gr5

Good question - some people have addressed this very question recently: http://umforum.ultimaker.com/index.php?/topic/5208-why-should-i/?hl=buying&do=findComment&comment=47209 http://umforum.ultimaker.com/index.php?/topic/5281-ultimaker-2-or-replicator-2x/?hl=buying&do=findComment&comment=46929 (well similar question anyway).

Can you confirm if it is only the X axis that is slipping? Or only the Y axis? Or both? In the bottom print it looks like only the X axis. There is a bug in an older version of Marlin from a year or more ago related to moves when all 3 axis move at the same time. It is rare to move all 3 axes at the same time. Illuminarti understands this bug better than me. I still think you have a slipping pulley. Did you remove the stepper motor for the slipping axis and mark the rod and pulley and then later check that? And tighten that pulley the most? There are 6 pulleys that can slip - 4 on the long belts but maybe you forgot the 2 on the short belts? The problem is definitely either slipping pulleys or slipping steps. To avoid slipping steps you can try to lower the jerk and acceleration. Speed is not important. You can lower both using the ulticontroller if you have one. But this is a bad solution because it means you are changing software to avoid a hardware issue (friction).

UM Original or UM2? On my UM2 one screw was rattling. I just removed it and have only 3 screws for that fan and it has been fine since.

Oh - and if possible - don't create any more tickets (I have never created one so I don't know the process). I think they are usually handled first-in-first-out. So if there is a way to refer to an existing ticket that might work better. You can also message Sander or Marrit directly (Marrit link provided below) and refer to your ticket and refer to this thread/topic by copying the URL above and pasting it in your correspondence: http://umforum.ultimaker.com/index.php?/user/1841-marrit/ - George

Videos (maybe using your phone) would probably help. So if you go to maintenance menu and say lower build plate it raises it? And if you say raise build plate it also raises it? How do you ever lower it? There is a DIR signal (direction) that goes from the arduino chip to the servo driver. If this signal has a bad solder then the signal floats and it pretty much will only go one direction forever. The other signal from the arduino chip to the servo driver is "step" which is a pulsed signal. The way the servo is built it either doesn't work at all (for example one broken wire and it won't move) or it works completely. So it can't be the wiring or the motor - it has to be the white board (PCB) underneath. If you are handy with a soldering iron I would reheat the two pins that are potentially bad (DIR signal). Otherwise I would go back to your ticket (hopefully you did one at support.ultimaker.com) and mention that the Z axis only goes one way and that gr5 says it's most likely the PCB. Then have them send you a new one and you can change it out yourself (very easy). There's only 2 screws covering that PCB. Ultimaker tests everything well before shipping but shipping (DHL/FEDEX) is very good at breaking these printers. That's why it is best if they ship you only the PCB so you don't get a printer with some other thing broken during shipping.

Just so you know - letters flat on a top surface are difficult. They will come out much better on a vertical surface so it's usually best to print something like that sideways. The nozzle diameter on UM, UM2 and I think most makerbots is 0.4mm which is kind of big for little letters like that. That sound sucks though - sounds like something is broken. The UM2 is pretty quiet. Only the Z axis is noisy. I can be 2 rooms away with doors open and I hear nothing until the print ends and the Z axis moves all the way down.

Went to a minimakerfaire in cape code massachusetts Saturday. Had fun. Here's a 54 second video:

Burning calories through exercise is counter productive in that it makes you hungrier and an hours exercise for me is only about 400 calories or a small desert. Plus after burning those calories I slow down and use less calories than usual for the next 4 hours. Don't get me wrong - exercise is fantastic when you are trying to lose weight but really the best way to lose weight is to take a scale with you wherever you go and weigh everything and count those calories exactly. The fun thing to do is to graph calories versus weight in excel and you can do moving averages on both and see the correlation and figure out exactly what qty of calories is your break even point and what qty of calories you need to lose at a particular rate (e.g. 1kg per week). Counting calories is the only sure way to lose weight. After doing this for a while you can usually guess the calories of something pretty accurately.

Hmm. That should work fine but if you have a print fail and you want to continue it the next day (after homing again), you want the homing repeatability to at least .1mm accuracy (if not more!). So hopefully that little blue thing is repeatable and doesn't squish much. Some people instead bend the metal part of the switch - they bend it a lot! Maybe give it a 90 degree turn 3mm from the end.

And then there's this solution also: http://umforum.ultimaker.com/index.php?/topic/1676-modification-of-upgraded-extruder-drive/?hl=%2Breplace+%2Bdelrin

The two color method of printing text works for very small objects also.

Here's the actual code: https://github.com/ErikZalm/Marlin/blob/Marlin_v1/Marlin/planner.cpp

