gr5

Can you zoom in and circle what you call "ugly walls"? I really don't know what you mean.

That's the speed of light in mm/minute. It's a problem for most versions of marlin. Change the feedrate speed to 40mm/sec or something reasonable in cura. By default it's set to "zero" which then sets it to the speed of light which should be limited by Marlin but Marlin can't handle numbers that large so it messes up.

In the english version of cura it's "retract" and I don't think you want to mess with that unless you know your printer well. Each type of printer needs different settings. Does the ender3 have a bowden? Is the feeder mounted on the head where the hot end is? Or is the feeder on the other end of a meter long tube? If the feeder is on the head you want very short retraction - typically 1 or 2mm.

Burt, what happens if you choose line width of 0.3, 0.2, 0.1? Eventually it will slice? What is the threshold? Also did you try "print thin walls"?

How are the fans positioned on your printer relative to the good and bad sides? Does the bad side get more cooling? Less cooling?

If you have a powerful computer on your printer, such as a smoothie board or other cell phone processor then you can make this quite small, say 0.1mm, because those tend to have a buffer that can store 100 gcodes at a time so if there are 30 steps going around a rounded corner that should be fine. But if you have an Ultimaker (UMO through S5 models so far) that has Marlin in it or almost any of the other 99% of 3d printers in the world, Marlin only stores 16 future moves at a time and has to be ready to stop by the 16th. So it will print amazingly slow if you lower this to 0.1mm and your model is very high resolution (like, say, yoda). The current value of 0.8 or so, should be fine. It means that minimum line lengths are 0.8mm.

How do you know a relay is clicking off?

That should be fine. With PLA it's actually an advantage for parts to cool down extra. I've seen people print chain mail which is thousands of interlocking chain links. So you can definitely print 15, lol. 🙂

It was probably wobbling around while you were printing. I would consider putting a little bit of support - added in CAD - to keep it from being to wobbly. But I don't understand the question. Um... No culprits? You need to be a little more specific. Maybe circle something? Arrow something?

FYI a 0.4mm nozzle can print a bit smaller - certainly down to 0.35mm line width is fine with a 0.4mm nozzle. But "print thin walls" already does this. So you don't want to go much thinner!

I think the wall is simply too thin by those holes. How thick is that space? Normally walls need to be 2X as thick as your line width. So if the line width is 0.4mm and the wall is 0.7mm then it won't print. You can print down to I think line width (0.4mm in this example) if you select "print thin walls". You can print thinner walls if you have a thinner nozzle. Expirment by changing all the line width parameters and check "print thin walls" in cura.

In top center make sure you are in PREPARE mode. Then in top left you should see your printer type. Click the arrow, then "manage printers" then "machine settings". In the gcode area you can move the gcodes around and insert your M80 wherever you want.

So I'm pretty sure cura has this feature but I don't understand it. But to enable the feature that you are asking about: Actually you probably only have to do the first thing: minimum wall flow to 50. Again - I totally do not understand this feature so I could be wrong but 2 people seem to agree this fixes thin wall issues.

It's called "hop". Search for "hop" in the settings and you will see "z hop when retracted". You need to uncheck that for UM printers. That is a useful feature for delta printers. I'm told. It only hops if it's a retraction move. There are other settings that decide which moves are retraction or non-retraction moves. If you look at the part in preview mode and check the "show moves" box you will see one type is light blue and the other dark blue.

Note that many amps (9 amps) go through this wire repair. So use a thick wire and make sure it has good electrical contact or it will get hot.

It's probably K1. That's the only relay. Here's how I fixed it. That was in 2014 and it still works great:

Note that if you lower the olsson block too much it hits the metal fan shroud and you have a whole new set of problems (block can't get up to temp once fans come one).

The isolator nut (the round nut) is designed initially for 2 nozzle printing to let you get the two nozzles the same height within 0.01mm (that's 10X thinner than 0.1mm - not a typo). So, no, it shouldn't leak. The thing that stops the leak is the gap between teflon and block. Please do the "pull" test and see how many pounds of force your feeder can pull. Test it once while "cold" and test it again after stepper is well warmed up (it's not really the stepper that has the heat issue - it's the stepper driver). Explained above issue #1 above. If pull test fails it could be #10,#17, or something else. Then if that passes concentrate on: 3,4,5,14,15 It really could be #3 - that you already wrecked your teflon somewhat. Just 3 hours at 240C might be enough. I don't know. One test for #3 is to remove bowden and nozzle, clear block of filament and let cool. Then slide filament through. Your budget is 10 pounds force - how much of that is used up by that friction? It's okay to drill out the teflon in situ. do it slowly and carefully. This will give you a few more days of printing while waiting for replacement. #15 - did you have this problem with 2 different nozzles? Maybe the newer nozzle is bad? This is less likely but worth considering.

