gr5

Hi guys! I didn't see this thread. It should *not* drop to 62C. Maybe it drops when the nozzle first comes on but once the nozzle is up to temp the bed should rapidly (within 30 seconds) reach back to 75C. I've printed ABS with the bed at 100C no problem. My nozzle heater is 40W. I think the problem is the firmware you got from tinkerGnome probably has some bug in it. I wrote the firmware for the um2go hbk and it was tricky code. tinkerGnome doesn't really have a need or a way to easily test it. So I urge you to get the firmware here - the "tinker 16.02" version with my special updates: http://gr5.org/hb/ It's possible that there are no bugs in tinkerGnome's version but that's the most likely thing right now as I can keep my bed above 100C easily. I've printed ABS with my um2go many times - in fact that's my main ABS printing machine as it heats up so much faster than the UM2.

Well I think the important setting in this case was print speed.

You need to specify cubic, not squared. So multiply by the print speed as well to get volume. 8mm^3/sec and 230C is where UM2's are tested but you are really pushing it there. UMO can do that just fine also. Here's a speed guide table for both UMO and UM2. Here are my recommended top speeds for .2mm layers (twice as fast for .1mm layers) and .4mm nozzle: 20mm/sec at 200C 30mm/sec at 210C 40mm/sec at 225C 50mm/sec at 240C The printer can do double these speeds but with huge difficulty and usually with a loss in part quality due to underextrusion. Different colors print best at quite different temperatures and due to imperfect temp sensors, some printers print 10C cool so use these values as an initial starting guideline and if you are still underextruding try raising the temp. But don't go over 240C with PLA. Now if you want high quality looking parts you want to keep speeds in the 20mm/sec (super high quality) to 35mm/sec (excellent quality) range regardless of layer height because faster than this causes ugly overextruded blobs here and there. These slow speeds keep the nozzle speed constant and the nozzle pressure constant (or close to it) which makes for a nice uniform extrusion.

Wait - you compared UM2+ versus the "delicious clam"? Or versus stock um2?

The "bowden holder" looks good enough to me but I'm not an expert (maybe the metal parts should be angled the other way?). very nice photography by the way! If you buy a teflon part then get the clip also (I sell both) but I wouldn't buy a new bowden - just cut a few mm off the one you have so the "bowden holder" can get a grip on some fresh bowden.

Make sure you slice in "reprap" mode in cura when you create the gcode (not "volumetric" nor "ultigcode" modes). It's in the machine settings.

So Artiz - when you said you had the "same problem" I was skeptical. But after reading your summary I trust your debugging more - does it still seem to be the same? If so it's probably the same solution (new PCB). But I guess you know that.

Thanks Artiz for the great summary and welcome to the forum as this is the first I've noticed you (or maybe you changed your icon recently - sorry if I'm noticing you again). I hope you help more people in the future.

Oui! Absolument! Trouver quelqu'un ici sur 3dhubs avec le ultimaker2 (le ultimaker2+ que la qualité ne sera pas pire). http://3dhubs.com

He got help up until we were totally confused and had no answers. Artiz did you check for dirt/pla chunks holding the switch down? Does pronterface let you move the Z? If you swap X and Z cables does the Z move but not the X? Do you have a UM2?

What IRobertI said - listen to him! I've repaired many bowdens. I sell the clips alone if yours is broken. They are pocket change: http://gr5.org/store/

I just use soap and water about once per month. 1) Make sure the glass is clean if you haven't cleaned it for a few weeks. You want a very thin coat of PVA glue which is found in hairspray, glue stick, wood glue. If you use glue stick or wood glue you need to dilute it with water - about 5 to 10 parts water to 1 part glue. So for example if you use glue stick, apply only to the outer edge of your model outline then add a tablespoon of water and spread with a tissue such that you thin it so much you can't see it anymore. wood glue is better. hairspray doesn't need to be diluted. When it dries it should be invisible. This glue works well for most plastics. 2) Heat the bed. This helps the plastic fill in completely (no air pockets) so you have better contact with the glass. For PLA any temp above 40C is safe. I often print at 60C bed. 3) heat the bed (didn't I already say that?). Keeping the bottom layers above the glass temp of the material makes it so the bottom layers can flex a bit (very very tiny amount) and relieve the tension/stress. For PLA 60C is better than 50C. 70C is even better but then you get other "warping" like issues at the corners where they move inward but if you are desperate it's worth it. For ABS you want 110C (100C is good enough). 4) rounded corners - having square corners puts all the lifting force on a tiny spot. Rounding the corner spreads the force out more. This is optional if you use brim. 5) Brim - this is the most important of all. Turn on the brim feature in cura and do 10 passes of brim. This is awesome. 6) Squish - make sure the bottom layer is squishing onto the glass with no gaps in the brim. The first trace going down should be flat like a pancake, not rounded like string. don't run the leveling procedure if it is off, just turn the 3 screws the same amount while it is printing the skirt or brim. Counter clockwise from below gets the bed closer to the nozzle. Don't panic, take a breath, think about which way to move the glass, think about how the screw works, then twist. This may take 30 seconds but it's worth it to not rush it. You can always restart the print. If you do all this you will then ask me "how the hell do I get my part off the glass?". Well first let it cool completely. Or even put it in the freezer. Then use a sharp putty knife under a corner and it should pop off.