You got it perfect so far. The X speed is changing from 60 to 38 as it slows down so if X acceleration is set to 3000 (common values are 1K, 3K, and 5k - 5K works fine on UM2 but prints have less ringing at 3K) then it will decelerate the X axis at 3000 mm^2/sec aproaching postition "5" on your graph. All movements must be linear (in 4 axes X,Y,Z,E). This means the E axis (which due to printing thin layers and other factors is usually not the limiting acceleration) will decelerate at the appropriate rate for an X decelration at 3000 mm^2/sec. Going into the vertex (the turn?) the speed was 38 so I assume the speed is 38 going out of the vertex. This means Y is going 19 (sin30*38) and X is going 33 (cos30*38). That's a lot of jerk at that vertex (X instantly 38 to 33, Y instantly 0 to 19 together comes out to 20mm/sec deltaV). We now accelerate X from 33 to 52 and Y from 19 to 30 (X deltaV is 19, Y deltaV is 11). X is still the limiting factor (it has to speed up more) so X accelerates at the full 3000 mm^2/sec but Y accelerates less 3000*11/19 or 1740mm^2/sec. This is important to keep the new line segment straight. E accelerates in a similar manner so that it is also linear (in a 4 dimensional straight line). The planner looks ahead about 20 lines segments because sometimes the vertexes are so close together that they never get up to full speed (or down to low speed) and you have to be able to round every vertex without going too fast. In other words, sometimes you have to start slowing down now because of a sharp corner (or a stop) 20 vertexes away. This method of defining jerk is not the best - I can add two points .1mm apart at a corner of a cube that turns a 90 degree corner into 2 45 degree corners .1mm apart. This will allow Marlin to go around that corner 40% faster yet it's also 40% more (true) jerk force on the hardware. It's a way to cheat/fool Marlin. In a bad way. Instead there should be a max jerk integrated over some small resolution. Maybe .2mm distance. But then the math probably gets more complicated. Another way to look at it - Marlin should be able to cut corners by some tiny amount - like .1mm or as that jerk isn't in theory infinite at each vertex (changing acceleration from 1000mm/sec to 1002mm/sec instantly is infinite jerk).

The mechanical assembly is trivial. It's the electronics that is tricky if you have never soldered before.

You printed too high off the bed. Any time that happens it's best to cancel the print immediately. The first layer is critical to keep it from lifting. If that happens you can grab the screw and spin it 3 clicks at a time until the bottom layer is looking good once again. Or you can halt the print and re-level.

I suspect nothing is wrong with your temp probe other than it slipping out. Being partly outside the heater block it was reporting a lower temp and so the heater compensated and overheated your nozzle.

I'm certain UM will send you one for free if you open a ticket at support.ultimaker.com. I believe it is a PT100 which is a platinum part that is 100 ohms at 25C. This is a very common part and comes in all kinds of shapes and sizes and they all have identical temperature versus resitance curves so you can replace it with any of those. you can't get the metal sleeve out without removing the long screw in the top of the heater block. But to get to that you probably need to take most of the head apart - it's not so hard though. Remove the fans (4 screws) and then twist the 4 long thumb screws and take them all the way out. At this point you can remove 2 screws to seperate the rear fan (hold it together while you remove as there is a spring which is quite obvious). Now you should be able to remove the long screw (need the right size hex driver) and then the heater and thermoresistor slide out.

The output at the top of the print head has a 3 pin connector which consists of ground (zero volts), power (5v I think) and a signal. The signal is 0v for 0C and 5V for 500C. So at room temperature it should read around 20C or 200mv. If this signal is correct at the top of the UM, test it at the PCB. If it is correct at the PCB then there is probably a bad solder joint that connects that signal to the arduino - just reheat both ends of the circuit. But more likely it seems you connect the wrong spare cable - the two cables are identical other than wire color. Where to get circuit diagram: ULTIMAKER1 The circuit diagram, and board layout are here: http://reprap.org/wiki/Ultimaker%27s_v1.5.7_PCB There is a zip file at the top. It contains the "brd" file which is the layout. Also the "sch" file which is the schematic. Both files can be opened by eagle software which is free: http://www.cadsoftusa.com/download-eagle/ ULTIMAKER 2 SCHEMATIC https://github.com/Ultimaker/Ultimaker2

Did you use brim? that might be enough. Or you can add several meshmixer supports: http://www.extrudable.me/2013/12/28/meshmixer-2-0-best-newcomer-in-a-supporting-role/

I'm pretty sure you simply need to enable retraction. It's a checkbox in basic settings. Also keep in mind that the slower you print, the better the quality (although the rest of the surface looks pretty good). So 30mm/sec looks much better than 60mm/sec and 20mm/sec looks even better. This is a constant tradeoff between quality and speed. But these strings I'm pretty sure will go away if you enable retraction.

You might also have underextrusion - it's difficult to change from ABS back to PLA - ideally you want to print at least a few meters of PLA at high speed and temp (240-250C) to get it all out. You can also use the "atomic" method but your photo doesn't show underextrusion - I guess I would have to see a lower level or a side view.

We usually call this "pillowing" and I'm not surprised it is worse with PLA. This is fixed (or greatly improved) with 100% fan. By default the fan doesn't reach 100% until 5mm up I believe (cura setting) so I would change it so that it is at 100% by the time it hits the top layer fill - 1mm is a good value for this typically as it allows the fan to come on slowly over 5 to 10 layers (depending on layer height). Also doing more layers will help. 1) What is the thickness total of your part? 2) What is your top/bottom thickness? Pillowing example: http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/?p=17300

Two things: 1) I think it's more reliable with the filament on the floor for several reasons I don't want to get into. 2) If a print fails part way through (say after 6 hours or 20 hours) don't let the bed cool - if you have to hit power then that is fine but turn it right back on and keep the bed warm so the part doesn't pop off. You can leave the bed at 60C (or whatever) for several days until you know what to do to continue the print. It's not too hard to continue the print. Let us know and I'll find the directions to how to do this. filament on floor:

Non printing moves. Yes. Also if there is a vertical blue line that is a way to represent "retraction". Retraction is used when printing between 2 or more "islands" in a given slice.

If you end up doing a compression test on a scale, photograph the spring, tell me the length uncompressed of the spring, tell me the force at a given length (for example compress it to say 15mm length and measure the "weight" on a scale) then I will repeat your experiment on my (much too strong) spring and we will have at least one, but maybe 3 ways to tell them apart. I'll even tell you the force the spring makes when the feeder is at the top position. But be warned - if you take the feeder apart the stepper will fall. Not a big deal but an extra thing to worry about.