Layers not smooth

[Roy]

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!

[noiseboy72]

Looks like some play in one of the axis. There is a bit of wobble going on as well.

I don't think that temperature is a problem and TBH 1 degree is less than the stable temp that the printer will sustain anyway. You will find if you measure it that is will vary by about 3-5 degrees over the plate (Quite possibly more) and will cycle over a similar range due to the binary nature of the heating.

[Roy]

Shouldn't wobble affect all sides? One side along the same axis is smooth, but the other side is not.

[noiseboy72]

I think that either there is backlash at the end of each "pass" - assuming it is printing front to back, or there is a retraction issue, with too much filament being extruded at the end of the pass.

In terms of the wobble, from the photos it looked like at least a couple of the sides had quite wobbly sections. Certainly I can get better results with my £265 CTC3D and I would expect a much more expensive printer like this to do much better.

[Roy]

Well I didn't buy the printer; it's in my school's 3d printing labs. the only printers that are there are a few lulzbot minis and 3 taz 6s and an ultimaker, but the ultimaker has a 0.8mm nozzle and I need at least 0.4mm nozzle. The minis aren't that great either. I forgot to mention that it prints the first few millimeters perfectly and then as the height of the print increases i get that, and then a few millimeters later everything seems to be printing just fine as you can probably tell from the photos.

[noiseboy72]

Have you tried a different Lulzbot? At least this will rule out if it's a machine fault as I doubt they would all be the same.

[Roy]

I tried all of the three tazes and all of them give the same result, some worser than others

[noiseboy72]

Not sure then!
I wonder if the slicing is not perfect. Might be worth turning the object through 90 degrees, trying some more support material or altering the resolution?

[Roy]

Will maybe using a different slicing program help

[noiseboy72]

If you want to send me the STL, I can try printing it on my printer.