gr5

There are videos to show how to do this - google "cura support blocker".

Ah! Got it. You have many options. Your print probably doesn't need any support at all so you can probably just turn it off. However, to answer your question - you can use "support blocker". First click on your part so it is selected (don't know why this is necessary). On the left side of cura, there are a bunch of icons. The bottom one, "support blocker", (maybe 3rd from bottom) - click that, then click at that base of your part. It will create a cube there. Then while that is selected, use the other tools on the left side to move and scale your cube. You can uncheck the "lock" checkbox in scale mode if you want to scale the vertical differently from the x/y dimensions. Then do a slice and see how well that works. You might want to set "support horizontal expansion" to a small value or even to zero.

Please post some screen shots of the issue you are talking about. I don't want to guess what all your settings are. In addition to the screen shots it might be helpful to do a "file" "save" and save the 3mf file which will contain your STL file inside, and all your settings, and your profile and your machine settings. All stored in one 3mf file. But first please post screen shots. Maybe arrows to what you are talking about.

To get started - put your UM3 in developer mode and ssh into the printer. If you don't know what ssh is then you are probably taking on a project too complicated. On the printer are lots of python files. Nothing is compiled - everything is readable. Most of the code is in python an the "py" files. well commented. Nothing is obscured. There is a second computer on the UM3, an arduino style computer. That is running Marlin. That is published somewhere but I forget where at the moment. Most of what you might want to experiment with however is on the linux machine.

It's not cura doing this. The curves are in the STL file. Your CAD software is doing that when it converts to STL. What software are you using? Most of them have options where you can set resolution for the STL. Don't go overboard. Probably 1mm is good enough. If you get too many triangles in the STL you can have millions of triangles for a simple shape (like a cylinder). Also it can be a problem printing - the printer can only buffer 16 moves so it might slow down to a crawl if you have too many triangles in the STL.

It's all about squish. Your glass isn't quite flat. It's probly roughly mountain shaped - thicker in center and lower on the 4 corners. And it's most perfectly leveled at the 3 screws. When you imagine this in 3d and imagine the the back center and front right two corners are perfectly levelled such that the mountain glass is tilted. It follows that the rear 2 corners will both be low. You can check your glass and if it's more than 0.3mm out of flat then maybe get a new one. You might be able to get one for free from your distributor. But it's probably within 0.3mm and you just need to squish more in the back to get it to stick everywhere. So just turn that screw CCW a half turn or so. Some people put thin coins under portions of the glass (the glass easily bends the .3mm or so needed to make it back to level).

In cura, in machine settings (prepare mode, click on your machine at top left, "manage printers") there is the option to have 0,0 be in the bottom left or in the center of your printer. You want 0,0 to be in the bottom left corner so that it will print in the center.

Absolutely, but more likely low jerk/accel could be the cause. If you have overshoot or ringing (I see neither in your print) then you need to tighten the belts. What I see doesn't look like those - what I see in the photo looks like overextrusion briefly. This can be caused due to speed changes or other strange movements like coasting and others. Overextrusion is usually worse with low jerk/accel because the printer slows down for longer and that high pressure in the nozzle causes it to squirt out and make a bump. With high jerk/accel the printer either doesn't slow down at all or it slows down so briefly it's not enough to cause pressure buildup in the nozzle. I'd look very carefully at the gcodes happening right when these bumps happen. Maybe use the free "repetier" software that lets you see gcode and 3d view of the gcodes at the same time. You can highlight a gcode or a group of them on the right window and see where in your model they happen in the left window.

If it's not your STL there are simple to use drag and drop repair services out there like this one: https://3d-print.jomatik.de/en/index.php

That could be moisture in your filament but it really looks more like underextrusion. Here are some ideas: 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. If the white marker isn't in the center, make sure the adjustment screw actually moves the marker. If not then someone put the feeder back together wrong. 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 21) Filament tangle - the end of the filament can get tucked under a loop on the spool and this tangle can propagate from then forever to the end of the spool until you fix it. It will cause many many jam ups and slow then halt extrusion. Repeatedly. The fix is to remove the filament from the printer, unroll a few meters and respool and put back on the printer. Never let go of the end of the filament spool until it's in the bowden. =======

I would print faster - maybe 25mm/sec at least but I suspect this has nothing to do with your issue. The telling piece of information is the 1mm thickness. Look at this part in preview mode and look at the blue movement lines (make sure travel color is enabled) and look at the difference between bottom 1/3 and top 1/3 of your part. I don't know exactly how to improve your part - maybe make it a bit thicker (the upper part is probably thicker when viewed as horizontal slices wheras the thickness as travelled by a normal (perpendicular to surface) is probably always 1mm as you say. Therefore it appears the thicker areas are doing better. You might also try the MB/burtoogle version of Cura which does better with "thin" walls. Less craziness, less moves: https://www.dropbox.com/sh/s43vqzmi4d2bqe2/AAADdYdSu9iwcKa0Knqgurm4a?dl=0&lst=

I'm 99% sure the problem is in the STL. There are so many crap STLs out there. Especially ones created with sketchup. A good cad software will not even have a way to create non-manifold designs yet with sketchup it takes extra work to remember to seal in your parts and you have to tell sketchup which is the inside and which side of each face is facing the air. Anyway, I think in older versions of Cura you had to install the mesh plugin to get that message. Now I guess the manifold check is built in? It's probably that. Try viewing the model in xray view to potentially see the problem in red.

