gr5

You have severe underextrusion. Here is a list of possible causes. The plus feeder is great and the quickest thing to test. Print out wedgebot (it's on youmagine) as everyone needs a wedgebot anyway. Use that to get the filament inserted half way down the bowden then remove wedgebot and do "move material" to energize the servo and then try to pull the filament down out of the printer. The plus feeder can easily hold 10 pounds (5kg) if it's working properly. It's good to eliminate this issue right at the start. Think about each issue below carefully. I'm sure you can eliminate many of them just by thinking about them but think carefully. CAUSES FOR UNDEREXTRUSION UM2 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 (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). 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.

The S5 should be able to go to 200mm/sec absolutely no problem. At some point innfill doesn't connect well. You can play with the speed *during* a print. You can go up to (I think) 500%. So slice with *all* printing speeds at say 100mm/sec and set the nonextruding move to 200mm/sec and then you can set the percentage to say 75 to get 75mm/sec and then set it to 150% to get 150mm/sec and so on. You'll see that the infill doesn't connect so well internally on larger parts and long straight runs can have vibrational issues but in general you are probably okay at 200mm/sec. However usually I like to achieve faster printing speeds by printing thicker layers and with fat nozzles like a 0.8 or 1.0 nozzle (3dsolex has 1.0 and 1.2 nozzles (among others) for their hardcore for the S5 and disclaimer: I sell 3dsolex parts in USA). If you care more about dimensional accuracy and don't care about ringing which makes 3d printed text look like crap but is not measurable with a micrometer, then remove uncheck "jerk control" and "acceleration control". It will print both faster and more accurately.

When you slice with cura it puts some profile information in the bottom of the file. Cura 15.* and older encrypts this into a digital packet. If you see a completely 100% nonsense characters at the end of the file then you need Cura 15 which you can download from the cura download page. If it's sliced with cura 2.* and newer it has a human readable packet at the end of the file. It's not super easy to read and has weird characters but if you read it slowly you will realize it is actually quite readable. You can even write it all down as it only shows *exceptions* to the default profile and tells you which profile it used (e.g. draft). So... open the gcode file in a text editor or if you don't have one, use word. Look at the comments at the top and then skip to the very bottom of the file and look at that as well. Maybe it was sliced with some other slicer like s3d (simplify 3d).

I would rather have 2 UM3s than an S5. Or one Um3 and 2 um2gos. Because "quantity has a quality all on it's own". Using the S5 is a nice experience, true, but it costs a lot more. Also bigger is slower. Only slightly slower. But slower.

prime tower is probably the best solution as smithy says. Why ABS? That's not really the best material for any application I know of. If you want strength, ABS is no stronger than PLA. If you want high temperature consider PETG.

So I think you are getting bad underextrusion. Since I see lots of horizontal lines I think the Z movement is inconsistent - sometimes Z moves too far or not far enough. So imagine this: if the z axis moves too far you get an entire layer that is underextruded as the gap is bigger then the extruded amount intended for the smaller gap requested. This can be caused by dirty screws or faulty bearings or faulty z nuts and screws or other Z related issues.

Wow. Sounds like a bug. I recommend you post some screen shots and post it in github as that's the best place to post bugs. https://github.com/ultimaker/curaengine/issues You have to create a (free) github account to post.

PVA is harder to print than PLA and there is a learning curve. In this particular case most likely your PVA got too wet. You can dry it out by putting it on a print bed set to 80C overnight with a towel over it. That should help quite a bit. loosen the spool a bit also to let moisture out. Never leave the PVA on the printer for longer than necessary. For day long prints I keep the pva in a ziplock bag with just a small hole to let the pva out and 2 large packs (250g?) of freshlay baked dessicant.

Ask bondtech. They are very helpful.

Did you read my comment about thin walls? Did you try "print thin walls"? Try setting the line width to less than half the width of those walls. So if the walls are 0.1mm try setting the line width to 0.03mm (even if you don't have a nozzle that small - just to see if the problem is that the walls are too thin). If that doesn't fix it then I'd assume it's something to do with the red areas in xray mode.

