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arjen

PLA not sticking to the bed and warping

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Hello, I received my Ultimaker 2 a few weeks ago and made some great smaller prints so far, but recently I'm working on a slightly bigger print but found that the material won't stick enough and is warping quite a bit at times.

 

I releveled the bed countless times, printed with bed temperatures from 60 to 75 and in between. Used several different rolls of PLA material, it's a correct 2.85/2.90mm. Also printing with speed 50, this helped a lot but not far enough yet. Also fiddled with the material flow a little and the print temperature as people on this forum mentioned but no success.

 

I tried a clean glass bed, tried using hairspray (super hold/strong) and glue but nothing seems to help. Maybe I'll have to try the ABS acetone mixture if that works properly with PLA... rather be hammering a print off the build plate than have it pop off half way by this point.

 

The problem is the print just pops off the bed after printing due to the warping, making supports just fall off half way and sometimes the print head will start ramming itself into the print due to the warping.

Hope anyone can help me, I'm out of idea's.

 

Here are some pictures of the problem.

IMG 3911

IMG 3912

IMG 3913

IMG 3914

IMG 3915

IMG 3916

IMG 3917

IMG 3918

IMG 3919

 

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Hi Arjen

Welcome to the UM forum.

 

This picture shows your problem.

As one is looking onto the first layer on this picture, one can see that the lines of the first layer are not closely together and rather round than of rectangular shape. The first layer should be one smooth surface with no gaps between the lines. If you run your finger nail above the surface you should hardly be able feel the lines.

So, what to do. Check (again?) the distance between nozzle and bed surface. It should be equal to the thickness of a sheet of paper (80g/m^2).

Didier Klein ask an important question. If you have 0.1mm as first layer height, try 0.2mm. This might level out some problems with a non-ideal leveling. If you have 0.3mm, also try 0.2mm; this reduces the flow which is not a bad idea with an UM2.

Other reasons could be that the filament flow is lower than it should be. You already measured the thickness of the filament. If you haven't done this about ten times at different spots, please do it. Take the smallest diameter you measure for the setting on your UM2 (you risk some overextrusion, but that's easy to correct).

What temperature are you printing the first layer? Try going higher in 5 or 10 degree steps but don't go over 250°C. A higher temperature makes it easier for the feeder motor to push the filament.

What speed are you printing the first layer with? Don't go over 20 to 25mm/s for the first layer for the moment.

I hope one of these measures solves the adhesion problem. If not, please come back, you will get a lot of other ideas from the community! :)

edit: It's a good idea to watch the printer doing the first layer right. Without a good first layer chances on a good print are minimal...

Here is an example of how the lines on the first layer should look (it's actually a brim, but this doesn't matter):

Example for a 10-lines-brim

 

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Thanks for the replies! I'll try a run with Brim and hope it won't warp...

 

This picture shows your problem.

As one is looking onto the first layer on this picture, one can see that the lines of the first layer are not closely together and rather round than of rectangular shape. The first layer should be one smooth surface with no gaps between the lines. If you run your finger nail above the surface you should hardly be able feel the lines.

 

IMG 3912

This one shows a more flat surface, I had a variety of different surfaces from even smoother than this one to more gabs.

I'll try setting the temperatures higher in 5 degree steps and fiddle more more with layer height and let you know how it goes. :)

 

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I hope this fixes your problem. 215 is a bit cold for first layer. I recommend 230 or 240C (no hotter than 240C) for the first layer if you want it to stick better then lower to 215 (or whatever) for the remaining layers. Bed needs to be at least 50C.

This part should be easy. For really large parts - over 100mm you might need more extreme measures. For example having the bed at 75C (but 70C might be enough) will keep the bottom layers above glass temp so that they are still very soft and so it can't warp - but it is easy to wreck the part when it is that warm - but usually it's fine. Defintely don't try to remove the part while it is still above the glass temp.

