gr5

It's not a problem of the polymer. The problem is viscocity, pressure, and the strength of the feeder. The feeder can only push so hard on the filament until it grinds up into dust. The UM3 feeders can push with about 10 to 15 pounds of force. Getting the filament with a consistency of toothpaste to go through a 0.4mm nozzle at 5 mm^3/sec at 230C requries a lot of pressure - around 1000psi. The UM3 feeder can't always achieve this (by the way is your feeder set to the middle position? you want it in the middle position). You say 235C made no difference but that's hard to believe. I'd like to see a print where the nozzles were at 235C or where you printed at half speed or half the layer height. It might not be perfect but it should have a significant improvement. In the UM3 tune menu you should be able to set the speed to 30%. And you should be able to increase the temp by up to 25C. I'd like to see what happens when you do that first. You could print for 5 minutes at a time with different settings all in the same print to get some ideas of how bad your situation is so I can get an idea if this is a hardware issue or just that you are printing too cold/fast. I'll give you some speed numbers next - from old experiments...

Three thoughts: 1) retraction. Check the print in layer view and try to find these spots and see what happens there and in particular if there are any light blue lines in these spots which are retraction moves - you might need to play with the retraction distance. Retracting too much or not enough can cause spots just like these. 2) speed. Try printing at half speed - it's amazing how much better the quality can be. 3) slicer. Try cura 15.04. I'm not sure but it seems like some of these blemishes don't happen in cura 15.04. I don't understand why as it's the same slicer engine but some setting or something may have changed. Many people (many!) have had better luck with cura 15.04. However I have had excellent results with cura 3.X so I don't know what's going on. What kind of printer is this?

3dsolex sells a ruby nozzle for UM3. Look for "hardcore" which is their version of the UM core and "everlast" which means ruby. These nozzles can print 20 spools of CF filament with no wear. Woodfill should be fine with just an ordinary brass nozzle but each manufacturer is different and the size of the wood particles is different so look at what they recommend as the minimum nozzle size. 3dsolex also sells a 0.6mm core. The nice thing about the 3dsolex cores is you can just buy one core and change nozzles. disclaimer - I am the distributor for 3dsolex products in USA so I am a bit biased.

nice. Is this your design?

Ooh. I wouldn't do that. If it's PLA and is at all old (has been on a shelf for a year before you got it) then this will ruin it. More info here: Basically if you even just straighten it and let it sit like that for a day or so it will be incredibly brittle and break into pieces or if it doesn't it will break going into the bowden. I think you just have to leave it alone on the spool and have a good powerful feeder. Maybe print 30% slower the last 1/3 of the spool. Maybe. Or get a powerful feeder like that on the UM3, the S5, the UM2+ or get a bondtech feeder. Or a medusa feeder.

Contact 3dsolex - link to this thread - see if they'll send you a free ICE coated 0.8mm nozzle. The ice coating is basically teflon - nothing should stick to it. If you go over 240C it ruins the ice coating and maybe that is what happened to your nozzle? Or maybe it was never ICE coated. The ice coated nozzles look a lot like steel. They are darker and less shiny than uncoated nozzles which are quite shiny (like chrome). I found that I have to print about 10C to 15C cooler with my 3dsolex 0.8 nozzle than with my UM nozzle because of the RACE technology which has the filament going down two different paths through the nozzle and heating the filament more thoroughly.

Oh that looks good. I think you did a good job in sketchup there. Congratulations. I still recommend you bail on sketchup if you have less than 100 hours experience with it. If you don't please please read that guide above. Also ALWAYS look at the part in layer view and run the layer slider up and down - pay particular attention to the bottom layer but also pay attention to possible overhang situations.

You should call your reseller because they might be able to help you for free. Although you may have violated your warranty at this point (for this particular issue. I really don't know how that works so I'd contact them right away. Anyway you need the nylon to get to about 150C so that it is soft enough to pull it all off. If the core still works heat that to 200C and let it sit for maybe 30 minutes, then start with the heatgun as necessary. It takes dozens of minutes for that heat to penetrate enough to start removing chunks so go easy and slow. You went much too hot. But I doubt you caused any permanent damage yet.

Do you man the "plus" kit? If so you have to download new firmware afterwards because the "plus" feeder has a different number of steps/mm for the E axis than the non-plus. If you downloaded new firmware it's good to do a "factory reset" which sets all the steps/mm and many other settings back to default for that printer. Anyway, this link shows a good explanation of where not to plug the fan into by erin from fbrc8:

Oh and here is a good guide to pick cad software: https://www.gliffy.com/go/publish/5271448

Are you sure? Cura likes an input of STL files. I have never heard of cad software that can't output STL file. Check the documentation. I'm pretty sure I've used freecad and I'm pretty sure it can create STL files which cura loves.

