gr5

That "wind scar" looks like infill showing through. Did you have infill turned on? Hopefully you haven't re-sliced yet and you can go to the gcode view in cura and see if where the infill touches the edge matches the "scar". You can probably fix this by setting your wall thickness thicker. So if you are at .4 go to .8. If at .8 go to 1.2. The latest Cura has a bug (a feature?, an issue?) where the infill can stick out through the wall. I have another post showing what's different in the new infill: http://umforum.ultimaker.com/index.php?/topic/2501-is-this-slicing-settings-or-hardware-problem/?p=17683 That post was a week ago when Daid wasn't posting much so he might not have read it.

I can't imagine how rotating the object can help, but something you didn't mention: tighten or loosen the belts.

If you do a through scientific test, and can summarize your results in "pictures with words on it", please post a summary of your results here: http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/ Note that the second photo was posted by someone who tried to remove non-ringing vertical lines purely by adjusting temperature. Or post the pictures in the current topic and maybe I'll add the words onto the photos for you (assuming you have photos).

Every machine is different so you'll have to home, then us pronterface or cura to move the head to position x=205 and then move 1mm at a time until it triggers the limit switch. You can go to the value *before* it hit the limit switch. Repeat this test for Y and Z axis. If you hit the limit switch during printing it will mess up your print. If you try to go over the limit switch by .1mm you probably won't notice anything, but a whole mm over will mess up your print.

That's the infill pattern sticking through the wall (I'm pretty sure but could be wrong). You can confirm by checking before the top layer is printed. You could set overlap to around -15% or I would turn it off (set infill to 0) and infill using "shell" only as Illuminarti kind of suggested. Or see if you can get cura 13.03.X (or older) which doesn't overlap the infill quite so badly. I would try Illuminarti's suggestion of lying to cura and telling it your head size is .5 with shell thickness 1.0 (you can set shell thickness to 100mm if you want and it will stop making shell when it meets in the middle). See what it looks like in gcode.

Or you can do what I did and put the value in Cura under "file" "preferences" and the first line of gcode out of cura will always override the Marlin settings.

You can get damn close. You can get to about .1mm if you adjust your CAD parts. Plastic shrinks. You have the same problem with other manufacturing techniques - if you have critical dimensions you sometimes have to do a test print first to figure out how far off your critical dimensions are. Typically my only critical dimension might be along one axis or might just be the size of holes. With experience and consistency of PLA and Cura settings you can predict how much to make the holes larger ahead of time and don't need to print a test print. My rule of thumb is always make holes .5mm larger and if anything else is critical, print about 2mm height, pause the printer, measure it on the bed and if it's too big or small, abort the print and adjust the CAD model. Z dimensions tend to be the most accurate and for large parts X and Y tends to be extremely accurate.

This is a very common problem. Either the bed is too high or too low. How to level: Levelling here is defined as setting the Z height and also levelling. It's one procedure that does both at once. Optionally heat up the nozzle to 180C if first layer is .1mm or less because a cold nozzle shrinks and you will be setting the bed to the wrong height. Make sure tip of nozzle doesn't have any plastic on it or you may level to the wrong height. Home the z axis only. If you must home all 3 then you need to disable the steppers once it's done so you can move the print head by hand. Move the head as close as possible to each of the 4 screws in turn. Once at a screw tighten the screw and then slip a piece of paper between the nozzle and the print bed. Make sure the paper slides very freeley. Then loosen the screw until the paper gets slightly stuck. You want the paper to easily be able to slide in and out under the nozzle with one hand pushing the paper. If the paper gets stuck it's probably too tight under there. Repeat this procedure for the other 3 screws. Then go back to the first screw and repeat on all 4 screws again. Then repeat on all 4 screws again. Then again. It may take you 20 minutes to do this the first time but the second time you do this it should take much less time because you are both better at it, faster at it, and because there isn't much to adjust the second time. If you levelled with a cold nozzle you are done. If you levelled with a hot nozzle you should then loosen the 4 screws 1/8 of a turn to compensate for the thickness of the paper. Once done levelling rotate the z screw by hand to keep the nozzle off your bed. This makes it less likely to damage your bed surface and gives the nozzle room to leak. On a new ultimaker repeat this procedure before every print (at least every hour) because the print bed can move/droop like a new guitar string. After many months the droop slows down.

What country do you live in? You probably know it by another name. Tell me the country and I'll tell you what they call it in your country. It's sold at any store that sells bandages. http://www.instructables.com/files/deriv/F4O/57VU/FAQCIOXU/F4O57VUFAQCIOXU.LARGE.jpg

My spring is at 11.5mm. But maybe we have different springs.

Maybe you need a new nozzle. It might have a chip or pit.

Sounds like something is wrong with your nozzle - maybe some gunk on the tip or maybe it got damaged. I'd look at it with a loupe. Or reading glasses. Or a microscope.

