gr5

You are asking about marlin *and* cura. That's a lot to cover. If you build a custom printer you need to create your own Marlin. You can set Marlin to use software endstops or hardware endstops. If you are lucky you can build marlin using this convenient web page: http://marlinbuilder.robotfuzz.com/ If it doesn't have all the settings you need then at least use that page to build a starter configuraion.h. Either way I recommend you look at the configuration.h it generates and read all the comments to make sure it's "good enough" for your printer. Cura In Cura there are "machine settings". You can go in there and set the dimensions of your machine and cura will let you print bigger. Cura will by default place objects on the center - in other words if your build area is 300X300mm it will place it at 150mmX150mm but you can just drag the object around if you want. Or place multiple things. The settings about "minx", gantry height only affect if you want to print multiple objects "one at a time". You can skip those machine settings for your first print.

Sitting by the printer and watching it change is a lot of wasted time. Instead look at the gcode. Gcode is easy to read - it's meant to be read by computers *and* humans. It has lots of comments about layer number in there and so on. The fan command is M106. The "S" number after that is the speed where 0 is 0% and 255 is 100%. While in the TUNE menu and looking at the fan speed maybe it's possible it won't change? More likely I think you found some bug. I never set min fan speed to anything other than 100% because I don't print ABS much but maybe you found a bug. What it should have done instead is start off like you said but turn on GRADUALLY until by layer 2mm it is at 60%. 34% maybe around layer 1.2mm and it might have been stuck because that's when you entered fan menu settings within the tune menu? And that action may have locked the speed. Check the gcode - it's much easier. Search for M109 and you can see right there what layer it is modifying fan speeds on in the comments.

Yes - lower bed temp. This is a problem I've talked about quite a bit now. It's because for smaller parts they don't have enough time to cool and so the "base" layer that you are printing onto is still too soft and the upper layer pulls it and "warps" it. Printing slower might help for the bottom 5mm or so to give it more time to cool. Above 5 or 10mm it's not a problem as the air is cooler. Fan will help also. 60C is probably good enough for you. I found that for getting parts to stick to the bed 40C to 80C seems to be all about the same but somewhere around 30 to 35C there is a sudden transition where parts don't stick as well because the plastic doesn't flow as well to make good contact.

@abstract - the feeder motor is almost always off when not printing. Before i start a print I simply grab the filament 20mm below the feeder and slide it upwards. The retraction amount is normally 4.5mm but there is also an end-of-print retraction that is 20mm. But it's supposed to unretract that at the start of the print but for you I think it's getting caught on your teflon piece.

After thinking more about why Daid did this in the first place, I have a cura fix idea. The original problem was that combining these short segments (removing intermediate move points) into slightly longer moves on corners is that when you do the long edge move (the side of the square) sometimes it starts .05mm off from the layer above or below and you get a slight indent along that line - looks kind of like under extrusion. .05mm is more obvious when it affects 20mm of a print line. The fix is to go back to the old threshold but only combine line segments (only drop intermediate travel points) if all of the line segments are each shorter than say 3mm. That way you won't combine a short move with a long move thus causing the problem that was occurring in cura 14.01.

Okay - so the problem was kind of obvious once I sliced this file using both Curas and then opened the gcode in repetier host. The STL file has about 60 edges along the curved corners. Some of these edges are about 1/10 as wide as others in a seemingly random pattern. The older Cura had a feature where it would just skip over line segments that were shorter than a particular length - probably around .1mm, but the new Cura lowered that threshold by quite a bit due to demand from users like us because of complicated results related to rounding errors. I think the original threshold was better. The reason 60 edges on a corner is a problem is that Marlin only has enough computing power to plan out about 10 edges in advance (or maybe it's 20?) and so it has to be ready to come to a complete stop after 10 edges because it doesn't know what's next so it starts decelerating maybe 10mm before then but with 60 edges taking up 3mm Marlin slows the hell down - probably to around 10mm/sec around those corners. Slowing down from a typical printing speed to 10 or 20mm/sec causes some overextrusion on those corners. In the photos below the yellow portion on the left is the same as the highlighted portion on the right - the 14.03 photo (lower photo) has 32 line segments in that yellow portion and some are as short as .05mm!! The 14.01 photo has many fewer line segments as cura tossed out the short ones: The obvious fix is to go to your CAD software and in the STL export settings there should be a way to specify the resolution on curves - something like that. Tell it not to output triangles smaller than say .2mm across (that's the radius of the nozzle and in one sense you can't really print finer than that anyway without getting a smaller nozzle). There's probably some "max resolution" or "min resolution" or something that affects this. Also maybe Daid should set the limit back to where it was. Also there will be future Marlins that run on faster processors - actually Eric Zalm is working on this now and so the UM3 will hopefully have an ARM processor which can look out 100 line segments instead of 10 and maybe there will be a UM2 and/or UM Original upgrade. But this is a ways off.

