gr5

3dhubs.org will do this for you!

Heat block to 180C. Get a heat gun and blow on that blob and be very patient. Remove bits at a time. Use tools like toothpicks or popsicle sticks or a screwdriver or pliers. And be patient. it takes a long time. If you dont' have a hot air gun and if this is PLA then a hair dryer will probably also work. You might be lucky and be able to heat the block to 180C and walk away and come back after 30 minutes.

I don't have much to help you - if you print colder you shouldn't care so maybe lower the temp by 15C just to see what happens. Even better go into the TUNE menu and lower the temp 5C at a time while printing and mark with a sharpie where you change the temp to see what works and what doesn't. You probably will also have to slow it down so set feedrate to 50% as an experiment also. Having said that, 8mm retraction is too much! Unless your bowden is 2 meters long, 4mm should be plenty. Is this a bowden printer (if so around 4 to 5mm retraction - if not then around 1-2mm). If you retract so much that air gets into the nozzle then the retraction will cause more problems than help. I'm assuming you have bowden printer - you want to retract enough so the filament at the top of the bowden arc moves from pushing against the inner top of the bowden to resting on the bottom of the arc of the bowden. If the filament actually pulls out of the head at all then that's too much retraction. You just want to relieve the pressure.

Ignore the leveling procedure at this point - it's probably level - you just need to move it closer to the nozzle so turn the 3 screws CCW by a half turn. Even better learn how to make the bottom layer stick like hell - watch my video:

Try the "fix horrible" settings in expert settings. That *might* help. Basically your model is not manifold meaning it has inerior structures or more likely some holes in the outer surface. That's fine for a visual-only model but not fine for something you want to print. Cura doesn't know inside from outside - a human knows instantly that the inside would be roughly the area just above the layer below. But cura doesn't know. If you look at the model in cura xray view it will show your problem spots in red/brown colors. That way you can zoom in and find the missing (or extra) surfaces. Or alternatively there are packages that fix models. Free websites. google "how do I make my STL manifold".

The prusa forum has 70,000 users. I think you should go there. Lots of experts there.

No - I recommend a UM2 if you want to use octoprint. Hopefully some hacker good with software will figure out how to get octoprint onto the UM3 (as it has unix and everything is open source and visible). There is no usb to connect octoprint to. Well there is but you'd have to disconnect the connection between the two computers inside the UM3. And at that point you might as well buy a UM2.

It's possible to program it if you are good with ssh. If you are comfortable with ssh send me an email at gr _at_ gr5.org and I'll send you instructions. Also look at the nozzle itself very carefully. It should have a tiny AA or BB on the nozzle. Or you can just send it back to the reseller where you bought it.

First figure out what is the noisiest thing. Is it fan? (which fan) or XY or E or Z? Usually the 3rd fan can be pretty loud or the extruder is the other likely culprit.

Is this a UM2? What printer is this. If UM2 I bet that 3rd fan on the back of the head isn't spinning - just as geert says. It should be spinning any time the head is above 40C.

So overhangs do this - they get raised edges on the edge that is overhanging air. Even on a mere 45 degree angle. You need to do 2 things: 1) 100% fan. Max fan. Maybe add more fan. this helps quite a bit reducing the raised egdes to a minimum. 2) Make the part stick like hell to the glass. This is probably the only thing left for you to do. You should be able to pick up the printer with that little pikachu. More details in this video - I know it's a long video but it's packed with useful info:

ALWAYS look at your part in cura layer view before trying to print it. There's probably nothing to print. Look at it in xray view also. Post a photo of what it looks like in normal view, xray view, and layer view please.

I make all my holes .5mm larger than desired. Vertical holes. Horizontal holes are fine.

Not in cura 2.*. Maybe in cura 3? but I don't really know. I haven't seen cura 3 yet. So don't wait for it because you might be disappointed (it might not be able to do this either). Certainly S3D does this but it's not free.

No idea. Note that Cura 15 is from 2015 (the start of the version is the year, then month, then day it was released) and cura has had massive rewrites since then so I don't think you'll get much help here. You might want to go back to teh one that worked. Cura 14.* and 15.* are all all quite good and reliable and don't feel like you are missing anything critical just because it's 3 years old. Actually I have one idea - drivers for your graphics card. Try upgrading your graphics card drivers. This fixes many visual issues with Cura.

Before assembling look over the documentation again. The latest documentation (probably about a year old?) is quite good with lots of photographs. I've seen all kinds of mistakes where the printer could still print. Things like aluminum plate on the wrong side of the wood (okay maybe that's impossible, lol), teflon inverted, peek part on the wrong side of the wood part and so on. In particular think about the inner path and make sure everything is flush - for example the nozzle needs to be touching the brass tube I believe (inside the aluminum block). And it's tricky to get the nozzle touching the brass but still flush against the aluminum (for good heat transfer).

