illuminarti

Oops. If I sent you a salvaged encoder from a scrap board, would that help? :-)

Remember it's also quite possible that the surfaces which were designed as straight, and look straight to the eye, really aren't straight when exported as an STL. STL's are only an approximation of the original surface, and most CAD packages allow you to specify how closely (or not) the triangle mesh of the STL follows the surface of the modeled shape. This is especially true with curves. Within the resolution of the STL, it's quite possible that a flat surface that ends in a curve actually has it's end point slightly offset from the 'true' endpoint, in order to match up with the adjacent curve. The exact behavior of the inside and outside surfaces of that wall might be different, so that the wall isn't exactly the right thickness all the way along its length. Depending on how much tolerance the slicer has for these things, that might tip it over the edge from deciding that it can get, say, four lines of shell into a wall, to getting only 3.99 lines, and deciding to handle that as 3 lines plus some infill. I think that Cura sometimes errs on the side of over-precision, when slicing these sorts of thing, but it's important to also remember that the STL is not perfect either.

Also, yes, Cura will never so a single pass to print a thin section of STL like a custom support. This is basically because the part has a continuous face around it, and Cura wants to print that continuous loop of shell. It may reduce your effective shell thickness in that area to a single nozzle-width, but to make a single loop around the thin shape, you are going to end up with the two sides touching one another. It will allow the two passes to overlap slightly but not completely. If the overlap would be too great, it just filters that section out totally. So I think you can print (with two, slightly overlapping passes) a wall that is 1.5 times thicker than the nozzle width, but not any thinner. (But it's been a while since I looked at that so I don't exactly remember the details, or know whether the implementation has changed recently). Cura could possibly be smarter and just use a single pass, but it isn't. When you think about it, it starts getting pretty complicated unless you treat everything as a collection of full loops, with more or less infill inside them. Especially considering that STL files describe the geometry in an almost totally context-free way. You know that you have a surface, but not what it means, or how the parts relate to one another. It's just lots of triangles that the slicer has to intersect with planes, and then make sense off the jumble of lines that results.

With curves or lines that are not parallel to the the axes, there is going to be some amount of rounding errors which are going to cause slightly less than optimal things to happen. Firstly, note that if you have a part that is designed with a wall that is 1.6mm thick in the STL, then you should really set the shell to 0.8mm, since Cura is going to try and print a shell on both sides of your wall. Or alternatively, just make the part solid in the STL, and print it with zero infill, and a 1.6mm shell to get four concentric passes by definition. I'm not sure that some of what you're seeing isn't due to Cura trying to figure out how to fit twice as much shell as will fit into the available space. Overlap isn't used for the shell passes, but it might affect where Cura thinks it has space to put some infill in what is left after the shell parts are done, I'm not sure. (Also note that the overlap is calculated parallel to the direction of travel of the infill line, and relative to the centerpoint of the nozzle location when starting/ending the infill line. This means that the infill actually overlaps more than the expected amount, because if the infill line ends with the center of the nozzle, say, 15% past the edge of the concentric shell pass, there's a further semi-circle of infill beyond that center point, overlapping the shell even more). Depending on the angle between the edge and the infill, the effect of this extra overlap can be more or less pronounced.) Additionally, Cura internally requires that the shell thickness is an exact multiple of the nozzle (i.e., extrusion) width. If it isn't, it will pretend that the nozzle is a different size from what it really is, to get that exact multiple. In the first cases above, changing the shell width is changing the nozzle width, and so allowing the slicer to exactly fit four passes into a space that it thinks is fractionally too tight. Here's a write up I did a long time ago about how cura handles this. The infill spacing bug that I identified then is no longer present, and quickprint is now a bit saner, but the basic way in which it adjusts the extrusion width is still valid: http://www.extrudable.me/2013/04/08/walls-and-nozzles-and-cura-oh-my-or-quickprint-is-broken/ (Shell thickness used to be called 'wall thickness', which is what that article calls it).

Yes, the white part is the coupler. Isolator nut the thing it sits in. It looks like you had some filament stuck either in, or under, the coupler. Just make sure that afterwards, the coupler has settled back down straight inside the isolator, so that there's about a 1mm gap between the top of the isolator and the wide part of the coupler.