Please don't post links to dropbox unless you plan to keep that account and those pics up for 100 years. Someone might come back to this forum looking at your issues and if you del the pics off dropbox next week it will - well suck for them.

In the future go to the "gallery" link in the top left of this page, click the big blue "upload" button. AFter that is done start a new posting and click "my media" next to the smile face.

 

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Thank you for the tips, so far it seems the layer is holding perfectly thanks to the new settings. I'll try to use 230 or 240C in future prints.

I have updated the images, sorry about that, not used to making a separate gallery outside of the posting of a topic. But I understand why you'd like to keep links working for future references.

I'll post more once the print is done or failed once again.

IMG 3924[1]

 

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Was printing on 0.3mm first layer, printing on 0.2 now, set nozzle to 215 and using brim, see the images below. Let me know if this might work or not? So far no warping but might happen in the next few layers.

The first layer looks much better know. Actually, you have a slight overextrusion now, as I predicted it before. It's nothing you really have to worry about unless the nozzle rumbles well audibly across a previous layer.

You may try to find optimum settings for which the PLA is not pushed up outside the nozzle tip. But don't do this during a 'real' print... ;)

I hope, you will soon hold your first successful large print in your hands...

 

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You may try to find optimum settings for which the PLA is not pushed up outside the nozzle tip.

 

Yes I noticed some PLA sticking on the tip from the very beginning, wiped that off as i paused for the photo. So far it hasn't rumbled, but what would be the best thing to do if it did start to do so over previous layers mid print?

 

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The most important thing: DON'T PANIC! :mrgreen:

It's quite unlikely it starts really mid print as long as you don't change anything on the print settings. If you really see the tip of the nozzle colliding with e.g. warped printed parts you can reduce the print speed directly in the LCD menu until things level out.

There are two things you can do in general if you see that too much filament is printed. You can carefully reduce the temperature a bit (maximum 5 degree) OR equally careful reduce the flow directly on the printer. After a change wait some time (e.g. 20s) until the material flow is in a new balance. This is also something you may try with a smaller print first. Important is that you give the printer some time to react on your changes. Reaction does not occur immediately.

 

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Finally worked, no warping at all, it printed perfectly! I reduced the speed to 40% during the night to make sure it would print properly, build plate temp was 75c after slowly upping the heat slightly over time from 70c. Nozzle heat was 210 in the last half of the print, also slow reduction, it overshoots quite a bit.

 

I'll keep experimenting more with the tips I got.

 

Thanks everyone for your help!

IMG 3925

 

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This is a helpful thread for those of us trying to find answers to common printing problems. Is there a place in Cura to set the temp for the first layer? I have looked and cant see where I can set that up. Perhaps I tune it just before it prints then lower the temp once the first layer has printed?

Thanks,

 

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Is that the bottom? if so you have a serious leveling issue - you need the nozzle A LOT closer to the glass. Maybe .1mm. Maybe .2mm. That's a lot. What printer do you have? UMO or UM2? Either way you turn the levelling screws. I usually do it while it prints the first layer but you can turn probably 3/4 of a turn on all your bed screws - then print again. While printing bottom layer only adjust 1/4 turn at a time.

I do *not* recommend running the leveling procedure. You are close enough that you can do it on the fly while printing the brim.

 

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For the love of God, i need help. :angry:

Im a beginner but for a while now im regularly printing objects. Out of nowhere, when i was printing an object that I've already printed before my printer got crazy and the material wasn't sticking to the bed plate AT ALL, not even the first layer, the material just made a huge ball of nothing on the outside of the nozzle.

Since then i made factory reset, changed the material and releveled the bed plate several times but nothing worked, below are some photos and a video of me trying to print the double hearts voroni that already comes with the printer.

Video of The Problem

open?id=0ByDRnT3SwdVsaVhXMDBqdWVZVm8

open?id=0ByDRnT3SwdVsdkdrcTZxNVBDLVE

Please help me, i don't know what to do, and i was about to print somethings to give to some people as a gift. :(

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