Not solid top layer

[matis 0]

Hi,

few days ago I finally finished building my Ultimaker Original and started printing:)

I started to print little blocks just to try settings,... My problem is that top layer of blocks is not solid, there are little holes. No matter the setting I tried, holes are there:) Iam starting to think that is problem with Z axis because my first layers(bottom ones) are nice and solid but top ones are not. Any advices?

Iam printing with PLA recieved with my Ultimaker and print settings are:

 

• layer height: 0.2
  
• shell: 0.8
  
• retraction: on
  
• bottom/top: 0.8 I also tried 1.2
  
• speed: 80
  
• temperature: 230 I also tried temperatures from 190 to 240
  

 

Thanks for the advices and excuse my poor English.

 

 

[martin-bienz 36]

Hi matis, welcome to the UM Community! Are you using Cura to slice? Which Version? Are you printing with 100% flow rate? Diameter Setting (2.85)?

I think you should start printing at a lower temperature. start with 210. I print UM filament between 200 and 210. Also, is your temperature reading steady or does it jump up and down a lot (jumps of 10C +)?

Have you calibrated your Printer? Meaning the axis aligment, steps etc.? Check http://wiki.ultimaker.com/Calibrate

Also and in this case, have you checked the E-Step settings (the amount of filament that is extruded). You should follow this procedure:

http://voltivo.com/blog/ultimaker-3d-printer-calibration

After you have adjusted your e-step (x,y,z also) settings, press store in Memory, so it gets save. I would also suggest to write the settings down (just in case you need to reset your settings).

 

[matis 0]

Hi, thanks:)

Iam using latest Cura, 100% flow and 2.9 diameter setting which is my average diameter when Iam measuring it. As I wrote above, I tried temperatures from 190C to 240C and result was the same. Temperature is pretty much steady sometime it is -+ 5C.

 

Printer is calibrated except E-Stem. I will try that.

 

[gr5 2,230]

 

• bottom/top: 0.8 I also tried 1.2

 

1.2 is smart to try. Gives it more layers to recover.

 

temperature: 230 I also tried temperatures from 190 to 240

 

240 would help the plastic flow - also smart.

I see two problems in the image - one is very clear and obvious to me. You have a loose belt or belts. Probably the short belts (slide the motor down harder). When you have loose belts you see diagonal passes on the top - you see 2 passes close together and then a gap. Here is more discussion on this - read post #7 and #8:

http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/?p=14396

Also you may have some underextrusion after you fix the backlash. Underextrusion can be fixed by printing slower or at higher temperature. Fix the backlash first.

 

[matis 0]

ok, so I did e-step calibration and adjusted short/long belts and it is much better still not perfect but,...

Thanks a lot.

 

[martin-bienz 36]

matis, glad it's better. could you still post how much e-step you had to adjust? Did the belts, as suggested by gr5 where to loose? It's also for us to be a able to tell what the problem really was.

updated pictures please if you say not perfect... um1's are rather perfect :mrgreen: normaly.

 

[matis 0]

I was out of town, sorry :/

I dont remember exact e-step value but extruded filament was about 2mm shorter. I also adjusted one short and two long belts because they was loose. Top layer is still not solid but gaps are closer together. I will probably try adjust belts more.

I still dont understand why are botton layers solid but not the top ones:)

 

 

EDIT: I printed belt tensioners for all long belts

 

 

[martin-bienz 36]

hmmm... still underextruding. can you move the printhead by hand with no problem (should be rather easy)? Also, can you insert and extrude the filament without problems (no hickup, no friction should be smooth). Can you extrude without issues by hand if it's hot, by turingin the gear (are you printing at 210?)

Change filament.

I am just guessing at the moment.

 

[matis 0]

no problem with moving printhead by hand, filament goes inside smoothly and I can extrude just by turning the gear. Currently printing on 240 as gr5 suggested, it seems I have best results with this temperature. Anyway in a few days I will replace some parts on printer, then I will update.

Thanks a lot.

 

[antiklesys 3]

HI Matis, check bed levelling and distance between the nozzle and the printing plane.

If the nozzle is not touching it, lines might become like that.

 

[matis 0]

@Antiklesys

nozzle is about one paper height from printing plate - it should be ok. thanks

 

[martin-bienz 36]

I am right you are printing at 240? That's to hot for PLA if all is right and the speed is not to fast. Do you have the possibility to check the real temp of the nozzle (with an external thermo)?

Can you try at 200 (check your filament please) with 50 mm/s and 0.1 layer height, that's what I use every day.

Also, important, which version of Cura are you using!? Can you try with an older version then 14.03? (14.01 OR 13.x) Just to be sure...

 

[polygonprods 0]

Has anyone actually solved this issue? I've read three threads now with no real mention that it was solved or not.

 

[matis 0]

I did not solve this, it is better now (dont know why) but far from perfection :(

 

[deepshots 2]

I've had this same issue for ages. My trick is to really slow down to crawling speeds for the final 2 layers and rise temperature a bit plus turn the three screws leveling screws so that the final layers really squeeze on the print. (sometimes I just lift the build plate by hand and keep it there for the final layer)

Not ideal but that's the only way I've managed to solve this.

I should say that the gaps seem to be worse when on 0.2mm