I was about to mention that the walls are probably too thin to print. By default they need to be line_width*2. But you can check "print thin walls" to print thinner walls. However now I see your exray view had red. LOTS OF RED. That is not good. It may be unrelated though. I looks like the top of your object is double walled. Also the bottom. I don't understand how it could be red in xray mode and invisible in solid view mode. Does it have a top or not?

I would model the support in cad.

It varies too much. If I raise the temperature by 10C it can seal up a 0.1mm gap that was there before. There are test prints on thingiverse that are helpful. Really you just have to experiment. Also when I am near the end of a spool of filament I get more underextrusion which is only obvious on gaps like this which grow a bit. Also the bottom layer has special requirements. You want to overextrude the bottom layer and by default it does. This makes the parts stick much better to the print bed. But it also can fill small gaps like this. So you might want to set "initial layer horizontal expansion" to a negative value. But if you set it to an overly large negative value and you have thin walls then the walls won't print at all on the bottom layer. So you might have to increase the gap size in cad for the bottom layer. Or just cut the bottom layer with a knife after the print is complete.

I really don't think it's related to the "2 color" thing. Did you see all those red dots in xray view? That's a hint probably. Can you union all the overlapping volumes in meshmixer? For example if you create 2 spheres and overlap them there should be a way to remove the internal walls of the 2 spheres. Some kind of union feature or "make manifold" or something. I don't know meshmixer very well. What happens if you try to slice just one of the two colors. In other words just load the cape/wings and see if that has the gap. Then just load the rest of mothman and see if it has a gap. If it works fine separately but not together then maybe you are right.

Customer support people around the world tell me that architects drive them crazy more than any other profession that uses UM printers (maybe dentists are worse I suppose). Now I can see why! lol! Note that printing just the faces on all these bricks will be a ton of retractions and you could grind the filament up possibly if you don't print enough between retractions. So I recommend you do these settings to limit retractions. 10 retractions on the same spot of filament is safe. 20 is dangerous but should work. 40 is almost certain failure. Set "maximum retraction count" to 10 to be safe (or if you are getting failures where it grinds up the filament and stops extruding) and "minimum extrusion distance window" to 4.5mm (the default retraction distance or close enough if yours is a little different). You might not hit the limit of 10 but better to be safe. The downside is when it occasionally doesn't retract you *might* get a little string. That reminds me: Also I hear architects love white filament which strings the most. 🙂

I'm not sure the absolute minimum width. Whatever you use for line width (I use 0.4mm line width for 0.4mm nozzle but I think default is 0.35) - double that and that's the nominal minimum width. So 0.8mm. But in reality you can go thinner if you check the box "print thin walls". I think there is no lower limit but I recommend you go at least nozzle width (0.4mm). If you print with a 0.25mm nozzle then you could go down to 0.25mm but you would see the color below coming through a bit. Also a 0.25mm nozzle prints 4X slower (2x thinner layers and thinner lines) so a 2 day print is suddenly an 8 day print. Yikes.

Yes! I agree. It is only slightly more flexible. If you take 10cm of regular pla and 10cm of tough pla, one in each hand, you can barely tell the difference. I really notice it though when I am loading filament (I never use the auto loading thing - I always slide filament in by hand on all my printers: UM2, UM3, S5).

