gr5

This is underextrusion. Most often caused by printing too much volume of plastic in too short of a time. What is your: layer height nozzle diameter line width (all of them) print speed (all printing speeds) printing temperature (all of them) And is your filament PLA? For example you can print about 5 cubic mm/sec of PLA through a 0.4mm nozzle at 230C but not at 210C. To get cubic mm/sec multiple 3 things: line width, print speed, layer height. Same formula as volume of a box.

Did that involve changing any feeder components or changing firmware?

This is extreme over extrusion. I don't know what is causing it. I've seen this MANY times. In fact I've had about 10 prints exactly like this in the last 3 weeks. It was caused by Cura issues in cura 3.2.1 and cura 3.3.1. I was able to fix it by doing one of 3 things (any ONE of these fixed it): slow to 20mm/sec (yuk!), turn off acceleration control (probably already off on UM2), turn off gradual infill. Doing any one of those made the print go from this to perfect. I don't know why. I'm told there is a bug in gradual infill but I don't see why it would cause this issue. I suspect you have a different issue causing over extrusion. The most likely causes are Z axis or E axis is out of calibration. If you print a tiny 1cm cube is it 1cm tall? Or 1/2 cm tall? It's possible for the Z to be off by 2X simply by plugging a fan cable into the wrong spot on the PCB. Or by loading new firmware. Also calibrate your extruder. Could it be off by 2X? Maybe move the extruder 100mm and see if the filament moves 100mm in the tube (start with filament for example half way in the bowden tube). Did you change firmware recently? Did you change feeders recently?

examples of how bottom layer should look. These pictures are from the internet mostly and I am just guessing that the bottom layer height for all of these is 0.3mm (cura defaults to 0.3 or 0.27 depending). The numbers below indicate my best guess as to how far the nozzle was from the bed (again assuming .3mm is nominal). The blue one is about perfect if you want it to stick really well. the yellow one is a bit too squished but at least the part WILL NEVER COME LOOSE! lol. The black one is similar to what you are printing but even worse than what you did. The red one is okay for small prints but for large prints they may come loose. I aim for red or blue depending on my goals. If I want it to stick better I squish a little more. If I don't want the bottom layer to have a tiny brim I usually just set initial horizontal expansion to -0.2 or so but sometimes I instead go with what you see in red below.

I've seen this hundreds of times. On my own prints as well. Your nozzle is too far from the glass. So the first layer is barely sticking at all. So as it prints those circles on the bottom layer sometimes they become triangles or other shapes. What kind of printer is this? If this is an Ultimaker then just turn the 3 bottom screws a half turn CCW to move the glass up a bit.

Okay so I guess it's not quite a duplicate but seems like a waste as some of the same solutions are being posted here as over on the other thread. Anyway I think maybe this feature *does* exist in cura: support wall count I think that's the feature. Make sure you have the core2 selected of course! In the top right corner.

You don't need a fancy drier to dry your filament as you can use your printer (if it's not busy of course - if it's busy then it's cheaper to buy a drier than to buy a second printer obviously). I put filament on the glass and cover with a towel. heat it up and leave it like that for many hours. I have had to dry ninjaflex and nylon but not pva yet so I'm not sure what temperature pva gets soft at (I think maybe around 80C) so you would have to test a small piece first at a few temps to find the highest safe temp (it dries MUCH faster at 80C than 60C I'm sure but if you melt it all into one blob it's ruined).

Did you play with this? Is this what you have been asking about all along? Is this the exact feature you have been asking for?

Sorry I didn't see this earlier. If I don't answer you feel free to post simply a "@gr5" once per day until I notice. I check the forums > 5 times per day but the forum is not designed in a way that I notice everything. 70mm/sec X 0.35 X 0.2mm is (if you multiply these 3 numbers) 4.9 cubic mm per second. 4.9 is pushing it. My notes say you can do that at 230C but no way at 205C. So you need to either: reduce layer height to 0.1 reduce speed to 30mm/sec (max for .2 layers, .4 nozzle and 205C print temp increase temp to 230C (and suffer bad overhang quality) You don't have to do all 3! Just one of those. Or you can do a 4th thing - use a 0.6 or 0.8 nozzle. I suggest you either relax and live with much slower printing times or use a larger nozzle. Regarding retractions - that's nothing. You should see the amount of retractions when printing the eiffel tower or a voronai vase.

yes. Then follow kman's instructions.

What kind of printer do you have?

Make sure "retract at layer change" is turned off. That's the first thing that comes to mind when I look at that photo. Also look at all the speeds (there's something like 6 printing speeds) in 2.7 versus 3.3. Also look at line widths. It could be that the outer most shell is a different line width than whatever prints immediately before. I prefer to make all the line widths the same for the most part.

