Please help me diagnose this issue

[tsteever]

I have some weird artifacts in my prints. I know I need to recalibrate as it appears I am over extruding. I had my PLA prints looking great. ABS, they look terrible.

Take a look at these. I think the top layer could be fixed by running the extruder a bit slower. What I am wondering about is what causes the external perimeters to mess up like I have attempted to picture here.
IMG_3096 2.jpgIMG_3095 2.jpgIMG_3082.jpg

[mattanonymous]

I'm no pro, but the black looks like the hotend temp is too high.

I'm getting the same artifacts on some black PLA that you have in your red filament photos. I'd love to know what the cause is! Maybe it's the filament?

[lakester]

Is there any warping during the print sufficient to disturb Z positioning significantly? I.e., is your hot end gouging into the part ever? While it looks like that probably isn't the case, just thought I'd mention it...

FWIW..., even though a part can be adhered to the table really well, it can still warp, but remain sufficiently attached to the table such that the HE will just keep ploughing through the part w/o the part coming unstuck. Kinda shocking when you first catch it happening...

[voodoo28]

+1 on too high on the temps..

[tsteever]

Thanks For the tips! I will try and lower the temps, I am already at the low end of the suggested range. This was printed at 220 which is the lower limit on the ABS.

My suspicion is I may be over extruding a bit. On the small parts there isn't room for the material to go anywhere but out. There are times when I have noticed the nozzle drawing through the print a bit and bouncing over the already cooled plastic. I am not sure about that situation. Skipping steps? Would that cause this? Again, I suspect over extrusion.

[tsteever]

I recalibrate things a bit better and I am happier with the results. I lowered the temp to 210 and then down to 205 but I think I went too far as the layer started to separate just a bit.

[Roxy]

Thanks For the tips! I will try and lower the temps, I am already at the low end of the suggested range. This was printed at 220 which is the lower limit on the ABS.

Do you know that your printer's temperature is calibrated? Is it possible that it is off by 5 or 10 degrees?

[tsteever]

I really don't know about the hot end calibration. I have done the PID tuning. How do you calibrate the hot end?