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I've never seen that error. What version of Marlin do you have? That's a new feature I think. I would open the CURA file in a text editor and search for PLA on the first few lines and change it to PLAf and also change your material name to PLAf and see if that helps. This really looks like a new bug/feature. it could be related to a known bug in marlin talked about here and easy to fix but I doubt it: https://ultimaker.com/en/community/19700-what-are-the-various-parameters-in-the-materialtxt-file?page=last#reply-136309 Read tinkergnome's posting and note the bold parts and then read the first posting. Alternatively get rid of that space between "PLA" and "flex"?

Oh yes. Of course. But we are biased here. The quality is the best - I've been to many shows and I think the UM printers have the best quality of all fdm printers. But is print quality really the most important thing? The driver/motor pairing issue - there are also resistors and other parts that are involved in this marriage. Some combination is a bit off on some (all um2?) printers. But it's really subtle and you need obscure prints like a wall that is not square to any axis but *almost* square to 2 axes to get this. This is very rare in any print. But Benchy has this rare situation. None of my thousands of other prints have this situation I believe.

>The 1% being one of the corners lifted ever so slightly. Shouldn't happen. Did you remember to clean it with isopropyl alcohol? I've had tape come off the glass but never part come off the tape. Again you need to squish it a bit just like with glass to get in the nooks and crannies of the tape. I can't see how fan could possibly make wall-cave-in worse.

Cura doesn't set the acceleration - it's purely in Marlin (the firmware inside the printer). I believe you can see the value in "motion settings" or something similar in the Menus on the printer itself.

It's also possible that the X motor is skipping steps. This is much less likely but it can happen. Usually only if X axis has much higher friction than Y. That can happen if the end caps are too tight or if it needs a drop of oil on the long rods. Feel the friction for X versus Y. Are they about the same? If so then it's probably fine. Still consider loosening one screw on one one endcap for each of the 2 rods that spin for the X axis movement.

I watched the first 1:12 and I now think it's slipping in the X axis. This is very common but usually it only slips in one direction but you have it slipping left *and* right. Not impossible. So it's almost always caused by one of the pulleys not tight enough. There are 6 (SIX!) pulleys on the X axis (not 4). The most likely ones to be slipping are the 2 on the short belt. You should be able to tighten them hopefully without loosening the motor screws if you have the right too. Maybe. I forget. Anyway you have to really tighten the hell out of those set screws. Enough such that the tool twists a bit. Enough that it hurts your fingers if you have an L shaped wrench. UMO often comes with a second set of set screws that are silver instead of black - the silver ones are pointier and supposedly better. I didn't realize this and I still have my black set screws and they are fine but boy do you have to tighten the hell out of those.

Is it AC or DC? AC power vibrates your muscles like a buzzing. It's what comes out of your house power socket. DC you can't feel unless it is thousands of volts. Caused by static electricity which could come from any moving parts (like the printer - it moves). If it's AC then it's easy to measure with a volt meter. For example you may have bad wiring in some of your home or work power sockets such that some are wired backwards. You could put one end of the voltmeter on a ground like a metal water pipe and the other on various parts of the Ultimaker. If you get 200 volts then that's a problem and try plugging it into other outlets or call an electrician as your power outlets may be backwards.

Oh - and blue tape is actually a reasonable option for you. But it's critical that you clean the blue tape with isopropyl alcohol to get the wax off the non-sticky side of the painters tape.

Because your machine is covered - try lowering the bed to 50C. The PLA should stick just as well. I did experiments where I did a 2 minute print (the bottom 5 layers of the ultimaker robot) about 20 times with different settings. I used a scale and a screwdriver to push the part off the bed (while bed was still hot) and measured the force. I tried glue/noglue. I tried hairspray. I tried many different temperatures. There was a huge difference around 35C where cooler than 35C and the part came of with about 1/10 the force. After that I never print with bed cooler than 40C. 50C should be quite safe - well above that critical threshold. The next threshold is around 60C to 70C where you are above the glass temp of PLA and if you can keep the bottom 2mm of the part above glass temp you get horrible "wall cave in" but you get zero "lifting off bed" problems. You don't want wall cave in" so once you are down to 60C there isn't much "down side" to going even cooler to 50C as you are now below glass temp of PLA anyway. Finally another completely different option - you could print the bottom 5mm of the part at 190C and at 1/4 speed and then speed it up when you are well past the "wall cave in" area. If this works you can hand edit the gcode or use the "tweakAtZ" plugin to change temp and/or speed at a given Z height.