The thinner the strings, the easier they are to remove. Very very thin strings can be removed with a candle flame but be very very careful.

Wait - so you can move all the axes with printrun? And you can set the temperature and it heats up? And when you tell it to home it homes? But it won't print? Is that what you are saying? I mean - sure - the ulticontroller is worth the price I think.

It's just cut and paste. Keep swapping gcodes until it works perfect and then go back to the newer gcodes until you find out what is causing the problem.

You don't show the more important end of your white teflon part. You probably need to change it anyway. I have them cheap here: gr5.org/store/ Also your bowden has lots of scratch marks and I think it's slipping. Inspect the white part with the 4 metal blades that holds the bowden in and make sure the 4 blades are still there. If they are then great. Then cut off about 3mm off the end of the bowden so the blades can grab the bowden at a fresh new spot - you can't have that bowden sliding up. That can cause those mushrooms you speak of.

Either the motor is not connected well to the z screw or the motor is not as strong as it should be or the bed is more stuck than it should be. First check for smooth travel. With power off slide the bed up and down - grip it near the back with both hands. It should be able to go up without lifting the UM2 off the table much. Make sure it doesn't hit the spool holder which passes through the back wall and can sometimes hit the bed. Maybe send us a video of the issue. Some newer PCBs that come with the printer had a problem with the Z extruder. They lowered the current for that extruder I believe and that makes it less likely to overheat and it works better that way.

>but could have stability issues regarding communication with the computer. Well, yeah. If your prints stop suddenly for no reason - try a different computer with hopefully better usb. Or try a usb buffer or a different usb cable. Or try coiling the cable? But for many people it's very reliable. Somewhere in cura (and printrun?) there is a log file that tells you how many transmitted lines of gcode failed! This can be 90% If you have that then it's a problem waiting to happen. If it's 0.1% then don't worry.

You can print fine without the utlicontroller. but don't use cura for the calibration step - just skip that wizard. You can cancel it and continue with cura. Calibrate it by homing Z only and push the head around and use paper and turn the screws. I recommend pronterface over cura for controlling your printer. The feedback and control is fantastic and much simpler than cura. It's a free download here: Get pronterface here. It's free: http://koti.kapsi.fi/~kliment/printrun/ But use cura for creating the gcode files.

Did you print this out of PLA? doesn't it melt near the nozzle?

Yes cooling helps. The more cool the better. You want fans at 200% if there was such a thing. Add a desk fan? There's a huge discussion about this. *while* it's printing if you look at ti carefully you will see the edge of the front of the boat is raised and the head hits this edge. More talk about it here: http://umforum.ultimaker.com/index.php?/topic/4094-raised-edges/ Skip right to "page 2" and look at foehnstrum's video and read all the posts after that possibly. It's not until around post #39 and later that we really begin to understand what causes the issue. The problem has to do with the fact that liquid PLA is stretchy like melted mozzarella cheese or like mucus. The liquid plastic is pulling like a rubber band as it goes down and creates a lip or raised edge where there is an overhang. The effect gets stronger on each succeeding layer. It is what causes the lower quality "look" of overhangs. Sometimes the part will actually rip free from the bed because of this (which is easily fixed by making parts stick like hell - another topic). Also printing super slow (5mm/sec) can help as it remelts the layer below. Any faster than that speed and it doesn't seem to make any difference. This is talked about in the topic above.

What? New development? The advance stuff has been around for years and some printers use it routinely (they need it!) but I haven't heard about any *new* development.