What program are you using for slicing, Merardo? If it's Cura, you'll need to make sure that you tell it to generate 'Ultigcode', not normal Marlin/Reprap gcode. If you are using another slicer, you'll need to adjust the starting gcode to advance the filament at least 20mm before printing, to counteract the automatic 20mm retract at the end of the print, and then an additional 8mm or so to actually flush plastic through. The first movement you can do at say 5mm/s (300mm/min) since the filament shouldn't actually be extruding, just moving into the empty head. The second part you should do at 1mm/sec (60mm/min) to simulate a normal fast-ish print speed. Also, make sure you have the firmware installed from Cura 14.07 (check the version in Maintenance -> Advanced -> Version, on the printer), as earlier firmwares had some issues with grinding away the filament by doing those purges too fast.

If you heat the head, and remove the Bowden tube at the printhead end, then you should be able to just pull the filament out of the nozzle. The only place it could possibly have gotten stuck is if the white PTFE coupler has lifted up inside the isolator nut (the thing with holes in), and plastic has gotten under the PTFE part, but above the nozzle. Is your teflon sitting higher, or at an angle or anything? In that case, you might want to unscrew the nozzle, and take the ptfe part out to clean things, remove the filament and reseat it. If not, then the filament should just pull out of the hot end.

You can't really prevent it, and you don't want to. It does this pre-print purge and prime to clean out any filament that has sat heated for a while, and so might have degraded a bit, and also to ensure that the head is fully pressurized with plastic so that the print starts correctly. Simply get a pair of needle-nosed tweezers, and pull the pile of filament away from the head before the print starts.

Is the nozzle clogged, or did the filament simply get ground at the extruder motor end? Actual clogged nozzles are pretty rare: the most likely point of failure is the the extruder motor. If you remove the Bowden tube and heat the nozzle, are you able to push filament through by hand?

If combing is enabled, then it won't retract on moves within the 'interior' of the object. Also, the 'minimal extrusion distance' is applied - Cura won't fire a second retraction until that much filament has been printed, to avoid grinding over the same spot. This distance is measured in mm of filament input into the printer.

But 'feeling' resistance of a sprung bed against a small nozzle is very hard to do consistently anyway - especially if the springs are not properly compressed. What you want to avoid is leveling it too high, because then the first layer won't stick; I think that most of the time people overthink it. The only thing the bed height adjustment affects is the first layer; so just level it by eye - you'll take a fraction of the time, and end up slightly too close which is good for first layer adhesion anyway.

The issue with printing small areas is that they don't have enough time to cool down between layers. And if you use a 'minimum layer time' setting to create enough time, then you end up slowing the print down so much that the head jsut sits over the print anyway, leaking heat into the print and melting the already printed part. If possible, you should print multiple parts at once, so that the head can be printing a layer of one part while the other one cools a bit. That could be a second copy of your object, or just a sacrificial piece like a simple tower or something to keep the head busy for a few extra seconds per layer. Alternatively, in the expert settings, Cura has a 'cool head lift' option which will move the head away for a few seconds on each pass. The head will probably ooze a bit, and end up leaving a fern-like mess growing off the side of your print, but it's usually quite easy to clean that up, and preferable to a melted print.

The retractions speed and distance settings are available on the 'Advanced' tab, if you have configured it to generate traditional 'Reprap/Marlin' gcode. If Cura is configured for the Ultimaker², then you do not get to edit those settings, as retraction speed and distance are configured on the printer for the Ultimaker², as part of the material settings.

I voted!

The quiet fast ticks from the extruder are normal - it just seems to happen at certain extrusion speeds; don't worry about it. The only thing that is an issue is when the extruder is making a loud click and jumping back 1/8 to 1/4 of a turn. As Blizz says, that's due to too much pressure in the extrusion system, so that the motor is stalling. And it is normal for it to happen during the filament load process, or when printing the first layer, if the head is a bit too close to the bed. In Ultcolin's case, if you are getting gouges in the filament, and it stops feeding, you should NOT push it into the Bowden tube - that is simply asking for problems later. Rather, you should take the filament out and cut off the damaged parts, and then reload the filament. Increasing the pressure on the extruder idler will usually help. For printers made after mid-March 2014, you want the white indicator mark somewhere around the second line on the scale on the extruder housing. (Printers prior to that have a different spring, and the indicator should be all the way to the top).

Randy - Here are some things to check: 1) Are the gantry cross-rods that go through the head fully seated in the sliding blocks? If you look down on the printer from above, are all four sliding blocks aligned parallel to the side of the printer, and not tipped in or outwards? 2) If you remove the glass from the bed, are all of the screwheads for the adjustment screws and glass clips at or below the level of the heated bed surface? 3) If you sit the printer on a hard flat surface, does it sit flat, or does it rock because one corner is higher than the others?