Yeah something is wrong with your printer. It's printing at about half the volume you should be able to achieve. If you go into the menu on the machine you can see how many hours is on this printer. How old is it? How many hours of printing? Most likely the teflon needs replacing again already - probably due to being used at higher temperatures. There could be overheating issues or current-to-the-extruder-stepper issues but I doubt it. Also your bowden probably should be replaced. Bowden's get worn after a while. I sell regular and also "super slip" teflon bowdens. It really helps a lot to have the teflon bowden but personally I only have it on one of 7 printers. It also is more opaque so you can't see as much what is going on. Here is a complete list for what can cause a UM2 to underextrude. CAUSES FOR UNDEREXTRUSION UM2 AND HOW TO TEST FOR THEM AND REMEDY THEM One can quickly check the feeder (it takes seconds) so I would always do that first. The feeder on UM2+ and UM2 can push with 10 pounds (5kg) force easily so first thing is to lift that lever (if um2+, if um2 regular do move material) and insert filament so it is only part way into the bowden (e.g. half way). Then move the filament with "move material" command in menu so the feeder is energized and then pull down on the filament under the feeder. You should be able to pull with 5 to 10 pounds force without it slipping. Then have it move the material up while you pull down. 5 pounds force (2kg) is enough to make decent prints at moderate speeds listed below but you need 10 pounds (5kg) to print fast (e.g. 0.2mm layers and 60mm/sec) 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 (in cura 15.X. In cura 2.X it doesn't matter as much but still makes a difference). 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) UM2 only: 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) UM2 only: Bowden pushing too hard - for the same reason you don't want the bowden pushing too hard on the isolator. 6c) Um2 only: 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. I found soaking with acetone does not help with caramelized pla. Even overnight. Maybe it works on ABS though. Simpler cold pull: https://www.youtube.com/watch?v=u07m3HTNyEg 😎 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. On the black UM2 feeder 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. On the white UM2 plus and UM3 feeders you usually want the tension set in the center. 10) 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. 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 UM3 or 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 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. 14) 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 i nsert filament that has the pattern from the feeder. 15) 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. 16) 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. 17) 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 18) 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. 19) 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 nozzle 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. 20) non-standard or bent fan shroud. Sometimes people print some fan shroud off of thingiverse or youmagine out of PLA or ABS. Some of these are great but most of them are crap. One needs to do good air flow modeling. Also if it's PLA it will slump and direct air differently. Air directed at the block or nozzle can cause severe underextrusion and also sometimes HEATER ERROR. Put the original shroud back on or just turn off the fan to prove that the fan is the problem. 21) Firmware settings - for example UM2+ firmware on UM2 or vice versa will cause 2X over extrusion or 2X underextrusion. Downgrading or changing firmware can mess up steps/mm and other settings - so if you updated firmware and then problems started then do a "reset to factory settigns" which corrects all the steps/mm values. 22) 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 and 8mm for S5). 23) 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. 24) 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 25) Other feeder issues. You can test the feeder by putting the filament only part way down the bowden and with the feeder electrically turned on (or moving) pull very hard on the filament until it slips. You should be able to pull with about 5kg or 10 pounds of force before it slips. 4kg is acceptable. 2kg is a problem. If the stepper motor isn't engaged you can try going into the move menu. After a minute or so power is removed again from the feeder stepper.

Nice graph!! Thanks you for this. I have done similar graphs on an older version of this forum and the text is still here on this forum but the graphs got lost. Some points: 1) Please limit time that your block is > 220C. The teflon degrades faster as temperatures rise. 260C is just not good for that teflon. It lasts somewhere around 500-1000 hours at 210C and much less at 260C. The teflon is touching the heater block so 1mm or so of that teflon is at that temperature. And that's the part of the teflon that gets soft (part looks fine if you remove it) and collapses (squeezes) onto the filament under the pressure from the spring and the bowden at the top of the white teflon (you can see just by looking, without needing to take anything apart). 2) I've never seen wet PLA! I've seen wet PVA, wet Nylon, but never wet PLA. They steam and sizzle and pop and the filament comes out snowy -- full of air pockets. Like a sponge. If I leave Nylon out for just a few days it gets ruined and needs to be dried again. Try putting PLA on a heated bed or in a cup of water and notice that it starts getting soft (like clay) around 52C. If you dry PLA on the heated bed under a blanket or in an oven do not let the temperature exceed 50C!!! At that low temperature it will take (I'm guessing) 10 hours to dry out just the outer 20 meters or so of filament. Alternatively buy some 50 gram packs of color-changing dessicant and put the PLA in with those packs and recharge them when the change color until the spool goes a week without the packs changing color. I've left out PLA for a few years and never seen it get wet. 3) I tested ABS and nylon for max flow but never PETG! I had no idea it was less viscous. Good to know. 4) That sudden increase in flow at 260C is scary. I think there is some chemical change that may be a bad thing at that temperature. I really don't know. But at least realize that for ABS, if you get it too hot it caramelizes and clogs the nozzle. Unfortunately that "too hot" temperature is very close to normal printing temperature for ABS. ABS just sucks in many ways as a filament - stay away from it.

Okay now I hear that "factory reset" does not fix the problem. Instead it's recommended that you set autolevel to "never" and then do one more manual level and you should be good. I only level a few times per year. The leveling doesn't really change. So once it's dialed in you are good for thousands of prints.

They did change some thresholds. It sounds like if you set autolevel to "never" and do a manual leveling then you should be good to go. I only do manual leveling and I only have to level once or twice per year.

Instead of posting the gcode file, could you post the 3mf file? In cura do "file" "save" and it will save everything - your printer settings, your profile settings, your model, where you positioned the model, everything.

Okay - I heard from someone else that this bug is known and Factory Reset fixes the problem.

Okay - I heard from someone else that this bug is known and Factory Reset fixes the problem.