gr5

No! The thin wall problem is very well known and understood. Cura is much better than other slicers that I know of for thin walls. Instead you should either print thicker walls or get a smaller diameter nozzle. Or write a whole new slicer. e.g. Cura insists on 2 passes but can get very close to your shell thickness but kisslicer which only insists on one pass does a much worse job on thin walls. Cura is actually pretty amazing how well it handles thin walls. If instead you leave the nozzle at .4mm and set the "shell" thickness to .3mm you can get some decent results with hardware that "shouldn't be able" to print that thin.

It's most likely one of the 2 X limit switches. Are the cables getting tangled up in the belts maybe? When a limit switch triggers for a given axis the other axis keeps going. You can unplug the X switch on the right side as you really don't need it. Marlin has "software endstops" which work quite well. If that's the problem switch then you are "done". If it's the left one you have to figure out whats going on. I would turn off power and hook up a multimeter to the far end of the limit switch cable (under the UM) and then push the head around and poke at the wires and such.

For UM Original: If your nozzle is cold I still recommend using paper as it gets thicker when it heats up (thermal expansion). If your nozzle is hot I recommend turning the 4 screws 1/8 turn to compensate for the paper thickness. @anon4321 - I added "UM Original" to your title to clarify. Also I changed the all caps as it seemed a little too emotional. For people new to the printer, using paper gets you "close enough" with the default .3mm first layer in Cura. As you get more experienced you slowly learn the more intricate details like the fact that you have to worry if your nozzle is hot or not, if there is a tiny bit of plastic on the bottom of the nozzle, if your heated bed is hot or not (if you have one) and you have to know to compensate for all of those things plus the thickness of the paper.

Daid already fixed this. I'm not sure if it's in the latest RC or not. It will be out in the next release. Occasionally when he fixes one bug he creates another. That has happened twice in the last few months that a I know about. Fortunately he fixes it quickly. (quickly compared to say releases of microsoft windows patches/fixes).

It seems to me there are 3 solutions to this problem right now: 1) Modify firmware to go up 5mm instead of 3mm. This is advanced and if you haven't compiled the firmware will probalby take you a few hours. 2) Always raise the bed a few mm before you start a print. And before you level it. 3) Bend the Z limit switch a tiny bit so that the bed hits it 1mm lower than normal. I don't have this problem as the distance between all the way down and limit switch opens is 2.7mm. I measured this by twisting the Z screw with power off and I get 17 "stepper clicks" which is 2.72mm = 17/(6.25 full steps/mm). So bend the z limit switch down until you have 17 or less clicks between all the way down and limit switch open. This gives you the full printing volume also.

There are 3 solutions right now: 1) Modify firmware to go up 5mm instead of 3mm. This is advanced and if you haven't compiled the firmware will probalby take you a few hours. 2) Always raise the bed a few mm before you start a print. And before you level it. 3) Bend the Z limit switch a tiny bit so that the bed hits it 1mm lower than normal. I don't have this problem as the distance between all the way down and limit switch opens is 2.7mm. I measured this by twisting the Z screw with power off and I get 17 "stepper clicks" which is 2.72mm = 17/(6.25 full steps/mm). So bend the z limit switch down until you have 17 or less clicks between all the way down and limit switch open. edit: Oops - bend it *down* not up - you want the Z switch to get hit in a lower bed position.

I think what dimensioneer is saying is that you can do "fix horrible A" and it will fill in the entire cube, then turn off infill (set to 0%) and set shell thickness to 0.4mm. This should get you what you want if the object is *very* simple (e.g. no holes).

Instead of changing the firmware you could just raise the Z switch a little bit - that way you will get more vertical build volume. Just bend that little lever so the bed hits the Z switch 1mm sooner.

My bed never droops when power is off. I have to push pretty hard to make it go down. Hard enough that I always push down at the rear. UM put an amazing amount of grease on my lead screw. The assembly instructions for the UM1 said to use about the amount of grease in 1 pea. My UM2 has enough grease for 20 peas I think. However when the UM2 finishes, the bed always goes to "down" position (actually probably right where the Z switch clicks). I measured the distance from all the way down (mechanically stopped) to raising where the Z switch opens. It's about 3.0mm +/- .2mm on my machine. So even if I *did* push the bed all the way down the firmware will bring the bed up 3mm before homing so no problem. I also measured this distance by rotating the Z screw and it was 16 servo steps one time and 17 steps the other 2 times. Not sure how many steps/mm the Z is. Firmware says 200 microsteps/mm but that would mean 1/32 stepping rate - if true then it's only 2.7mm and I will never see the problems you saw. I have had parts that need quite a bit of force to get them off the bed. I was removing them with the bed in the down position. I'm surprised I never moved the bed any further down. It never occurred to me to raise the bed 2mm before starting another print.