Photos please. Also do you have an opaque color? Preferably not black or white but somewhere in between? Gray shows up details the best (or almost any color that isn't close to black or white).

This is very common after installing the olsson block and usually happens when the fans come on which is typically the second or third layer. The problem is that the olsson block is touching the fan shroud somewhere. I would start heating the nozzle to 150C (in case there is plastic in the threads) and then remove the front left thumb screw so you can get good access to the round nut that positions the olsson block height. Also remove the 4 screws that hold the fan shroud and let that hang down by the wires. Now make sure the nozzle is above 140C and rotate that round nut using something metal, long and skinny. Like a very small screw driver. Rotate it both ways a bit to make sure it isn't at the end of travel and then rotate it such that the olsson block moves up as high as it can go or possibly 1/2 turn less. This whole thing was designed for when you have dual nozzles and you need to get them the exact same height within .01mm. Since dual printing never worked you want the nozzle as high as it can go so the olsson block doesn't touch the fan shroud. Consider possibly putting a thin strip of kapton tape on the bottom of the olsson block to give it a little bit of insulation between it and the fan shroud. when you put the fan shroud on push down on it while tightening the 4 screws that hold it on. Even getting another .1mm might be enough to get rid of your "heater error". Test it by heating to printing temps (say 220C) with fans on 100%. It takes 30 seconds without the nozzle heating up to get the error. Alternatively get a more powerful nozzle heater - UM2 used to come with 25W heater but some of them are as low as 18W due to manufacturing variability. Get a 35W from 3dsolex or Ultimaker.

It has an aluminum cylinder that replaces the spring but if you don't tighten the round nut enough (which raises the olsson block) then there's too much pressure on the teflon part. Oops - I guess it would be a problem if you tightened it too much.

[print=3785][/print] Made this for daughter's boyfriend who will be gifting it to his boss soon. Now everyone who has seen it wants one of their own, lol.

Let's start over - now that I've finally seen a photo of your 2 problems. For wall cave in you need to cool things down - usually the bed is enough but maybe you should cool down your nozzle temp also. Also get that fan going by .5mm off the bed. For sticking to the bed you need to add brim. It sucks when you want to glue two pieces together but if you have the right tools (razor blade, mini set of files) it's really not so bad to remove the brim after. And you need PVA glue and you need the bed above 40C and you need the nozzle slightly closer to the bed (squish that bottom layer in there good!). There is a compromise bed temp - the cooler it is the less "wall cave in" you will get. The hotter it is the less you have to worry about "corners warping up off the bed". For most of us that is 60C. At 75C you get zero "lifting off the bed" but horrible "wall cave in" but if you can get it to stick like hell (PVA, brim, squish) then you should be able to get by with 50C or 60C bed temp.

I think it's the stepper *driver* and not the motor that causes this. There's pages of math that comes with the driver that explains how *not* to get these and it involves picking the right resistors (and capacitors) for your particular application depending on all kinds of properties of your power supply and the stepper motors and possibly inductance of the motor and so on. If you don't get it just right you get uneven steps (smaller than desired steps for 15 microsteps and then larger than desired for 1 microstep, repeat). I read it all and still didn't understand it fully - it really needs 20 hours of careful reading/study and I don't think it can be explained in a few minutes. Trying to picture how offset AC sine waves passing through 2 different coils at slightly different phases even gets the motor to move a sub step baffles me already let alone this detail of why it substeps too far occasionally... I don't quite get the issue in the first place - just that it exists in the industry and that there is a way to ameliorate it mostly (but maybe never fully?). Really these printers should all be using servos and not steppers.

If that's the problem try loosening the 4 thumb screws on the heat a turn and the problem might go away.

