yes. And add a drop of thin oil without getting any oil on the knurled bolt: This video from peter is great - start about 50-60 seconds into the video:

Just do it half way between how it was and how it is.

It will always be as loud as a dishwasher which is too loud to sleep by but okay for watching television maybe. Some time when your printer is printing, grab the extruder drive and remove it from the back of the UM (yes, *while* printing). Notice the change in volume of certain pitches. Then re-attach. It gets louder. This part can take away that sound but not the other sounds: http://www.thingiverse.com/thing:53690

I also recommend Drayde remix.

Amazing photo. It could be other things but it sure looks like a Z issue. I would disassemble the Z screw. Check to see if it is straight. Lay the z screw on a flat table and check it carefully by eye.Slide the bed up and down without the z screw. Also see if the z screw lines up perfectly with the coupler.

Why do you print 190C? That's quite cold for PLA. I recommend trying 220C or 240C. Don't be afraid to try a little hotter.

He saved the video in 4 formats. Same video. 4 formats. One of them should work for you. They all worked fine for me.

PM illuminarti about nozzles.

I had to stare at the photos - they are a bit blurry and also dark. But I'm 80% sure this is underextrusion in the walls. Easily fixed - just raise the temp to 240C or lower the speed to 30mm/sec. Try one or both of those first to see if it makes a big difference. If so then what temp and speed were you printing at? You may need to tighten your extruder spring but first lets get it to print better.

So will someone send the recording to Harma?

I like Illuminarti's theory. A lot. It fits with what you see because Cura has the fan off for the first few layers and gradually turns the fan on (it also gradually speeds up the print). This part appears to have no stringing issues - meaning it appears that there isn't much retraction going on. So I would recomend a little more heat and a little less fan. Also since the part is nice and large you might be able to do without the fan. Can you turn fans off or run at 50%? Also raise temp to between 210C and 230C. Those two things (220C and less fan) will probably be enough.

Yay!!! :sad: Warping/shrinking is very complicated. If all you care about is the bottom layers this is very easy to fix. Assuming the part is the robot or larger and you are using the blue PLA that came with the UM2 then 70C bed temp is great. This will keep the lower layers of the robot hot enough that it never becomes solid and so it will be soft. It is also important to keep the fans off for the first 10mm or so. That way the entire lower portion of the robot stays above 55C and 55C is about where that ultimaker blue PLA turns from mush to solid. You can do this in cura advanced "cool" settings. It would be helpful to keep the air also hot so I would consider closing the front of the UM and covering the top with a box but this shouldn't be necessary. In addition, the "brim" feature in cura helps immensely. Also cleaning the glass (with soap and water or alcohol or windex or dish washing soap) and then a thin coat of glue stick. Make sure the glass plate cools to at least 50C before trying to remove the robot because at 55C or warmer you may destroy the robot (distort it). For ABS you need the glass MUCH hotter - I think around 110C maybe?

This seems unlikely but possible. Are you sure you aren't getting MINTEMP or MAXTEMP errors? Is this a um1 or um2? Search the gcode file for M104, M109. e.g. M104 S0 turns off the extruder heater. This is a common problem. The models have extra internal walls or holes in the walls. Experiment with the 4 checkboxes in the "check horrible" section. It's easy to try all 11 combinations of checkboxes to see if you can fix this. If not you have to look at the model in "xray view" instead of slice view and fix any red areas. But usually "fix horrible" can take care of it.

I mean that I can *usually* print on the UM original 190C and 50mm/sec but sometimes it under-extrudes. It's kind of on the edge. It will be minor under-extrusion and the part will be functional but ugly or it will have zero underextrusion and come out quite perfect it's just on the edge. But if all I care about is functionality then I print at 150mm/sec and 240C.

Well next time you are coming by Boston LePaul lets get together and fix your printer.

Well it isn't a problem on *every* UM2. For instance on my UM2 it just barely misses the clip and all is fine. So I think the first few UM2's that were built didn't have this issue. But not only does UM know about this problem - I saw a list of "bugs" they are fixing and this is on their short list.

Please encourage that person to translate to english. I only read the english pages and if you post a question in english you will get a fast response. There probably just aren't enough italian users yet that are nice enough and smart enough to answer all the questions yet. Most of them are probably not reading the forums and are enjoying their printer.

Other people have the same symptoms as you - they upgraded the UM firmware and now the green light comes on but not the front panel. For them the problem was that they loaded the UM1 Marlin firmware into the UM2. When you use the Cura wizard to upgrade the firmware you have to be very careful! You won't break anything but I suggest you re-load the firmware and be extra careful. For example you might want to use the expert menu - that way you can see the file names and choose one that says "um2".

I'm not sure what you mean. Are you clicking on print from the front panel or within cura. You should only be printing from the SD card. When you click print it shows a "progress bar". It doesn't print until the progress bar gets all the way to the right - this is because it is waiting to heat up. I'm not sure what you mean - but on my printer it also prints 2cm to the left.... from the center line. Is that what you mean? 3a: if the filament has retracted more than a little, then before you print, go to the advanced menu where you can extrude some filament until it gets back towards the head again. 3b: clicking is bad but not necessarily super bad. It means you will get underextrusion and not as good quality on your print. But you will still get an "okay" print. To reduce extruder clicking you must print either hotter or slower. Try raising to 240C or dropping your print speed in half. Just try it. You can do it while it is printing - change feedrate to 50% or change nozzle temp to a higher temp. This is a known bug. There's lots of posts about this. I think if you get the latest cura and re-install the firmware this is fixed. There are alternate fixes for now - one is to add a line that says simply "M25" to the end of your gcode file on the sd card before you print it. The bug has to do with Marlin not being able to read the last bit of the gcode including the part where it lowers the bed, turns off the heat. Another known bug. This wizard is for UM Original only. I suspect this will be fixed by ultimaker soon. They will either move the clips or somehow disable this wizard for the UM2. For now - just don't do it. In fact the only time you should ever connect to your UM2 with USB is to upgrade the firmware. Any other time is asking for trouble.

Richard - as Robert already mentioned - I already answered your question. Please read it again.

Nick is right on both counts. Stopping this leak by tightening is not easy. I think you have to do a complete disassembly. Either that or raise the 4 screws, remove heater and temp probe and rotate the whole aluminum block. But it needs to be well over 180C when you do this. Or you can take it apart and put teflon tape in all the threads - the problem isn't with the nozzle threads - it's higher up in the threaded brass tube. Another way to stop this leak is by printing with some abs for a few minutes and then switching back to pla. The ABS will leak out of the cracks, and then cook and boil and blacken and gum up and seal all those leaks. UM used to ship a meter of ABS with every machine and the purpose was to seal up the leaks. But be careful if you tighten with a wrench - brass is not very strong. Your other problem I agree is underextrusion. Try printing a little slower maybe. Or maybe tighten up the spring on your feeder. Or raise the temperature a little bit - maybe to 240C?