The blue tower is definitely underextruded. You could have saved time and filament by only printing for the first 10mm. What temp were you printing at? There is a relationship between speed and temperature. 80mm/sec .2mm layers is (I can do this in my head: 80X.2X.4) 16mm^3/sec which is - well - INCREDIBLY FAST. I think even at 240C you won't be able to do that - that's kind of beyond the printing ability of most Ultimaker2's. However if that is .1mm layers then you are at 8mm^3 per second which is kind of near the limit of what a UM2 can do. I can do that if the filament is at 240C. Barely. Better at least than your results. If you really need to print 80mm/sec and .1mm layers you need to crank up the temp - 250C might be best. Don't use 250C when printing slow though or you can "burn" the filament.

This test isn't about quality - it's about how much plastic can you force through the nozzle in a second before the extruder motor slips backwards. It's checking to see if you have something wrong with your extrusion path (feeder, bowden, head, nozzle) this is not achieving normal ability for a UM2. It looks like your printer is doing pretty well. I'm not sure what that means. I guess that must refer to the temperature as I don't think there are any other settings that affect this speed test.

Well this is heating up in the last few days - or maybe just yesterday. It appears Makerbot just filed a slew of patent applications including at least 2 different ones that take designs from the community. Including my favorite thingiverse inventor known as emmett. One design even talked about by makerbot thanking the designer of this wonderful improvement and then going on to patent it!: http://traverseda.wordpress.com/2014/05/23/makerbot-blatently-steals-and-patents-a-community-design/ Even slashdot. Slashdot! Mentioned it. Wow: http://yro.slashdot.org/story/14/05/23/2133237/questionable-patents-from-makerbot Another patent is for automatic bed levelling using the head as the probe first posted by the community (not electronically probing - mechanically - it's an interesting design - but from the reprap community).

Wow. Must have taken you all day, lol.

There was a time when vista came out and it was much too slow on most computers out there and even brand new computers were shipping "vista ready" but where much much underpowered to run vista. However, the hardware has caught up and surpassed this issue years ago. Hardware gets about 2X faster every 1.5 years. Pretty much all computers sold today can handle windows 7 (or 8) and can handle cura and will be at least 5X than 90% of computers sold from the XP era. Worry more that it can read/write SD cards, does it have SVGA output or only DVI or HDMI output, stuff like that - obvious tangible things.

Please update your location as to your country in your profile settings. If you are in USA I can give you some links to some "bowden material".

Could you send me the STL of this "box with rounded corners" please? I want to do some tests. I want to use your exact box that has problems. You can email it to - lets see - here's a temporary email: gr-tempjan06 _at_ spamarrest.com Change the _at_ to the @ symbol. And remove spaces.

There is some kind of "hop on move" setting or something where it moves the Z up - does that make a difference?

Nylon sucks in moisture amazingly. When you print it you hear a constant crackle. It creates thousands of tiny holes which refract light and make clear nylon look cloudy. It does *not* make black spots. Those black spots are something different. I don't know that ABS absorbs much moisture. I'm not sure what made the popping sound. Maybe you had a partial clog of some sort where pressure built up. The feeder on the UM2 is made of black ABS and pieces of it can move along the bowden and come out into your print. Also ABS is very sensitive to overheating - I recommend 245C for ABS for beginners. I am also an ABS beginner - but I have read about 10,000 posts on this forum so I know a little. ABS will turn brown or black if heated a long time or high temp. I suspect 240C at 4 hours is plenty but not sure exactly.

Please don't post questions or please limit them in this topic. For one reason - I only come to this topic once a week and it's to see beautiful prints and be inspired. I love to help people quickly so other topics I look at twice a day - I know - there's something seriously wrong with me. For another reason, there are so many posts here that your question will get lost or if you ask 4 questions only one will get answered. Posting a beautiful print along with "can I stain this?" is fine but asking about underextrusion or overhangs or mesh problems - well it's fine to ask but you'll get better answers elsewhere.

