Problem with a Ultimaker 2 bed (uneven? Warped?)

[devilflash 2]

Hello everyone and merry Christmas!

 

I come to you for a problem who took me by surprise without any announcement. Some parts of the bed seem too high and others too low.

I try to print something and the first pass of the rim goes well, it seems the filament sticks well on the buildplate (I tried with bare glass, buildtak, the glass turned upside down, with flexplate) but on the second pass the filament doesn't stick anymore in the back of the surface as you can see on the picture.

I hear some grinding noise from the extruder (a bondtech...I cleaned the gears to see if THAT was the problem, didn't solve anything and it has plenty grip power)...

I really don't know where it can come from. Yesterday, I changed my heatblock for a 3D Solex matchless with adapted nozzle, a brand new steel hot end isolator and brand new TF2K300C coupler. I checked the heat cartridge, the sensor (maybe the filament was too cold to glue)...they look well attached, they didn't move.

I try to correct the bed height on the fly with the 3 screws...doesn't help much.

Damn, I've my printer for 3 years now and I start to have more and more problem with it. I succeeded hundreds of hours of printing on a Mark46 Iron Man armor the past month and for the last 3 weeks I've problems on problems...my nerves are more tense than a convoy belt!

Any helps are welcome!

 

Antoine

Edited December 23, 2017 by devilflash

[yellowshark 153]

Hi, it would be helpful if you could give us your major settings to help, this happens a lot on these type of problems, if we do not know the settings we have to make assumptions and end up guessing what it might be rather than giving you a probable answer. At least speeds/ layer heights/bed and extruder temps.

 

 

1. Is that a brim that has printed? If you do not have a brim set then for something that size I would recommend a brim  - nothing to do with your problem, just a hint.

2. It looks as if the bed is sloping down from front to rear.

3. Also do not forget that when you changed your nozzle you may have changed the nozzle to bed distance, which would probably contribute significantly to the problem you are seeing, level bed or not level bed.

4. Are you using an adhesive on the bed. If you are is it evenly applied across the bed? No to either of those questions will not help you.

 

5. Ok, get yourself relaxed and start again from scratch. Go through your bed levelling procedure, slowly and carefully.  When you think it is right, check it carefully, at least twice.

6. If you think it needs to be tweaked then repeat 5.

7. Go through your nozzle to bed distance process. I appreciate you may combine this with 5, which is OK but I do not do it that way. Again slowly and carefully. Again check and check, it should be the same  left and right and front and back on the bed. A variation of 20 microns, or an error in your target distance of 20 microns may well show a poor result. An error of 40 microns will show a poor result.

8. There are some experienced users on here who adjust the nozzle to bed distance on the fly and it clearly works for them. I have done that on a few occasions but I do not normally do it that way. I do not consider myself to be able to get to 20 micron consistency and accuracy using my fingers and thumbs – sure I can get a working result but not an optimum result.

 

And we all have bad days. I consider myself to be pretty experienced on this subject but earlier this year I could just not get it right – I spent hours on it and needless to say the longer I spent the worse it seemed to get. That has only happened to me once in 4 years but the point is it can happen, which is why  I am suggesting to you to relax and go back to the beginning.

 

Of course it might be something else totally different

 

You will get there.

 

 

[devilflash 2]

Print temperature: 210°
Filament: PLA
Layer height: 0.2mm

Speed: 80mm/sec

Bed Temperature: 60°

1. Yep, it's a brim. For this kind of object (raspberry case, so, large but not high), I usually don't use a brim but in this case, yep, it's a brim.

2. It looks like it yeah...but that doesn't explain why the first passage looks fine and it starts to make a mess after nor the grinding noise from the extruder. Also, it's well leveled prior the printing.

3. Not sure what your mean with nozzle to bed distance but I went through a large amount of bed leveling cycle with the paper to get the 0.1mm distance just right.

4. I tested with the glass only, with an adhesive print surface evenly applied (buildtak).

5. I checked most of the part of my printer. I checked the frame, looks fine, I checked the heat block with the cartridge and the sensor, they look fine, the axes look fine, I put a ruler on the glass, doesn't look concave or convex... I should check with a spirit level. That's the last thing I can think of. I did the bed calibration tens of times with nozzle to bed distance in the same process as many times as the bed leveling process.


6. see 5.

7. see 5.

8. I even tried that after a nozzle to bed distance done during bed leveling phase. When I make a bed leveling/nozzle to bed calibration, I always check the first layer to see if it needs some tweaking on the fly.


Thank you for taking the time to answer!

 

I wish you all a merry christmas eve

 

Antoine
 

Edited December 24, 2017 by devilflash

[yellowshark 153]

  OH thanks for that, some more questions/points.

1. Print speed is 80mm/s. What is important is the print speed for the 1^st layer, which I assume is not 80 mm/s. If it is 80 mm/s, I respectfully suggest that is too fast, reduce it to 20mm/s.