The feeders can pull/push with more than 10 pounds or 5kg of force. A little friction of the spools touching is too small to matter. I'm going to split your problem into 3 categories of problems (although there are 20 possibilities): 1) Feeder 2) print core 3) too many retractions #3 is simplest to fix and diagnose. Some layers may have hundreds of retractions. By default Cura lets you do 30 or 40 retractions on the same spot of filament and that can grind it up. 10 retractions on the exact same spot is safe. 20 is pushing it. 40 almost guaranteed to fail. So look at the failing layer in cura and count up retractions to get a feel for this. You can change retraction settings if necessary. It's probably more likely #2 than #1 but #1 is easy to test. You need this thing anyway so print one of these to help with loading, unloading filament and testing things (to physically feel yourself what it feels like when working properly): https://www.youmagine.com/designs/wedgebot-for-ultimaker2 Now feed the filament half way down the bowden and do "move material" on the menu to energize the extruder and then pull down on the filament hard. You should be able to pull at least 10 pounds without the filament slipping. Tension on feeder should be in the center position of the indicator. #2 - try changing cores. Obviously if that fixes the issue then the problem was with the core. 3dsolex cores are nice because you can change the nozzle. A bad core can usually be cleaned with hot and cold pulls (see this feature on the UM3 menu system). You may have a "bad" core. It's kind of a mystery to me what makes a core bad but it's common. I think it's related to the teflon insdert somehow. Even 3dsolex cores can be problem cores (but most are fine). (I sell 3dsolex cores so I'm biased but I do believe they are better). Once you get a tangle in filament it will not go away unless you remove the tangle. The tangle just travels along forever if you don't fix it. If you never lose the end of the filament (hard to do) it will never tangle. It is possible to remove a tangle by passing the entire spool "through the knot". Hard to explain but easy once you figure it out.

It's a bad model. I looked at the model and sliced it and see the same gap. If you look at the model in xray view it has tons of red spots. That's the problem. The model is not "manifold". It is not a single solid model. Did you make this model? Lots of cad software can convert models with overlapping volumes into a single solid volume (or 2 volumes in your case - one for the cape). Or you could try fixing the model in netfab. netfabb free repair service is here (you have to create a free acocunt first): https://service.netfabb.com/login.php Although I don't know if netfab works on formats other than STL. You could split your 3mf into 2 STL files and fix each one separately.

Nice!

I think it's random. It slices a layer of STL triangles in to random unconnected line segments (because STL files don't say which triangles are connected). Then it tries to connect line segments together into loops. Each loop of line segments is stored in a data structure - basically a linked list. It prints in the order that they are in the structure probably. But it doesn't always print starting at the begining of the data structure. But I think it always prints in the same order. So when it creates these loops it could start off clockwise or counter clockwise. So maybe it's controlled by the STL file and what order the triangles are found in there. The first triangle found in the STL for a given layer starts the loop and then where it finds the first adjoining triangle - that will set the direction. Most likely. You could experiment with a simple STL file - maybe a cylinder. Find the very first triangle in the STL file and it's xyz position. Find the adjoining (horizontally) triangle and swap them to see if it changes the CW versus CCW travel. [edit: note: I was wrong. Correction in next post]

Tough PLA is indeed slightly more flexible. It's most obvious when handling the raw filament. It is subtle though. It seems very similar to PLA mostly. The flexibility is what makes it tough. It is actually weaker than regular PLA. Also I think it probably stretches a little more before breaking (for example clay isn't flexible exactly - it just deforms (permanentlyish) before breaking). This graph shows more stiff to the right on the X axis and stronger vertical on the Y axis. Both axes are logarithmic. You can click and drag to zoom in. http://gr5.org/mat/

You have to model the 2 colors as solids. It looks like 3 colors in the photo. Anyway, for example you could make some bricks one color and some another. Or you could divide the brick in half along a diagonal or any division you want. But when you get the colored volumes figured out you then create 2 STL files one for each file. Each STL file must have solids (not faces, not surfaces). In cura you assign each STL file to a different color then select them, right click, and merge them into one part. You don't want overlaps as it will print twice in the same volume if overlapping (a little overlapping is sometimes okay or possibly desired if you are doing some clever trick). Does that make it more clear?

This is by far the best way to upgrade to dual extrusion (link below). The original plan for the UM2 to do dual extrusion doesn't work very well at all and I don't want to explain why. Your biggest problem with the mark2 is that UM stopped putting a driver chip for the second extruder on most circuit boards so you might want to look on the board to see if that is missing before going very far with the mark 2 option.

Pay particular attention to faces that are gray versus white in sketchup. Read that part first maybe: https://i.materialise.com/blog/3d-printing-with-sketchup/