What printer are you using?

I'm going to guess he went from 2.6.2 to 2.7. I would try deleting all the old 2.6.2 profile junk and then starting up 2.7 again. Cura 2.* doesn't always upgrade gracefully. If you do this you will lose all your profiles that you saved but it's probably worth it. For windows it's in %appdata%/cura/ - just delete everything in there and it's okay to delete the folder itself. For mac/linux... well give us more info before we give you more info.

There is a minimum part thickness that can print. Typically if the nozzle is .4mm the minimum wall width is around the same I believe with cura 2.7. Try changing ALL the line widths to .3mm for a .4mm nozzle (that's about the minimum you can go down to and still get reasonable quality). Or consider using a .25mm nozzle.

Maybe not related but 250C is a little dangerously hot with ABS. If you leave it at 250C in the nozzle too long (maybe 5 minutes) wihtout printing it turns into a gunk that will clog the nozzle. This is the same consistency as gum that someone chewed for a while and then let get down to room temperature. How old is this UMO? I'm guessing either you put the head together slightly wrong or the teflon part (the white part) has gotten old and is too soft and can expand under inner pressure from the filament. You can test all this by doing a cold pull (google it and restrict searches to ultimaker.com). After the cold pull you can look at the filament shape and should be able to see each piece of the inside of your print head (where nozzle exists, where brass tube is, teflon part, peek part, etc. I'm thinking maybe things aren't flush when screwed together. It's tricky when assembling the head. A photo would help. What can happen is after the print is over if it cools a bit the filament can expand into a section of the print head that is below 100C and get stuck there so it won't go in or out. I could be completely wrong about this diagnosis. It could be the 250C thing. I usually print ABS at 245C and set the fan to the minimum (around 30%). It also helps to enclose the printer somewhat to get the air temp at 35C to 40C. But this has nothing to do with clogging. On work around is of course to remove and re-insert the filament after every print. I know that's not a great solution for you.

They will probably ignore this unless you test in 2.7 which is the latest released version.

Also try slicing with even smaller nozzle size - try setting to 0.13mm nozzle as often the nozzle hole is smaller than the manufacturer claims or can get a layer of something (gunk) on the inner walls. And it's better to set the line width a little too small than a little too big.

Try printing 2 bency's at the same time. This lets one cool while the other prints. @labern any advice? @labern is a "tiny printing expert"