You need to start over and throw all your assumptions out (e.g. "I know it's not the _____"). As far as underextrusion causes - there's just so damn many. none of the issues seem to cause more than 20% of problems so you need to know the top 5 issues to cover 75% of the possibilities and 1/4 people still won't have the right issue. Some of the top issues: 1) Print slower and hotter! Here are top recommended speeds for .2mm layers (twice as fast for .1mm layers) and .4mm nozzle: 20mm/sec at 200C 30mm/sec at 210C 40mm/sec at 225C 50mm/sec at 240C The printer can do double these speeds but with huge difficulty and usually with a loss in part quality due to underextrusion. Different colors print best at quite different temperatures and due to imperfect temp sensors, some printers print 10C cool so use these values as an initial starting guideline and if you are still underextruding try raising the temp. But don't go over 240C with PLA. 2) Shell width confusion. Shell width must be a multiple of nozzle size. If nozzle size is .4mm and shell width is 1mm cura will make the printer do 2 passes with .5mm line width which is possible but requires you slow down much more to make a .5mm line out of a .4mm nozzle. If you really want this then set nozzle size to .5mm so it's clear what you are asking Cura to do for you. 3) Isolator - this is most common if you've printed extra hot (>240C) for a few hours or regular temps (220C) for 500 hours. It warps. It's the white part touching the heater block. Test it by removing it and passing filament though it by hand. Also if you notice parts of it are very soft then it's too old and needs replacing. 4) Curved filament at end of spool - if you are past half way on spool, try a fresh spool as a test. 5) curved angle feeding into feeder - put the filament on the floor -makes a MASSIVE difference. 6) Head too tight? Bizarrely MANY people loosen the 4 screws on the head by just a bit maybe 1/2 mm and suddenly they can print just fine! Has to do with pressure on the white teflon isolator. 5b) Bowden pushing too hard - for the same reason you don't want the bowden pushing too hard on the isolator. 5c) Spring pushing too hard. Although you want a gap you want as small as possible a gap between teflon isolator and steel isolator nut such that the spring is compressed as little as possible. 7) clogged nozzle - the number one problem of course - even if it seems clear. There can be build up on the inside of the nozzle that only burning with a flame can turn to ash and remove. Sometimes a grain of sand gets in there but that's more obvious (it just won't print). Atomic method (cold pull) helps but occasionally you need to remove the entire heater block/nozzle assembly and use flame. Or soak it in acetone overnight (after removing 90% of the material with cold pull). 8) Temp Sensor bad - even the good ones vary by +/- 5C and bad ones can be any amount off - they usually read high and a working sensor can fail high slowly over time. Meaning the sensor thinks you are at 220C but actually you are at 170C. At 170C the plastic is so viscous it can barely get out of the nozzle. You can verify your temp sensor using this simple video at youtube - on you tube search for this: mrZbX-SfftU 9) feeder spring issues - too tight, too loose 10) Other feeder issues, one of the nuts holding machine together often interferes with the feeder motor tilting it enough so that it still works but not very well. Other things that tilt the feeder motor, sleeve misaligned so it doesn't get a good grip. Gunk clogging the mechanism in there. 11) Filament diameter too big - 3mm is too much. 3mm filament is usually 2.85mm nominal or sometimes 2.9mm +/- .05. But some manufacturers (especially in china) make true 3.0mm filament with a tolerance of .1mm which is useless in an Ultimaker. It will print for a few meters and then clog so tight in the bowden you will have to remove the bowden from both ends to get the filament out. Throw that filament in the trash! It will save you weeks of pain 11b) Something wedged in with the filament. I was setting up 5 printers at once and ran filament change on all of them. One was slowly moving the filament through the tube and was almost to the head when I pushed the button and it sped up and ground the filament badly. I didn't think it was a problem and went ahead and printed something but there was a ground up spot followed by a flap of filament that got jammed in the bowden tube. Having the "plus" upgrade or using the IRobertI feeder helps you feel this with your hand by sliding the filament through the bowden a bit to see if it is stuck. 12) Hot weather. If air is above 30C or even possibly 25C, the air temperature combined with the extruder temperature can soften the filament inside the feeder such that it is getting squeezed flat as it passes through the feeder - this is obvious as you can see the problem in the bowden. The fix is to add a desk fan blowing on the back of the printer. Not an issue on the UM2 "plus" series. 13) Crimped bowden. At least one person had an issue where the bowden was crimped a bit too much at the feeder and although the printer worked fine when new it eventually got worse and had underextrusion on random layers. it's easy to pull the bowden out of the feeder end and examine it. 14) Small nozzle. Rumor has it some of the .4mm nozzles are closer to .35mm. Not sure if this is actually true. I'm a bit skeptical but try a .6mm nozzle maybe.

ditto? Is there a ditto gcode? It uses I think T0 and T1 (tool zero and tool one) to switch nozzles.

This is also a great use of the .25mm nozzle to get fine lettering.