Yes! Great idea! Cura has this feature. It's more complicated than you show as areas that need support aren't always perfectly flat. But it does save a lot of PVA and for the part you show above it saves a lot of time as well. In Cura the feature is called... well I don't know what it is called. This feature was added recently so make sure you have the latest version of Cura.

The nice thing about printrun/pronterface is that you can issue gcodes manually and adjust these values and issue G commands to move the axes. I think M500 can save the acceleration values permanently (so you don't lose them on power cycle). You should also keep good notes and maybe edit Configuration.h so that if you ever do a "reset to factory settings" you don't lose your hard work.

It's the printer, not the gcode. There is some fast/violent move that is identical on each layer and you are losing one full step on the stepper. It's the same on every layer because it's exactly one full step and because the slicer is doing the same fast move on each layer. It's probably the stepper. If it was pulleys then it wouldn't be so consistent. Either adjust the current or more likely, lower the acceleration and jerk. Try cutting them both in half. You'll have to play with these values. Hopefully you have a firmware that lets you change this easily for example with a gcode and you can do many moves with higher and higher accelerations to see where it slips and then maybe cut that value in half. Same with jerk. I'd use pronterface or similar so I can command the fastest possible moves and just do simple, long moves back and forth adjusting max speed, accel, jerk settings. Anyway also it's possible a pulley slipped. If you have pulleys and belts then tighten the set screws more. You need to tighten the hell out of those set screws - your allen wrench should be twisting a little. If you have a tiny L shaped wrench then it should hurt your fingers. Usually the pulley on the stepper. Pay attention to if it was slipping in X or Y as that's the only axis you have to tighten. It's also possible the belts are so loose they slipped a tooth.

burtoogle is also known as smartavionics and his version of cura is on github. Just not the executables: https://github.com/smartavionics?tab=repositories It's always dodgy to download some exe and run it but I can vouch for burtoogle. I've met him in person and he seems like a good person who wants to make the world a better place.

If it's a non-retracting combing move (as I suspect) there is an option in Cura to retract on combing moves longer than a certain distance (for example 100mm). I'm pretty sure that feature is in normal cura but if not then it is in the MB version as I use this feature: https://www.dropbox.com/sh/s43vqzmi4d2bqe2/AAADdYdSu9iwcKa0Knqgurm4a?dl=0&lst= It's called: Max comb distance with no retract

I don't know. This is pretty much impossible to do on curves but you don't have curves. In PREVIEW mode, make sure travel move checkbox is checked and the blue lines are non-printing moves. There are two different colors of blue - one for retraction moves and one for non-retracting. You can check to make sure it is doing a retracting move before starting to print the "bad" area by seeing which shade of blue it is.

Usually high jerk and high acceleration reduce blemishes. Everytime the extruder slows down or speeds up you get over or under extrusion. However 15mm/sec is crazy slow. Well below jerk setting such that the extruder should not be speeding up or slowing down at all. So I'm not sure what is causing your blemishes. Did you try the "outer before inner" setting?

I hope you don't mind me answering in english. I had the same issue and I opened up the controller housing (removed all the screws that hold the wood together around the controller. There is a potentiometer in there. Use a tiny screw driver to turn that many turns. Try both CW and CCW. I think it's a 10 turn potentiometer (can rotate 10 times). If that doesn't work, remove the ribbon cable connectors and check for bent pins and reconnect carefully. Don't lose track of the orientation of the ribbon cables. Do this on both ends of the cables.

200 meters is oldish. It should probably last for 2000 but since you just showed that the feeder is fine I would swap out the core next. I would expect a core to last as long as the printer (they are built very well) but Ultimaker considers them consumables - part of the cost of printing. Maybe they are right about that.

Also set all the printing speeds to be the same speed (all 6 or so). Everytime there is a speed change you can get over or under extrusion. And that looks like underextrusion I think. On the outermost layer. Maybe watch it printing very carefully in layer view and see what happens just before it prints that edge (outer most shell only).

Aren't those the begining of the line? So there was this horrible error in the AA 0.8 PLA fast profile that had the option "retract on layer change" checked. For no apparent reason. That was causing horrible underextrusion on my 0.8mm print until I found that (strange) setting checked. I'm wondering if that error (which has since been corrected) somehow made its way into other profiles (ABS).

Try checking "outer before inner" and set ALL printing speeds to 35mm/sec (no speed changes allowed). Travel speed should be fast - 150 to 300mm/sec

I took another look at the photos. Make sure all the printing speeds are the same speed! There's like 6 printing speeds (leave travel speed fast - 150 to 300mm/sec). Also try cleaning the top 2 inches of the Z screw (where it is used to print these shield holders). Make sure to get all three grooves as the UM3 and S5 have triple helix.