some layers not printed correct in simple ABS cube

[barryschulte]

Hi everyone,

i’am trying to print a simple cube shaped object with walls of 2.5mm thick. But somehow every print i’ve tried ends up with a couple of layers that are not well connecting. See picture…

i’ve tried low/medium/high res with low/medium/high infill, but all of them have similar issues.

to me it seems that the possible reason might have something to do with the slicer becaus the the inner and outer shell are not connecting even with infill at 100%.

printer: wanhao duplicator 4 with ABS filament

slicer: both makerware and simplify3D

anyone a suggestion i didn’t think off??

Greetz Barry

[MB3D]

Hi Barry,

since you use ABS as material this can be due to warping. If you have a heated bed, but not a heated buildchamber only the lower part of the ABS print gets properly heated. Another cause could be vibrations or other issues with the steppermotors, but it doesn’t seem like that.

Did you experience this problem with other materials / models ? Try printing the cube in PLA to get a good comparison. To fix the warping issue with ABS prints you should experiment a little bit. I got splitting layers for thi prints, thicker shells worked better most of the time, also you might want to print with a cooler hotend, but slower and you have to shut down every fan !

Lower layerheights with a wide nozzle (if you can change that) might help, but there’s no 100% solution since every printer, material and printing environment is different. A last tip might be to increase flowrate (at least in Simplify3d) so that more material gets better layer-to-layer bonding.

Let me know if anything of that helped, to test if thin ABS prints are a big problem for your printer just try to print a 5cm diameter cylinder that has just one or two outlines and is fairly high, you should see splitting layers after some centimeters of height.

Good luck printing,

Marius

[Alex3DHubs]

What were the print settings that you were using initially?

[barryschulte]

Thanks Marius,

Allthough I am not sure I don’t think it is a heating problem. The cylinder is a good idea, I will folow op on that. And I am gonna thicken the shell a little… running out of time for the customer…

thanks Barry

[barryschulte]

I’ve tried many so far…

but I started with 0.15mm, 4 shells, 50%infill, 230C, no support, no raft (buttom layer needs to be smooth). I’ve noticed that the infill doesn’t effect the print at all. The inner and outer shell are not connected whether I try 10% or 100% infill…

The only thing that puzzles me is that is only effects some layers and not all amd come to think of it… it are the same layers every time…But there doesn’t seem to be a trigger in the design that starts it (could be resonating)

I am now printing a similar design with differtent fillament…see how that goes…

Barry

[barryschulte]

update!

with my different (but similar) obect and different ABS I got the same after a couple off layers…

[steven_10]

if you print more than one cube, does it effect the same layer every time?? if so have you recently cleaned off your ‘Z’ Axis lead screw? scrap bit of filament stuck in the thread can sometimes cause this.

If not is it under extrustion? Start at the spool, how difficult is it to pull the filament to the extruder? as an example I have both my spool holder and filament guides running on bearings. next check the hobbed bolt is it clogged? whats the tension like, next check that the filament can be smoothly pushed through the Bowden (if you have one) and into the Thermal insulator (if yours is PTFE check for wear on the inside diameter).

Hope this helps.

[DeGrazendeSlak]

Je zou het stl. model kunnen checken op kwaliteit met meshmixer.

[CrispinPrinter]

I had something similar with a cheaper filament I bought - they had wrapped it so tight on the spool that the inner layers were jammed / much stiffer to unreel.

[barryschulte]

Thanks Steven, but that seems ok with my printer. And yes, it’s the same layer everytime…and there are also no problems with the filament…

this morning someone told it might be a temperature drop of the extruder. i’m gonna look into that to.

cheers!

[CrispinPrinter]

If you play it back S3D does it do it there? Perhaps you have some open parts? (i.e. not water tight)

[ScottObjectForm]

Hey Barry, we use the same brand printers and have experienced this before. Usually it is poor material or the simplify3D settings are not what they should be for the material being used.

If you have no objections send the STL file over to me and I will give it a print with our equipment (same set up). If I get the issues we know it is object design, perhaps the object is not closed correctly or you have some hidden geometry that has not been fully removed or compensated for.

scott.Knowles@objectform.co.uk

Scott - Director at ObjectForm.co.uk

[barryschulte]

Hi Scott,

it seems you might be right on the poor material… I’ve tried a differtent ABS and is much better already. Now i am trying one with higher temp (260) and I think I should be OK. I’ve asked a fellow Hub in the neighborhood to give it try last night and that was ok to, so it can’t be the design. Tried several slicers (simplify/makerware/sli3er/ and that made no difference…

thanks for the offer…

Barry

[steven_10]

Hi Barry,

You say that the new material is much better, but does this mean you are still seeing something at that point on the print?

If this is so i am not convinced its the material yet, if this were the case it would occur randomly though out the print! the fact that it repeats on the same layer every time indicates something either in the sliced G Code, or something more mechanical…does it run linear bearings on the ‘Z’ Axis? does the pitch of the missed layer match one complete revolution of the bearing internals?? so you have a stick slip scenario.

I hate problems like this! they are always something silly and simple when you do finally resolve them!..lol

[barryschulte]

Hey Slak

gecontroleerd, geen fouten gevonden…

groet Barry

[barryschulte]

you are so right… only the customer gets a little nervous because of her deadline and if they get nervous… well…

different ABS and 260C is definetly much better… But I do still see some thin lines on different heights though…

still a little mistery too me but at least I have something for the customer…

[amathey86]

Hi Barry!

Did you solve your problem??
I have kind of the same problem! I’m trying to print with white ABS a kind of box quite thin (see pic). Always between 10 and 15 mm high is a layer not properly connected. At the beginning, i get a little slot which is getting bigger and bigger after each layer. After smtg like 50 mm high printed, we can praticaly see through the slot. I’ve been printing a lot with ABS till i found the right parameters. I printed a lot of differents pieces and it’s always ok.

With this last piece i get always this problem… i changed the parameters, but it’s always the same. I do not have warping at all on the buildplate, the piece stay really well on it. what i think is that the stress due to warping and temperature changed which is not occuring on the buildplate (due to the hairspay) might be occuring higher… I put on big carton (a box )on the printer to keep as good as possible the temperature.
Smtg is at the moment printing. But it could be as one of you said the z axis at one point not clean I’ll check that and let you know if it’s getting better.

Otherwise, What do you think about my problem ??

Thank you!