sketchup is a bit dangerous with 3d prints - it's better for virtual models - not physical models - so if you haven't spend a hundred hours learning sketchup I strongly advise you to stop right now and use something else. Here's a guide to pick CAD: https://www.gliffy.com/go/publish/5271448 However if you really want to stick with sketchup then you need to completely read this guide and understand it. Particularly about the reversing walls part: https://i.materialise.com/blog/3d-printing-with-sketchup/ Now to answer your question - I think I need a screenshot of your stl in cura in normal view, xray view, and layer view to understand what you are talking about. By default I think cura does a 20% to 30% infill which should fill in your part with a criss-cross kind of pattern in the "solid" areas. If you set infill to 100% you should get solid parts. But that's a huge waste of money and time for no inmprovment in strength. The gradient thing you speak of is called "gradual infill" and it's a great feature - I use it all the time. But I think there is something lost in the translation - I strongly suspect your sketchup model has some serious issues that are confusing cura thus causing these "hollow" things you speak of.

No this is nice and slow. 2.3mm^3/sec should be absolutely no problem. Something is wrong. Eliminate the slicer first since slicers are so damn complicated.

Any text editor will work. For example on Windows you can use notepad. Search for the letter "Z". It will be one of the first 3 Z's in the gcode file most likely. Something like: G1 Z0.27 Which means move Z axis to position 0.27mm. Or more likely: G1 X101.11 Y34.37 X0.27

Well I don't know S3D very well so I'd definitely also try using cura at least just for one print to see if it suddenly works just fine. This will eliminate a LOT of variables either if it works fine or also underextrudes.

So layer height .15, line width .44 (why wider than nozzle? I recommend narrower than nozzle for example 0.35 is best on um3), nozzle width .4, speed 35mm/sec. .15 * .44 * 35 = 2.3 mm^3/sec You should be able to do that no problem. Well there's lots of other possibilities. Here's a list below. You can ignore #1 and #18. #14 and #16 are the first 2 things I would check for as it takes all of a few seconds to know if you've every printed glass fill, carbon fill or glowfill. And the middle fan comes on when a core gets above 50C - trivial to check. Next I would try a cold pull. Also known as atomic pull. There are instructions on the UM3 in the menu system - it guides you through the process. 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. 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. 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).

FYI @smartavionics

Even if you slice at 0.1mm layer height, the bottom layer is typically 0.27mm or .3mm (depending on the version of cura and which profile you have). Assuming .3mm: So Cura sets the Z height to exactly 0.3mm and extrudes exactly enough for .3mm worth of material. However I agree it works better if you overextrude the bottom layer. For some printers like a UMO this is very difficult to do. The solution is a parameter called "initial layer flow". You can set that to somewhere around 150%to get a nicely squished bottom layer so your part sticks well. Or you could edit the gcode file by hand and change the .3 to .15.

All I can say is your bottom layer was severely underextruded but the layers above are fine. That is always a leveling issue. Does cr10 have auto leveling? If so a bit of filament on the tip of the nozzle can mess that up. I am not a fan of auto leveling.

I agree - it's too high poly. Most likely. For example if you print a 1cm cube with rounded corners and there are 20 points on the corners - well that's a problem because marlin (the firmware inside the UM3) can only look at up to 16 points at a time and has to slow down enough so it can stop within the next 16 points. If the next 16 points are within 1mm then you get these pauses where the points are too close together. Plus the computer is working so hard weird bugs pop up like the display jumping. If it's not your STL you can decimate it - try cutting the polygons by 3X: http://www.shapeways.com/tutorials/polygon_reduction_with_meshlab

I think the latest firmware for UM3 is getting more strict. I don't know how to turn it off. You should look at the list of complaints though. here are some of them: Core1 type (e.g. hardcore versus AA 0.4 versus BB 0.8 etc) Core2 type (even if not used possibly) filament1 filament2 printer type (extended versus standard) If you want the printer not to complain then you need those above 5 things to match between the printer and the slicer. It's okay to lie a bit. For example if you have ABS in the printer but you sliced for PLA you could tell the printer that PLA is loaded. I don't know why you would do this but it would get rid of one of the warnings. Let us know which of these 5 things (or another?) doesn't agree that you can't get rid of and we can help you get rid of the annoying message.

If you click on one of those 3 parts you can then click the icon on the left side of the screen that has the "move" hover tip. Then you can move that part. It looks like you have the wipe tower enabled. You might want to disable that if you want to get a 4th part on there.

Can't you just set infill to 0% in slicer? That should get rid of the honeycomb. Maybe also set skin or shells or wall (or whatever the parameter is called) such that it only does one pass on the outer shell. Also disable any "support" structures.

Turn off combing for bottom layer. Combing is a complicated feature and does several things - it should probably be split up into multiple sub-features. anyway when combing is on you don't get retractions within an "island". To be more exact set "combing mode" to "not in skin".

There is a search box above all the settings - type any of those 3 words in that box. I recommend the word "support" as that will show many of the other support features you may be interested in.