@replikant - underextrusion can be caused by about 30 different things. What kind of printer do you have? Here is my standard list of possible underextrusion causes for UM printers: CAUSES FOR UNDEREXTRUSION AND HOW TO TEST FOR THEM AND REMEDY THEM As far as underextrusion causes - there's just so damn many. none of the issues seem to cause more than 20% of problems so you need to know the top 5 issues to cover 75% of the possibilities and 1/4 people still won't have the right issue. Some of the top issues: 1) Print slower and hotter! Here are top recommended speeds for .2mm layers (twice as fast for .1mm layers) and .4mm nozzle: 20mm/sec at 200C 30mm/sec at 210C 40mm/sec at 225C 50mm/sec at 240C The printer can do double these speeds but with huge difficulty and usually with a loss in part quality due to underextrusion. Different colors print best at quite different temperatures and due to imperfect temp sensors, some printers print 10C cool so use these values as an initial starting guideline and if you are still underextruding try raising the temp. But don't go over 240C with PLA. 2) Shell width confusion. Shell width must be a multiple of nozzle size. For example if nozzle size is .4mm and shell width is 1mm cura will make the printer do 2 passes with .5mm line width which is possible but requires you to slow down much more to make a .5mm line out of a .4mm nozzle. If you really want this then set nozzle size to .5mm so it's clear what you are asking Cura to do for you. 3) Isolator - this is most common if you've printed extra hot (>240C) for a few hours or regular temps (220C) for 500 hours. It gets soft and compresses the filament under pressure. It's the white part touching the heater block. It's very hard to test when not under full pressure (spring and bowden) so sometimes it's best to just replace it. Also if you notice parts of it are very soft (the blacker end where it touches higher heat) then it's too old and needs replacing. 4) Curved filament at end of spool - if you are past half way on spool, try a fresh spool as a test. 5) curved angle feeding into feeder - put the filament on the floor -makes a MASSIVE difference. 6) Head too tight? Bizarrely MANY people loosen the 4 screws on the head by just a bit maybe 1/2 mm and suddenly they can print just fine! Has to do with pressure on the white teflon isolator. 6b) Bowden pushing too hard - for the same reason you don't want the bowden pushing too hard on the isolator. 6c) Spring pushing too hard. Although you want a gap you want as small as possible a gap between teflon isolator and steel isolator nut such that the spring is compressed as little as possible. 7) clogged nozzle - the number one problem of course - even if it seems clear. There can be build up on the inside of the nozzle that only burning with a flame can turn to ash and remove. Sometimes a grain of sand gets in there but that's more obvious (it just won't print). Atomic method (cold pull) helps but occasionally you need to remove the entire heater block/nozzle assembly and use flame. Or soak it in acetone overnight (after removing 90% of the material with cold pull). 8) Temp Sensor bad - even the good ones vary by +/- 5C and bad ones can be any amount off - they usually read high and a working sensor can (rarely) fail high slowly over time. Meaning the sensor thinks you are at 220C but actually you are at 170C. At 170C the plastic is so viscous it can barely get out of the nozzle. You can verify your temp sensor using this simple video at youtube - on you tube search for this: mrZbX-SfftU 9) feeder spring issues - too tight, too loose 10) Other feeder issues, one of the nuts holding machine together often interferes with the feeder motor tilting it enough so that it still works but not very well. Other things that tilt the feeder motor, sleeve misaligned so it doesn't get a good grip. Gunk clogging the mechanism in there. 11) Filament diameter too big - 3mm is too much. 3mm filament is usually 2.85mm nominal or sometimes 2.9mm +/- .05. But some manufacturers (especially in china) make true 3.0mm filament with a tolerance of .1mm which is useless in an Ultimaker. It will print for a few meters and then clog so tight in the bowden you will have to remove the bowden from both ends to get the filament out. Throw that filament in the trash! It will save you weeks of pain 11b) Something wedged in with the filament. I was setting up 5 printers at once and ran filament change on all of them. One was slowly moving the filament through the tube and was almost to the head when I pushed the button and it sped up and ground the filament badly. I didn't think it was a problem and went ahead and printed something but there was a ground up spot followed by a flap of filament that got jammed in the bowden tube. Having the "plus" upgrade or using the IRobertI feeder helps you feel this with your hand by sliding the filament through the bowden a bit to see if it is stuck. 12) Hot weather. If air is above 30C or even possibly 25C, the air temperature combined with the extruder temperature can soften the filament inside the feeder such that it is getting squeezed flat as it passes through the feeder - this is obvious as you can see the problem in the bowden. The fix is to add a desk fan blowing on the back of the printer. Not an issue on the UM2 "plus" series. 13) Crimped bowden. At least one person had an issue where the bowden was crimped a bit too much at the feeder and although the printer worked fine when new it eventually got worse and had underextrusion on random layers. it's easy to pull the bowden out of the feeder end and examine it. 14) Small nozzle. Rumor has it some of the .4mm nozzles are closer to .35mm. Not sure if this is actually true. I'm a bit skeptical but try a .6mm nozzle maybe. 15) CF filament. The knurled sleeve in the extruder can get ground down smooth - particularly from carbon fill. 4 spools of CF will destroy not just nozzles but the knurled sleeve also. Look at it visually where the filament touches the "pyramids". Make sure the pyramids are sharp. 16) Hot feeder driver. I've seen a more recent problem in the forums (>=2015) where people's stepper drivers get too hot - this is mostly a problem with the Z axis but also with the feeder. The high temps means the driver appears to shut down for a well under a second - maybe there is a temp sensor built into the driver chip? The solution from Ultimaker is that they lowered all the currents to their stepper drivers in the newer firmware. Another solution is to remove the cover and use desk fan to get a tiny bit of air movement under there. TinkerMarlin lets you set the currents from the menu system or you can send a gcode to lower the current. Ultimaker lowered the default currents in July of 2015 from 1300ma to 1200ma for X,Y,Z but left extruder at 1250. Other people (I think the support team of a major reseller but I forget) recommend X,Y,Z go down to 1000mA. M907 E1250 Above sets the extruder max current to the default - 1250mA. So try 900mA. This will only change until next power cycle so if you like your new value and want to save it use M500. You can just put these into an otherwise empty gcode file and "print" this and it will change. Or get tinkergnome marlin! You will wonder how you lived without it: https://github.com/TinkerGnome/Ultimaker2Marlin/releases M907 E900 M500 17) third fan broken. This tends to cause complete non-extrusion part way through a print. In the rear of the head for UM2 and the front of the head for UM3. Without this fan several things can go wrong. It can take a while as usually you also need several retractions to carry the heat upwards. There are a few failure mechanisms and I don't understand them all. One of them is probably that the molten PLA spreads out above the teflon and sticks to the metal in a core or fills the gap at the base of the bowden in UM2. Later it cools enough to keep the filament from moving up or down.

apt? install? What? upgrade? I have Ubuntu. I downloaded cura from the UM website and it's a single file. Nothing to install. Nothing to upgrade. Just execute the single file. You probably want to delete everything in the cura folder that has settings from 2.6 to reset things back to zero. Do this when cura is not running and then cura recreates this folder: ~/.local/share/cura