gr5

It depends what country you live in. If you want the best quality and you are in USA get colorfab from printedsolid.com.

The horrible "machine gun" noise happens when the stepper "skips" steps. It's a magnetic thing and although it sounds horrible your printer should be fine. All the mechanical parts are stronger than the maximum force from the steppers. If you power off and one axis is stuck then you have a serious mechanical problem. I've seen this when sugar water, candy, glue, glue stick, or hair spray gets on the shafts but it could be many causes. I recommend you start taking it all apart. Loosen the 4 pulleys for the bad axis. Completely pop out the two shafts that go through the head and put the head aside somewhere. Try to figure out if a shaft won't turn or more likely if one or two blocks won't slide along one of the outer shafts in the gantry. It could be as simple as LED wiring caught in the belt/pulley system. If you printer is very new, you could try warranty service with your reseller but this printer is meant to be taken apart somewhat. Certainly the gantry isn't too hard. If you take apart one of the 4 slider blocks however be very very careful. Those are easily destroyed (replacements are very cheap but who wants a "down" printer while waiting for replacement). So pry those open very gently.

What I see in your photos I've seen before. It can be caused because the head is too far from the glass (the glass can be tilted such that one corner is higher) or it could be oil on the glass or a combination of head too far plus other factors. You shouldn't have any problems at all with this kind of thing. Here is a video that explains how to make your filament stick like hell to the glass. It's a long video but it is packed full of valuable information, insight and *why* you have to do what I recommend:

Oh. That's a problem. I put my printer into dev mode when it was just a few days old and it has been there since. It's been a few years.

There is discussion on how to set the temperature of either core here: Read particularly posts by robinmdh Note that your printer needs to be in developer mode and you need to ssh to the printer using username/password ultimaker/ultimaker.

The bits of pva all over the place is 100% normal. Unfortunately. and the tail. However you should be using the default settings which include "horizontal expansion" set to 3mm. And I don't think you are using that. I find it a bit dangerous to have pva start and stop like it does in your print but if you increase horiztontal expansion then pva will have a path through itself down to the glass. If you don't have a path down to the glass then you have pva sitting on top of pla which works but not as well. Anyway this particular part does not benefit from pva as much as some parts do that have much larger, more serious overhangs. Like say a boat propeller would have. A boat propeller benefits greatly from pva. A totem pole benefits also but not as much. But, yeah, pva is kind of a pain. It doesn't behave as well as PLA. PLA sticks to itself when still liquid. Like mucus or snot. PVA not so much - more like cement. Or peanut butter. When it's wet it can hardly hold it's own weight. One of the results is bits of pva chunks everywhere.

gcode is easier to read than you might think at first. Use a simple text editor and search for "time_elapsed". You'll see the Z height and I think maybe the layer number within a few lines of this line.

My first thought was also that you have "initial layer horizontal expansion" set to something greater than zero. I usually set that to a *negative* value to get rid of elephants foot. Setting it to a positive value will just make the foot worse.