I'm still using the one that came with my UM although I repaired it a bit with kapton tape when I accidentally melted part of it. It is still in the same shape as the original.

I was thinking waist. jeez.

Don't presume that someone else will do a better job of "calibrating" it. Recently someone posted results from their prebuilt and were not happy and had to do a little calibrating (although personally I think they were unnecessarily upset). One of the key things is bed leveling and this will change when shipped and must be done quite often regardless because of the nature of the cantilevered design which tends to move over the time span of days. Better to buy a used ultimaker that was truly and properly tuned by a loving owner than one built by a UM employee. UM still has low volume compared to most consumer products and so they haven't fine tuned their assembly process like say foxconn has with their iphones.

More details about extrusion speed bug: http://umforum.ultimaker.com/index.php?/topic/1734-marlin-bug-the-myth-of-retraction-speed/ I use speed of 40mm/sec and have this bug so it's actually 20mm/sec I guess. Note that this speed doesn't affect normal printing which is much slower, but mostly affects retraction.

So I agree it is stringing. Possibly extreme stringing. Pretty easy to get rid of - read my post above. I'm wondering about that retraction speed of 60 though. I don't think it's possible for the retraction motor to move that fast. Maybe try 20? Marlin changed the code that controls the extruder stepper and there was a bug and I have a version from last December (with the bug) and I assume you have a version with the bug fixed (actually maybe not - not sure if Daid has updated Marlin in Cura since December) so I can't really speak intelligently about the speed other than 60 seems too high. The bug made higher speeds slower so 40 might give you 20 and 60 might give you 10 or something bizarre like that - I really don't know the details. But a slow retraction speed would give the filament time to blob. I really recommend you do a test just like that stringing test print in my post above.

You could have just looked at the gcode in cura. Be default cura shows the model as a 3d object you can pan, zoom, rotate around (right click drag, both click drag, shift right click drag). In the top right corner is an icon to view in other modes which can be very helpful. One of them is "layers" which shows the gcode visually in 3D. You can select the layer you care about with the slider and zoom in and around the problem or questionable area with the 3D mouse movement.

I always set the cura temp to 0 and set the temp with the ulticontroller (or cura). I usually make the first layer hotter at 240C and then when almost done with first layer I lower the temp. No need for this to be done automatically. Having the temp set to 0 is nice cause I can start the print as the temp is passing 235 and by the time the home is finished and the brim or skirt are started the temp is close enough to 240 to start. You can get steeper angles (more than 80 degrees possibly) with thinner layers. You can't make the nozzle hole any bigger (it's .4mm) but the thinner the layers, the less z changes for a sideways movement of up to .4. So if layer height is .1 you should be able to get a slope of 1/4 or arctan(1/4) = 76 degrees from vertical. layer height of .05 in theory gives you atan(1/8) which is 83 degrees from vertical. Also it's important to keep the part cool (more than 5 seconds per layer and fan on) if you want good overhang results.

Ah. Great. This makes sense. You can probably order the power supply now. You should probably get a 24V supply > 260 watts. In fact since the resistance could be as low as 2 ohms then it needs to be > 288 watts. In fact I would get at least 350 watts to be safe (don't want the PS to burn out on a hot day or if you leave it under a towel or something and it over heats).

yes. Oh well. That would be a good design change. Not sure. The rippling could be "ringing" caused by each line segment but it seems unlikely as the change in velocity is small at each vertex. More likely the rippling is caused by the infill pattern overlapping too much. The latest Cura calculates infill overlap differently and it's kind of a problem. Best fixed by making the "skin" .8mm so that the infill is less likely to bump out the skin.

It looks okay - sorry - I think it's the picture - I can't quite see what the problem is. Or is this considered good? Maybe you need to show at an angle also? Anyway, I'm sure we will hear more from you as there are still things you will have problems with and we will have solutions for you now that you are mostly past "bed levelling". Next is probably "damn it - my parts are warping and lifting off the bed". Or "my part gets knocked off the bed before printing is done". Or underextrusion issues. Or stringing issues. Or overhang issues.

I would probably leave it alone as I've never heard of the pulley being out of line causing nonlinearity issues but if you want to take apart anything in the ultimaker start here (you can get here by going to the main ultimaker website and clicking assembly instructions on the left side): http://wiki.ultimaker.com/Ultimaker_rev.4_assembly:_X-Y_axes

That's actually common. Or the rods that set the print head height can be warped. The warpage is usually no more than about .1mm but if your first layer is .1mm thick... Less expensive printers usually print a raft which hides the bed warpage. Cura defaults I beleive to a .3mm first layer and I usually go with that for most prints. I replaced my bed with a flatter bed but it's not really that big a deal.

Oh. Those bearings. I forgot what they looked like. Those seem a little more specialized. No idea, sorry.