Here is that screw I was talking about - it holds the temp sensor and heater in place:

Did you complete step 7 above? That screw is holding in the temp sensor and heater. If you can't get the screw out with a hex wrench, just use vice grips on the tip of the screw. Once that is out you can get the temp sensor and heater out. If they seem stuck just use pliers and get a good grip right where they enter the heater and gently twist and pull. You might need to do this while the heater is hot but not on. I did it while the head was at room temp. They slid out without needing pliers.

Aaron means the "TUNE" menu. By layer height .4mm I guess the fan should be at 20%. I never have tried less than 1mm for full fan so maybe there is some kind of bug? 20% is kind of low - sometimes the fan won't come on until it hits 25 or 30% so I'm not sure why you want 20%. I recommend 100% for PLA. If fan min is 20% it should start at 0% first layer and hit 20% by layer .4. It only goes to 100% if it can't meet the minimum layer time. If you set fan speed in TUNE menu this overrides the fan speed from the gcode (at least until the next gcode changes it again but once at 20% it might stay there for the whole print).

Usually temp issues with UM1 are resistance (almost an open) in the cable at the top of the print head. There is a 3 wire cable running from the small circuit board on the head to under the machine. The problem is usually the wire above the top of the head. At room temp (any temp really) try pushing the head around to the 4 corners and watch the temp to see if it jumps suddenly. Also try poking the wires until the temp jumps. If this happens just switch to the alternate cable (meant for a second extruder) or replace the wiring. FYI, the voltage coming out of the circuit on top of the head should be 0V for 0C and 5V for 500C and linear in between so 20C should be around 200mv. If this voltage is wrong (and the 5V to the chip is correct through that 3 pin cable) then the problem is with the thermocouple. But this is rare - usually the problem is with the cable on top of the head.

No, not the "shell" setting in Cura. The actual part you are printing. Cura can not print walls thinner than the nozzle and sometimes maybe not even walls under 1mm thick. It *REALLY REALLY* would be helpful for you to post a photo of the part in normal view and layer view. Here is how to post pictures: http://umforum.ultimaker.com/index.php?/topic/4525-how-to-upload-an-image-to-the-forum/

Maybe - some UM2 fan cables (a lot! maybe 20%?) got disconnected during shipment. So they might not run at all. Or they might run backwards. I suspect they are fine and you just need to make a thicker top or more infill but to test the fans on UM2 (or do you have UM1?): Select PRINT (even though we won't be printing), choose anything on the SD card. Then immediately go to TUNE menu and go down to fans and set to 100%. Test that they are both spinning and that they are blowing downwards. The printer will not start printing while you stay in the TUNE menu but if the nozzle is heated up when you exit it might start printing so once you exit do an ABORT. Or you can just kill the power.

lol. Me too, but I didn't want to be too rude about it. I wanted to motivate him to look at the gcode.

When looking at your settings the HUGE RED FLAG was that your shell was 1.0mm instead of .8mm or 1.2mm this causes either 3 passes of .33mm undextrusion (good) or 2 passes of .5mm attempted overextrusion (bad). Either way try .8 or 1.2mm (a multiple of nozzle diameter). Other than that it looks like basic underextrusion issues of which there are many causes. It would help to know if this is a um1 or a um2 as they have very different causes of underextrusion. The simple fix is to just print slower and/or hotter. Underextrusion is when the feeder can't apply enough force to get that thick plastic through that tiny nozzle. The problem may be the nozzle or the feeder but it's easiest to just raise temp to 240C where the plastic flows more like honey than toothpaste and/or slow down the print by 2 or 3X to say 35mm/sec. But if your machine is partly broken (can't extrude like it used to) then start off by characterizing your machine here: http://umforum.ultimaker.com/index.php?/topic/4586-can-your-um2-printer-achieve-10mm3s-test-it-here/ The above is a useful test for UM1 also. And make damn sure you print at the standard test setting of 230C otherwise the test result you get will be meaningless.

By the way it should be accurate to about 1C and even an error of 3C is not a problem but 20C is bad. It should be just as accurate at 20C as at 200C.