First thing to do is decide if it's the feeder or not. Best way to do that is to make sure it can pull about 5kg of force. Put the filament half way down the bowden and hang 2-4kg of weight on the filament and then do "move filament" from the menu. CAUSES FOR UNDEREXTRUSION ON UM3 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. Note that your "print speed" may be 40mm/sec but it may be printing infill at 80mm/sec so CHECK ALL SPEEDS. 2) Line Width larger than nozzle. In cura 3.X search in settings for all line widths. If any of them are larger than the nozzle diameter this can cause underextrusion. There are 8 of these in cura 3.2.1. 3) Curved filament at end of spool - if you are past half way on spool, try a fresh spool as a test. 4) curved angle feeding into feeder - put the filament on the floor -makes a MASSIVE difference. 5) Bad core. Try a different core. It could be clogged, or something more complex like the temp sensor in the core. 5a) clogged nozzle - the number one most suspected problem of course. Sometimes a grain of sand gets in there but that's more obvious (it just won't print). Atomic method (cold pull) is the cure - from the menu do a few cold pulls. The result should be filament that is the exact shape of the interior of the nozzle including the tiny passage to the tip of the nozzle. If it doesn't look like that you need to pull at a colder temperature. You can do it manually instead of through the menu if it's not working right but learn through the menu initially. 95C is roughly the correct "cold" temperature for PLA. Higher temps for other filaments. Simpler cold pull (3dsolex cores only - doesn't work on ultimaker cores because you can't remove the nozzle): https://www.youtube.com/watch?v=u07m3HTNyEg 5b) 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 6) feeder spring issues - too tight, too loose. You want the tension such that you can clearly see the diamond pattern biting into the filament. You want to see at least 2 columns of diamonds. 4 columns is too much. You usually want the tension in the center. 7) Other feeder issues, one of the nuts holding UM2 and UM3 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. ? 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 8b) 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 wedgebot (link below) helps you feel this with your hand by sliding the filament through the bowden a bit to see if it is stuck. https://www.youmagine.com/designs/wedgebot-for-ultimaker2 9) Extruder mis calibrated. Maybe you changed equipment or a wire fell off. Try commanding the filament to move exactly 100mm and then measureing with a ruler that it moved 100mm within 10% accuracy. If not adjust the steps/mm (this is done by editing a json file on the UM3). 10) Z axis steps/mm. it's easier than you might think to double or half the Z axis movement as there is a jumper on the circuit board that can be added or removed. If the Z axis is moving 2X you will get 50% underextrusion. Your parts will also be 2X as tall. 11) Crimped bowden. At least one person had an issue where the bowden was crimped a bit too much at the feeder end 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. Similar to 8b above - use the wedgebot to feel how much friction there is in the bowden. 12) Worn Bowden. After a lot of printing (or a little printing with abrasive filaments) the bowden resistance can be significant. It's easy to test by removing it completely from the machine and inserting some filament through it while one person holds it in the U shape. Preferably insert filament that has the pattern from the feeder and fight the movement by applying 2kg force on both ends at the same time and then seeing how much harder you have to push it on top of 1kg force. UM2 feeders can push with 5kg force. UM3 can push quite a bit more. 5kg is plenty. 13) 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. This shouldn't be a problem on the UM3 which has very good quality control but try a different core. 14) 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. 15) 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 - there is a temp sensor built into the driver chip. The solution from Ultimaker for the um2 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. This doesn't seem to be a problem on UM3 even though it's the exact same circuitry but they lowered the current in the firmware. But it's worth considering if air temp is 30C or hotter. It would probably happen only after printing for a while (air heats up slowly under the printer). 16) third fan broken. This tends to cause complete non-extrusion part way through a print. In the door of the head. You can hear it come on when cores get above 40C. 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. 17) Spiralize/vase mode. This is a rarely used feature of Cura but you might have left it on by accident? In this mode the wall of your part is printed in a single pass. So if you have a .4mm core and the wall is .8mm thick it will try to over extrude by 2X. This is difficult to do and may instead lead to underextrusion. 18) too many retractions (this causes complete failure) - if you have too many retractions on the same piece of filament you can grind it to dust. 10 is usually safe. 20 is in the danger zone. 50 should guarantee failure. You can tell cura to limit retractions to 10 per a given spot of filament. Do this by setting "maximum retration count" to 10 and "minimum extrusion distance" to your retraction distance (4.5mm for UM2 and 6.5 for UM3). 19) Brittle filament. Espciallty with older PLA but even brand new pla can do this. If you unspool some (for example if it's in the bowden) for many hours (e.g. 10 hours) it can get extremely brittle and it can snap off into multiple pieces in the bowden. It's not obvious if you don't look for this. Then it starts printing just fine and at some point one of those pieces reaches the print head and gets hung up somewhere and the printer suddenly stops extruding for now apparent reason. This usually happens within the first meter of filament - once you get to printing the filament that was recently on the spool it should be fine from then on. 20) The "plus" feeder can have an issue where the filament doesn't sit properly for one print and it permanently damages the arm inside the feeder as shown by this photo - the hole is ground down asymetrically: http://gr5.org/plus_feeder_issue.jpg

It's a great printer with that heated bed. It's more important to know what you want to do with it. If you really want to print Nylon or other higher temp material then covering the sides, front and top is a must. If you want dual filament printing then look at the mark2 project on this forum (use google to search for mark2 within the ultimaker.com domain). But really instead of concentrating on the printer, find some nice projects. Look for needs. Maybe a better soap dish, or a replacement knob. Walk around your house or work or church or whatever looking for needs. Then think about solutions. Then think about the printer as the last step.

If you have a volt meter, measure the resistance on all your cores on the left two pads. They should measure I believe around 24 ohms. If it's much higher resistance for one core then you may have one bad core. If they all measure the same then the problem is with your printer. There is a connector in the top of the print head - remove the two very long screws in the back of the print head and then you can remove the rear half of the top cover. Inside is a connector. Try pushing it back down. Then try heating just one core (while it's all apart) and time it and you may find it heats much faster.

I don't know the answer. Maybe someone else does. But what filament are you printing? PLA?

UM seems to recommend no prime tower. It works pretty well without it. I personally like the prime tower for most prints with pva but I know many who get great results without it. The biggest problem is it might fall over. So if it's a print taller than 5cm make the tower bigger and also move it away from the corner (where parts don't stick so well because the glass tends to bend down - not a problem on S5 with multi-point leveling).

In general, more fan is better with pla. But an asymmetrical fan situation will create asymmetrical results.

I'm not sure what you are asking. You have to download and install Cura which will take your model and slice it to create a ufp file. A ufp file is really a zip file (renamed to ufp I think) that contains the gcode and also a picture of what your part is supposed to look like. Or you can just print over the network if you have the printer hooked up to your network. But in either case you need cura to create the ufp file.