Seriously - if you need to print that thing with much accuracy you are not likely to be happy with a FFF printer like an Ultimaker. It can do it but this part is on the small end of what an FFF printer can do. Instead, look at the form2 printer first. Or b9creator. Have people print that thing for you first. Especially shapeways. Don't buy a printer until you have seen what that printer can do and held your part in your hands printed with the actual model of printer you are thinking of buying.

Okay well, after reading what you posted over in the other topic and re-reading this you have lots of ways to strengthen the structure. Line width and Horizontal expansion really will make the most difference but there are many other parameters to make it thicker/stronger. To make something vertical more resistant to being bent and then breaking in half you only need to make it slightly wider to make it much stronger. "support wall count" is probably what you have been asking about. You can set this to 2 for example and you will have double walls around your support structure made from support. For all of these make sure you select the second core in the top right corner of cura. Look at all the other support features - you can change support density, support pattern and a few dozen other parameters. The reason you probably did not get very good answers right away is that I've just never seen this particular problem - my pva support doesn't tend to break off like that. Never seen that. Not sure what's going on.

This is a duplicate topic. I'm locking it which means no replies allowed. Please post over in the other topic instead:

Here's a great dfm article by iRoberti: http://support.3dverkstan.se/article/38-designing-for-3d-printing

I liked the way daid did it with several different topics - each linked to the next. The first posting in each topic had a link to the next and previous topics (eventually - you have to edit in the "next" link after you post the next article). Because people don't want to have to read comments like this one and the last 2 which won't teach them anything about design. geert maybe should post his own topic and steve can link the first post in this topic to geert's post and vice-versa.

windows/mac/linux? The com port is probably tied up for some reason. You could reboot or kill all processes that might be using the com port (some version of cura might be semi-crashed but locking up the com port). When you plug the usb into the computer (if it's windows) you should hear a particular sound (ba dunk). where the second not is a higher pitch. When unplug it is almost the same sound but the pitch goes down. When you hear the upward pitch you can open device manager (on windows) and you should see a USB service pop up and then dissapear and a COM service pop up. Check that all that is working to simplify if the issue is maybe not related to cura at all. If you have windows I strongly recommend using cura to slice but then use pronterface to print over USB. It has amazing features.

I'm running the latest cura (3.3.1) and it doesn't let me choose materials for um2go so I think that's normal for UM2. I recommend Cura 15.X over cura 2.3. I think it's easier to use and less buggy. Cura 3.X is great but cura 2.3 not so great.

Well to answer your original question: "line width". Select the second extruder near the top and change "line width". 0.5mm is pretty safe with a 0.4mm core.

Or ability to have 2 towers - one for each material. And you can print one or both depending which material(s) you feel need the tower. The downside is if you have two separate towers you are printing twice as much because currently it does this: change nozzles, then print ONLY ONE layer of tower, then print TWO LAYERS OF ONTO THE PART, then repeat. With only one tower it has to print on the tower just after the nozzle change and again before it changes to the other nozzle. Either that or the tower layers would have to be twice as thick as the print layers. That would have a danger of heavy undextrusion on the tower and overextrusion the first few seconds of printing the part.

The bug in 3.3.1 doesn't cause bad quality parts (unless they are large hollow cylinders) and typically only increases print time by 10% so it's not all that serious unless you are on a hunt to get the fastest print time without losing quality. The 0.3mm layer height is the key point here. Also the makerbot slicer isn't as good at predicting actual print times as cura is. Going from 0.1mm layer height (your setting) to 0.3mm layer height (his setting) should give you a 3x speed increase right there alone. The other major issue is probably how makerbot slicer predicts print times. We set the print speed in these slicers and the slicer tells the printer the speed. However these printers have accleration limits. So for a large part with lots of long straight printing paths (or only slightly curved) it will run at full speed. But for your print with many short line segments to print the printer often never even gets up to full speed. Cura is better at predicting this (for a Um2 - which has acceleration at 5meters/sec/sec). On your particular printer the acceleration might be even lower and you may find that your printer is significantly slower than cura predicts. For UM2 printers it is amazingly accurate on the print times.

Oh. This. This would be a good feature.

Oh and avoid cura 3.3.1 - it has a combing related bug that makes printing slower. Stick to 3.2.1 or 3.4 when it comes out.

I'd go to 0.2mm layers. That should save you a ton of time. And I'd probably print it slower and with 0% infill. Default settings for me in cura said 7 hours. That was with .2 layers, 10% infill, 3 shells (you have 2 which is plenty) and print speed at 30mm/sec (all print speeds). To get this down to 2 hours you could maybe use a 0.8mm nozzle and do one pass on the walls with 0.3mm layer height. And maybe increase the print speed to 40mm/sec. 0.1mm layer is not going to increase the quality much if at all. You'll probably get a better quality with 0.2mm layers and a slower printing speed.