You need to customize the start gcode to manually extrude the appropriate amount of filament before the print. Note that you don't get any additional settings to customize by using the repRap gcode flavor - the settings are simply fixed in Cura, rather than being set on the printer.

The thickness of glue should be irrelevant; if you are doing it right the glue should be almost imperceptibly thin; apply it lightly and then spread it with a wet paper towel until it all dissolves. Then allow it do dry during the bed heatup, so that it leaves an almost invisible film on the glass. I get to level a lot of print beds every day, and here's how I do it: The first thing to do is to make sure that all of your springs are reasonably tight. If they aren't, it's impossible to find the right height with a single sheet of paper, because the tension on the springs is minimal until they're compressed a bit. So, look through the bed from front to back, and adjust the back thumbscrew until the terminal block in the back left corner is about 1mm from touching the lower plate. Tighten the front screws about the same amount, to keep the bed roughly level as a starting point. Then heat the nozzle and make sure it is clean at the tip. Now run the leveling wizard again. When adjusting the rear height, just use the dial on the front of the printer. When adjusting the front corners, use the thumbscrews. I recommend not using the 1mm-then-a-paper-thickness approach. Instead, on both passes level the bed to the point where the nozzle just touches the glass. This is easy to see if you look along the surface of the glass; you can see the nozzle touch its own reflection. This approach will leave you 0.1mm closer than the firmware expects, but in conjunction with a 0.25 or 0.3mm first layer height, it helps to ensure that the first layer gets nicely squashed onto the glass for good adhesion. When setting each point, move the bed up until it just touches the nozzle tip, then back it off and allow it to settle untouched, and then gently close the gap again. If you find that you cannot compress the front springs enough to get the bed down to where it needs to be, then simply raise the back of the bed a few turns of the thumbscrew, and restart the leveling wizard. You want to end up with all the springs in a middle position, with a gap of about 10-13mm between the two plates of the bed assembly. The springs should be neither totally compressed, nor so loose that they aren't applying any meaningful upward force on the bed. By doing two passes at the same height you should get fewer surprises; the second pass around should only require very minor adjustments. And aiming for the point where the nozzle touches the glass is a much easier target than trying to interpret the feel of nozzle on paper tension.

Replacing the board, or at least the terminal block would be the best way to go - but if you're careful, you should be able to just solder the wires from the thermocouple directly to the metal pins that are still sticking out of the board.

The blobbing when using cool head lift is exactly the same as stringing, it's just stringing to itself. The upside is that it should be quite easy to cut off, as the ooze is only even attached to the print at the very bottom. Like George says - given how Cura reverses the order of island printing on each layer, you get two layers back-to-back on the first and last pieces on each layer, so you need at least 3 to get the best possible results. Also, there's probably no need to print with a brim on a small part like this; it's a quick print with a relatively high contact area, considering the height of the piece. Given that the layer alignment is a lot worse when printing multiple pieces at once, it seems that you have some backlash issues. I'd check that your short belts are properly tight; power the machine off and grab the print head and move it quickly back and forth in one axis then the other. Watch the corresponding short belt move, and make sure that there are no signs of twisting and jumping. If you squint at the belt, you shouldn't really be able to see it moving, because it should be moving back and forth in exactly the same path (aside from any visible motion of printing on the belt). If the belt is jumping or twisting at all, then loosen the four screws holding the motor, and press down on the motor while retightening them.

What is the issue with Cura that is preventing you from upgrading the firmware? What temperature are you printing at, and with what material? TEMP3 is just the bed temp sensor, yes. It could be that you are getting bad temp readings; certainly printing with the head cooler will tend to make it harder to get things to stick. You can measure the temperature directly with a digital thermometer and a surface temperature probe, but I'm guessing you probably don't have one of those :-)

Start/End gcode in Cura is only available when it is configured for normal gcode output. When set up for the Ultimaker², it isn't there, because all the start and ending stuff is done in the firmware.

Just level the bed with the head a touch too close to the glass, and print at a fairly high temperature (and get a bit lucky).

I'm sorry that you didn't get faster responses to your questions; although it might not seem like it from your experience, Ultimaker very much cares about its customers, and wants them to have the best possible ownership experience. You should have received some responses now, and I'm hopeful that you'll be able to get your issues identified and resolved as soon as possible.

Almost certainly the problem you are having is not with the nozzle being blocked; since you could push filament out by hand, the nozzle is fine. Check the filament at the extruder motor end at the back of the printer, and make sure it isn't damaged. If the filament is rubbed away or has gouges and deformations, make sure you cut those off. What material are you printing with?