Hi,
I’m trying to print a part in lulzbot taz 6, but the layers don’t seem to be coming out right, on one side the layers come out perfectly, but on the other side there is this. I was wondering if anyone here could enlighten me on how to fix this, or what might be causing the issue in the first place. I doubt that it has anything to do with the room temperature, as the temp is around 31 degrees celsius. The object was positioned with the good side facing towards you and the bad side facing away from you, every time the side that did not have a smooth layer was the side that was facing away from you. The material that I’m using is ABS, the printing temperature is 240, and the bed temperature is 111. The bed temperature is 111 to compensate for the approximate 1 degree loss in temperature when the bed moves. This is the entire part and how it was positioned on the bed.
Side 1
Side 2
Side 3
Side 4
Thanks!
I’ve seen this before on my Taz 5, but only using Symplify3D software. Symplify3D has many available parameters to control and can be overwhelming until you get to where you understand it better. It is a cooling issue during those layers. Make sure the fans are not running and adjust your outer perimeter wall speed and or thickness. The layers are cooling too fast in that area. Also, check your extrusion flow rate. Do only one parameter change at a time so as to isolate the issue.
Well I’m not using Simplify3D, I’m using cura with the default taz6 profile with high quality. I dod try printing it once without the cooling fan turned on, but the entire part came out as a molten blob. The extrusion flow rate is 100%; would you recommend I change that? if so, then by how much.
Just a random question: does that have anything to do with the infill, as the infill is 80%, and yes i need the part to be relatively strong.
Cura handles the fan differently then Simplify3D. Yes, leave the fan alone in Cura. The infill has a lot to do with it. It certainly affects the way the part cools as its printing. I had forgot about asking you what the infill setting was. Reduce it by 10% or more and try another print. Your part will be very strong even with reduced infill. Its the areas that need a screw, snap connections, or support pressure, that need to ensure strength. What I do is design my parts so they are stronger in those areas. Also I adjust perimeter thickness where needed. For example, a screw hole may need a thicker wall, so I set the wall parameter to 2mm or 3.
Don’t change the extrusion flow. That should be a good setting for ABS in Cura.
I have another question: Does it have anything to do with the filament being fed into the extruder with a bowden tube.
Here is the link to Symplify3D’s quality guide that helped me a lot. Print Quality Guide | Simplify3D Software
It doesn’t have your current problem spelled out per say, but helps define what affects each parameter has on the print.
Well thats a bigger discussion. With so many different brands of filament requiring different temperatures, the flow rate, friction in the tube all are affected. Unfortunately, its an experimental journey. Once you have a good setting for a brand of filament save it and keep using that brand. You’ll find even different colors of the same material and brand have to be adjusted.
I am looking at different extruders for my Taz, not so much for the bowden design, more for visibility of the nozzle to the part and better control of the indeed of the filament. I would like to add a sensor to ensure the filament is moving.
I didn’t really answer your question. No, not for the issue your seeing. I know it looks like it might be the filament hanging up or slipping. It actually looks like theres a vibration issue, but its not. And if it was, there is a setting for adjusting jitter in the interface of the Taz, but pretty sure thats not what happening.
Looks like this: http://reprap.org/wiki/Print\_Troubleshooting\_Pictorial\_Guide#Too\_hot\_2 Cooling issue. My guess is the bed is too hot for this brand of ABS and the long print time of the fine settings. Trouble with cooling the bed more during printing is the likelihood of warping. If the part doesn’t need the fine settings, print it faster with thicker layers. This is how Lulzbot gets away with using ABS so much is they print it wicked fast. Or as they say, stop using ABS and use PETG 
do you think I should turn off the heated build plate after a few layers have already been printed.
I wouldn’t for ABS because it will pop loose from the bed, maybe lower the temp of the bed after a few layers. If its not kept warm it will shrink and pull away from the bed. I still think its too much infill which is causing a cooling issue in that area.
I think you guys are right, it is a cooling issue. Just by putting the printer in a relatively colder environment I’m getting better results, but they are not perfect yet.
https://drive.google.com/file/d/0Bxn9fYNUPBsqUURDSFhicFpxc2s/view?usp=sharing
Looking better! That brand of ABS just looks like it needs different settings for optimal output. I think you’re on the right track. Keep posting as you get new results.