offset = f_04b036ptDescriptors[index][2]; That's not valid for accessing program memory. You have to use the pgm_read_word() function like this: offset = (uint16_t)pgm_read_word(&f_04b036ptDescriptors[index][2]); Or alternatively you should be able to do (but above syntax better and I may have the ptr math all wrong here): offset = (uint16_t)pgm_read_word(f_04b036ptDescriptors+index*3+2);

I can easily print 10 or 20 things without releveling. Even when the first layer is .1mm.

I'm glad none of the cotton got lost inside the nozzle! That would be bad as it would cause it's own clog.

The radius of the nozzle is .2mm (diameter=.4mm) so Cura moves the tool path towards the inside of the object (not inside of the curve) by .2mm. So when doing the outer wall of a hollow cylinder the path is .2mm inward and when printing the inner wall it moves .2mm outward. You can buy smaller nozzles (e.g. .25mm) for the UM Original but for the UM2 you would need a good mechanic to do it as soldering (filling existing hole) and precision delicate drilling is involved.

Did you use this for your source? https://github.com/Ultimaker/Ultimaker2Marlin If so then in Configuration.h I found: #ifndef MOTHERBOARD #define MOTHERBOARD 72 #endif So I suspect 72 is correct. The UM1 uses the arduino mega2560. I don't know which arduino chip the UM2 uses.

I think you will need some support also to keep it from falling over. Maybe model the support in cad - maybe every 2 inches it could use 3 supports that you cut and sand off later. Also try any infill > 25% - for example try 50% - I think you will find that is more balanced/radially-symmetrical.

This issue seems to have been solved today! And it's not what anyone thought it was... http://umforum.ultimaker.com/index.php?/topic/5935-z-axis-homing-inconsistent-on-um2-workaround-and-patch/&do=findComment&comment=54270

Oh - and you should do the pull request now - it doesn't hurt to do a request. And if you aren't quick enough, Daid will do it without you and you won't get your name immortalized as a "Marlin Author".

I'm surprised there is a homing retract distance - I always assumed it reversed until the switch went back the other way. This is a good find. There are 2 or 3 people out there with this problem. I think including NicoLinux. I'll message him right away.

There should be photos here: ultimaker2 assembly manual - click "raw" to download the pdf: https://github.com/Ultimaker/Ultimaker2/blob/master/um2%20assembly%20manual%20V1.1%20_english.pdf

Did you already remove the bowden tube? That's recommended for the atomic method. When doing the atomic method if you get the right temperature the filament should come out in the exact shape of the nozzle including a .4mm bit of filament where the nozzle hole was. If you don't get that cone-shaped tip then lower the temperature another 3C before pulling up. You can definitely take apart the head. You don't need instructions other than beware that some threads might have solid PLA in them so heat the head to 180C while you take it apart. Also at some point you will want to slide out the heater and temp sensor but you have to remove that long skinny screw first - you'll see it after you take the white teflon piece out. Seriously - just start - you only have to remove 4 thumb screws, then 2 screws holding the fan in, then you can remove the white teflon piece and rotate the round nut using the holes in it (but you must be at 180C when rotating that nut) and finally the skinny screw removed to get the heater and temp sensor out. Not hard. Just start doing it.

So you only soaked the nozzle?

I like it quite a lot also. I am still much faster in sketchup but I try to do everything in DSM now. Illuminarti bought the full version (spaceClaim). I'm quite good in DSM but need to start assigning shortcut keys to get as fast (about 10X faster) as I am in google sketchup. But I love the feel of DSM - I like the workflow better than sketchup. I like that you don't have to worry about accidentally creating holes in your part or inner walls.

Which step is slow? The part where it does the little progress bar up under the icon near the top of the screen? Or the part where it loads layers and does the "10% complete" progress text? Or is the model not even visible for a long time? Or something else?

@miss3 - I don't think pinterest will host your pictures for decades so please instead post your pictures here: http://umforum.ultimaker.com/index.php?/topic/4525-how-to-upload-an-image-to-the-forum/

One could easily write a plugin that does what Eldrick wants.