Need advice for 3d printed ABS parts.

[Saikedo]

Hi, I am attempting a Voron 2.4 build and I am having some issues when it comes to printing the ABS parts. Hoping someone will have some advice for me so I can improve the printed parts quality.
Now I know that this is not ideal because a lot of things depend on filament use, the 3d printer used for printing, and of course slicer settings but I will do my best to provide information about all of these without being overly overwhelming.

I am mainly facing 3 issues when attempting to print these parts with ABS, never printed with ABS before but I never faced similar issues with any other plastic type that I tried before.
Please see attached image demonstrating all 3 of these issues.

1. Small holes throughout the surface, seems like plastic is just missing for that specific 1-2 mm
2. layer lines just look terrible when viewing the parts from above, they look relatively great from any other angle.
3. Shrinking/warping. Is this amount of shrinking still fine or this won't work? All other parts that I printed so far are much better, but this part specifically is shrinking at the bottom no matter what I tried so far.

I am printing these with a Qidi X-CF Pro, enclosed printer, 110C bed temp, 230C nozzle temp, and ambient temperature inside the printer is somewhere between 60-70C. I tried printing these both at normal speed (which is not that fast at around 60mm/s) and also slowed down and the results were pretty much the same.

Thank you.

 

[LoadMaster7]

This is all tuning of printer and slicer program. This Tuning Guide can work with pretty much any printer. I would suggest looking through it for your issues. The
Troubleshooting guide gives examples to match your photos to, and what the issues is.

Welcome!

Ellis’ Print Tuning Guide

ellis3dp.com

 

[msaeger]

Are the little spots in the first photo maybe the start or end of a layer? I have always had abs nozzle temp higher than 230. The stuff I have now I am using 255. For warping what is the bed surface?

 

[Saikedo]

Are the little spots in the first photo maybe the start or end of a layer? I have always had abs nozzle temp higher than 230. The stuff I have now I am using 255. For warping what is the bed surface?

The dots are not the z seams, that was the first thing I checked. Z seam is on the opposite side of those dots.
As for the bed. Tried every type of bed there is Actually the bed adhesion is perfect now, no part of the print gets curled away from bed but the bottom part still warps while bed adhesion is intact

 

[NoGuru]

Dots look like water in the filament. Dry it.
Have you done any tuning with the filament? Looks likes temps fan speed and print speed are off, which is why you have that strange looking shrink or wabble in the print. Don't worry about layer lines from above, all prints from all printers will look like that if you take pictures in certain light at that angle.

 

[Saikedo]

@NoGuru The filament as dry as it can be. Dried for like 24 hours and it is still sitting in filament dryer while printing. Part cooling is turned off (I also tried with 20% fan speed and got the same result). As for speeds, I am printing slower than my regular speeds hoping that it will turn out better. You think slower speed can cause such issues ?

 

[msaeger]

Is it pulling up the bed then or something? I mean if it's still attached to the bed how can it not be flat?

 

[Saikedo]

Its not pulling off the bed at all actually. The bottom of the print is perfectly flat (at least in my latest attempts). Its just couple of layers above the first one it shrinks and then halfway through the print it kinda stabilizes.

 

[NoGuru]

Try using a different slicer to see if it makes any difference.

 

[Saikedo]

To anyone who will stumble upon this post with similar issues.

It turned out that my major issue here was the bed temperature. Everyone keeps saying that we need high bed temps for ABS printing, well it turned out that there can be too much of good stuff I was running my bed at 110C and also using a heated chamber and I was getting terrible warping issues. I lowered the bed temp to 95c and also started using Magigoo MO2016 for better adhesion and I even stopped using the chamber heating and the prints come out beautiful now, 0 warping. Ambient temperature inside the enclosure(closer to the print surface) is on average at 53c.
The horizontal lines that I was seeing turned out to be there for all materials, it`s just the specific ABS I was using was making them look much worse. I switched to Paramount 3D abs and things look much better now.

Take a look at the new results that I am getting now in the image below (Note, you might notice that I got a tiny bit of elephants foot going on on the bottom layers but that is because I run the nozzle a bit closer than it should be on purpose to get that nice uniform textured look on first layers. With this approach first layers look just fantastic, does not even look like 3d printed parts).

 

[NoGuru]

Glad you got that sorted out.
What is the recommended temp for the bed from the manufacturer? It's different from each brand.

 

[Saikedo]

Glad you got that sorted out.
What is the recommended temp for the bed from the manufacturer? It's different from each brand.

I was using hatchbox ABS before, there was no recommendation for bed temp for that. I switched to Paramount 3D now (it`s a bit less shiny, which I like) and Paramount 3D is recommending 100-110 for the bed but I still run it at 95 and had 0 issues with sticking/warping.
I also use Qidi X-CF Pro 3d printer for printing these and the QIDI slicer defaults to 110c bed temp for ABS profile so I was not even suspecting that bed temp is the culprit here. Maybe if I could bring up the ambient temperature somewhere near 85-90c it would have worked fine with such high bed temps but I don`t see a point in doing that at least for Voron parts. Prints just fine without active chamber heating.

 

[evo_grind]

seems odd too hot bed would cause such inconsistent contraction... did you do PID tuning?

 

[majic79]

How big is the chamber on the Qidi? I've no idea and haven't googled it yet - but I'm wondering if the chamber is still too cool for it to be effective? Perhaps it's cool during that part and by the time it's returned to normal printing, the chamber is warmed? I saw similar effects printing parts with a cardboard enclosure on my other printer, had to make sure the chamber was well saturated before I started to get a good print out of it. I use 110c bed temperature now and 50c chamber temps and I don't start printing until my chamber is at least 40c

Edit to add: I'm using Hatchbox also and have to take nozzle temperature to 250 to get it to flow properly

 

[igiannakas]

The dots are retraction related. You’re retracting too much and bringing air in the nozzle. Had that happen to me- reduced retraction to 0.6mm and it was gone. Your filament doesn’t look wet else you’d be having more surface issues.

 

[Sandman50]

I need bed fans to get to 50c in a 2.4 350. Going to add in a chamber heater to get it to 50c when the garage is cold in the winter. I use the exhaust fan set with watermark to regulate that temperature. 50c seams to be perfect for ABS.