Oh and "raft" will likely help but it will make the bottom of the part very ugly and you wont be able to glue it together. "raft" is an older technology and no one uses it anymore now that we have newer technologies like blue tape and after that, then heated kapton, and now we are at heated glass - the best I've seen so far (although there is "build tak" which is even newer but I'm not convinced it's better than heated glass). The raft warps/bends and so the part can shrink the tiniest amount and not lift off the glass and still be dimensionally accurate.

"wall cave in" is what jechsturk replied to your very first post Ronan. He called it "elephant foot". It is caused by the bed being too hot. When printing PLA it cools extremely rapidly as it comes out of the nozzle shrinks within milliseconds and acts like a liquid rubber band for a short period before it freezes - like snot. So corners are pulled inwards hence "wall cave in". Simply lower your bed temp another 5C to 55C and this should go away completely. Getting your part to stick is best done with brim but if you don't want to use brim just loosen the 3 screws on the bed 1/4 turn (.025mm) moving the bed closer to the nozzle slightly. Possibly also start over with the glue - you want a very thin layer of PVA and dust may have accumulated over the past few days. It really sucks that I can't see any of your pictures except for one now - it's really best to use the "image gallery" button (2nd from right) above where you create the post and not "add external image". It's also a bit rude to post a photo from some image website that may drop the picture after a few days/weeks/months/years whereas Ultimaker will host your photo as long as they host this topic.

What? This sounds very new. What version of Cura are you using? How do you set PLA in Cura? I've never seen that before. One workaround - print it with any material settings, then while the printer is heating up, go to the TUNE menu and change the settings to whatever you want. It won't start printing until you exit the TUNE menu. Another workaround - change the values for PLA then do SAVE SETTINGS then choose PLA after you save. This will change the settings for PLA. I like the first workaround better. But... what version of Cura do you have?

Your bottom layer is bad. You need the nozzle closer to the glass. You want the plastic squished more. The leveling procedure that comes built in is not so good - it wants you to level the nozzle perfect such that the first layer is printed .3mm thick with the nozzle .3mm off the glass. But you get better results if the nozzle is closer than this. There should be no gaps in your brim - I see gaps between every pass of the brim in some spots. So just turn the 3 screws of your bed by a half turn counter clockwise to raise the glass towards the nozzle and try again. Watch the first layer carefully and adjust the corners that seem too thin or too big gaps. It takes practice to turn the knobs on the fly but if you do it on every print (just for practice and good habit) you quickly become an expert. Also after a few prints you end up with a bed that never needs leveling again.

Well if it's only on the older machines I would highly suspect the teflon isolator (the white part in the head) and the bowden as those 2 parts can wear out. Most likely the teflon part. Also Ultimaker (and 3dsolex) now sell a better kind of higher temp teflon and stopped selling the older (more opaque) white teflon parts. I had an absolutely brand new um2 extended that did this. It was easily solved by increasing flow by 10% but it drove me crazy. I tried many things but never figured it out and I had to return the printer (it was a loaner from Ultimaker). But just increasing the flow to 110% worked fantastic so I lost some of my motivation to figure out the problem since it was printing so well with 110% flow.

Don't get hairspray into your printer (it's glue!). Instead either remove the glass or spray onto a tissue and then wipe it onto the glass.

What kind of stepper drivers does the wanhao dup 6 use? I'm pretty sure we concluded above that the problem is how the stepper drivers are hooked up (the various resister values and so on).

Yes. I just microwave a mug of water until it boils. Pull it out, put a thermometer in it and then dip some unprinted filament into the water pushing against the sides. Find where it starts to get soft and make a note of the temperature. You want the heated bed a little above that temp (5C to 10C above). The higher the softening (glass) temperature the more difficult the material is to print unless you enclose the printer (heat the air). But a higher glass temperature is also an important property for many uses as a car with windows rolled up in the sun on a hot summer day will destroy all your PLA prints. Any temperature that can kill humans is probably going to destroy your PLA prints so a cell phone holder for a car? Go for ABS, not PLA. Also note that ABS clogs nozzles easily when baked. So while you can print super hot with PLA (say 240C) without any nightmare problems, if you print ABS at say 260C and things seem fine but then you pause the print for 2 mintues (at 260C) and then try to resume you will probably now have a permanent clog in the nozzle that needs soaking in acetone or burning out or careful toothpick digging while hot.