2. Sticking with that point, and nothing to do with the 1^st layer  but I suspect that if you are trying to print .2 layers at 80mm/s the 210 extruder temp may not be hot enough. All printers are different, as are all filaments, so it is impossible to be prescriptive but if it were me (and I never print that fast) I would be inclined to start at 215-220 and then if relevant reduce the temp. until it is right

3. Set you first layer to .3 layer height – the thinner the 1st layer height the more difficult it is to get adhesion unless your bed is absolutely level and nozzle/bed distance spot on

4. A 1^st layer of .3 at 20mm/s, for adhesion purposes, should be OK at 210; I would probably go a bit cooler but 210 will be fine I am sure.

5. If you have one try a different PLA filament; this may not do anything but it will knock out one of the variables – and often using a different filament can resolve an issue, at least temporarily.

6. The nozzle to bed distance IS the .1mm you are aiming for. Bear in mind that sheets of A4 paper are not all the same dimension; some are .15mm.

7. You say you hear your extruder grinding. Is that with all passes or does it start with the 2^nd pass? Is it all the way around or is it just in certain positions on the circumference?

8. How many passes were made before you stopped and took the photograph?

9. Oh yes, push your 1st layer bed temp to 65; nothing wrong with 60 but you have a problem and a warmer bed temp may help.

If all the above fails I have another suggestion.

[yellowshark 153]

  OH thanks for that, some more questions/points.

1. Print speed is 80mm/s. What is important is the print speed for the 1^st layer, which I assume is not 80 mm/s. If it is 80 mm/s, I respectfully suggest that is too fast, reduce it to 20mm/s.

2. Sticking with that point, and nothing to do with the 1^st layer  but I suspect that if you are trying to print .2 layers at 80mm/s the 210 extruder temp may not be hot enough. All printers are different, as are all filaments, so it is impossible to be prescriptive but if it were me (and I never print that fast) I would be inclined to start at 215-220 and then if relevant reduce the temp. until it is right

3. Set you first layer to .3 layer height – the thinner the 1st layer height the more difficult it is to get adhesion unless your bed is absolutely level and nozzle/bed distance spot on

4. A 1^st layer of .3 at 20mm/s, for adhesion purposes, should be OK at 210; I would probably go a bit cooler but 210 will be fine I am sure.

5. If you have one try a different PLA filament; this may not do anything but it will knock out one of the variables – and often using a different filament can resolve an issue, at least temporarily.

6. The nozzle to bed distance IS the .1mm you are aiming for. Bear in mind that sheets of A4 paper are not all the same dimension; some are .15mm.

7. You say you hear your extruder grinding. Is that with all passes or does it start with the 2^nd pass? Is it all the way around or is it just in certain positions on the circumference?

8. How many passes were made before you stopped and took the photograph?

9. Oh yes, push your 1st layer bed temp to 65; nothing wrong with 60 but you have a problem and a warmer bed temp may help.

If all the above fails I have another suggestion.

[devilflash 2]

1. When I check in Cura the top/bottom speed, it's 15mm/s. But it wasn't ticked before I check. I imagine it's still the speed used for first layers.

 

What is strange is that I never changed anything in the settings. I've printed hundreds and hundreds of hours without having any issue with the adhesion. In fact, I use Cura with default setting except for layer height, adding support or brim, and rarely printing speed. Don't know why that happens now.

 

The thing is, two weeks ago I had some issue with bad under extrusion, so I checked the heat block, PTFE coupler and so on. I planned to change the coupler and some part so I bought an Olsson Block V3, matchless nozzle (that can print faster with same temperature or with a cooler temperature at the same speed). I changed some time ago the heat cartridge from the 25W stock  to a 35W.

3. I will try a .3 layer height and give some feedback.

5. I will try it with a brand new filament spool.

7. It starts at the second pass. I can't remember precisely where but I think almost everywhere. I'll check that though.

 

8. I stopped after maybe 5-6 passes

9. will do

 

Thanks!

[rebekah_harper 60]

hiya,

 

there is a bad batch out there.  This was my original bed. I got a new from the uk importer and it was the same. so I went there and we got a brand new one from their stock and it was the same too.  so we took one from a different stock batch (difference was black corner protectors instead of white ones) and it was as close to flat as you could get it. 

 

so nothing you do will make a difference in this case.

 

however I have still one corner on my UM2+ that causes an issue which I solved with some paper underneath.  It's the heated bed that's on the piss though not the glass. 

 

but there is nothing you can really do with a deviation of 0.6mm.  you can check this by raising the bed to 0 and by hand move the head around the bed.  as you do this be at eye level with the bed and you can see where the height issues are.

 

with the condition below it's a manufacturing fault so you should be able to get a replacement. 

 

[devilflash 2]

Yeah but why now? After 3 years of good services? That's weird.

[rebekah_harper 60]

for me I wasn't printing large parts 1/4 of the build plate and was adjusting the bed during the start of the print. but when I wanted to print using 3/4 of the bed it became parent that this was an issue.  and eventually the cause became know.

 

if you have been printing perfectly up until now. 

 

level the bed as per normal. then raise the be to 0 and manually move the head around and see where the level issues are.  if they are in one corner use some paper to raise that corner to the right level.  relevel the bed as per normal and check.  I did this a couple of times.

 

it takes some heat to warp the bed so I can't imagine it being the case.