Page 1 of 1

Print quality troubleshooting.

Posted: Mon Aug 21, 2017 8:12 pm
by TheDon
Hot end temp : 185
Bed temp 60
Filament AMAZ3D White PLA
File: the boat we all love
Stock .5 nozzle
.25 layer height
Printing onto PEI
RS V3

Can someone give me a clue as to why I'm getting not smooth sides? I need to order a .4 nozzle very soon. This filament is also rather stringy but that doesn't bother me too much.

Re: Print quality troubleshooting.

Posted: Mon Aug 21, 2017 8:12 pm
by TheDon
And yeah...my iPhone uploaded the photo upside down. Oh well.

Re: Print quality troubleshooting.

Posted: Tue Aug 22, 2017 5:40 pm
by lightninjay
Could be that one or more of your belts are too loose.

Re: Print quality troubleshooting.

Posted: Wed Aug 23, 2017 9:37 pm
by Fughazi
I just logged into my account for the first time to post the exact same question! I'm just going to follow along here.

It looks like the inconsistencies begin at the beginning of each layer, right after the z-seam. My machine is a MAX V2 running stock firmware. Models sliced with Cura. I've ruled out anything to do with the hotend because I recently upgraded with a V6. I tried lowering accelerations and slowing speeds dramatically. I also tightened my belts. I attached my extruder in a flying configuration, so the bowden tube is extremely short. None of these things made a difference.

Any suggestions would be appreciated!

Re: Print quality troubleshooting.

Posted: Wed Aug 23, 2017 10:13 pm
by Xenocrates
For the V2 (I know TheDon's is a V3, looking at his post history, so this isn't the problem, and it is polite to not mix different machines in a thread, and to post which one since it does matter), it may be that the bed temperature is oscillating, causing it to expand and contract, due to a mis-cut hole in the center of the upper plate just below the thermistor. A bit of tape over it, which can be accomplished just by taking the bed off the top, will usually stop that problem.

Re: Print quality troubleshooting.

Posted: Wed Aug 23, 2017 10:46 pm
by Fughazi
Xenocrates wrote:For the V2 (I know TheDon's is a V3, looking at his post history, so this isn't the problem, and it is polite to not mix different machines in a thread, and to post which one since it does matter), it may be that the bed temperature is oscillating, causing it to expand and contract, due to a mis-cut hole in the center of the upper plate just below the thermistor. A bit of tape over it, which can be accomplished just by taking the bed off the top, will usually stop that problem.
My bad, I made the assumption that he had a V2 as well. Even then, my pictures don't quite do it justice but my problem is identical to his. I will make my own post if this doesn't go anywhere.

I actually had the exact problem with an oscillating bed temp a little while ago and fixed it with a PID tune. It causes a banding effect, but it is different than what we are experiencing here. This is much more random. I should add that I could print the model several times over, and the inconsistencies would occur in the same spots. Changing z-seam alignment can affect their location, but they will appear in the same spot while using the same gcode.

Re: Print quality troubleshooting.

Posted: Thu Aug 24, 2017 12:42 am
by Xenocrates
The oscillation is in the actual temp and applied power, due to the power supply cooling fan kicking on and chilling the thermistor slightly, instead of cooling the whole bed off, causing the controller to apply more power.

However, it sounds more like either an extrusion multiplier issue, a slicer issue, or perhaps a mechanical oddity. I know that a layer height related to the golden ratio was experimented with as a solution, and that the Duet family of controllers eliminates vertical banding and helps mitigate the horizontal banding, but I'm unsure if either will actually solve your problem, so at least for the Duet, let's keep that in reserve, as the printers are fully capable of better prints than this with the stock controllers.

Have you tried another version of Cura, or another slicer such as KISS?

Re: Print quality troubleshooting.

Posted: Thu Aug 24, 2017 11:48 am
by TheDon
I'm thinking mine is extrusion multiplier. I adjusted my coast settings and saw a big improvement but I think once I nail the extrusion multiplier it should be good.

I'm using S3D primarily, I paid for it so I am sticking with it

Re: Print quality troubleshooting.

Posted: Thu Aug 24, 2017 9:09 pm
by TheDon
well I have no idea how to fix it.

I tried yet another 20mm cube in vase mode with no top or bottom and my extrusion width is set to .5 with a .5 nozzle and my calipers are reading .63-.65

Re: Print quality troubleshooting.

Posted: Thu Aug 24, 2017 9:21 pm
by Fughazi
TheDon wrote:well I have no idea how to fix it.

I tried yet another 20mm cube in vase mode with no top or bottom and my extrusion width is set to .5 with a .5 nozzle and my calipers are reading .63-.65
Imo, that method of setting extrusion does not give accurate results. I recommend double checking esteps, setting exact filament diameter in slicer, and then printing a 100% infill cube and adjusting flow rate if necessary.

Regardless, I don't think that's the problem. I've been using Cura and tried a different slicer as suggested (Slic3er Prusa Edition). As you can see, the problem has pretty much disappeared. That was with the aligned z-seam setting that is the default in slicer. I'm printing one with the "shortest" z-seam setting to see if it continues to work well. Try it out to see if S3D is causing the problem as well.

One interesting thing I noticed is that the delta wavy wall artifact is much more pronounced with Slic3r than with Cura. Does anyone know why the slicer has any affect on that?

Re: Print quality troubleshooting.

Posted: Fri Aug 25, 2017 8:53 am
by Xenocrates
Some slicers have different segment lengths that they issue. S3D for example, has been known to issue multiple single micron moves in a row (Yes really, it caused lockups on the smoothieboard due to the useless moves choking the motion planner). Different segment lengths can be interpreted differently, especially when microstepping gets involved. You can try the following strategy, which has helped with artifacts in the past:
I used to set my steps/mm according to what the caliper told me, but recently when looking at this issue I've discovered that you can get moire effects. Mine was set to 161 steps/mm, when the calculations say 160.

The 0.1618 layer height is calculated as follows:

80 usteps/mm = 5 steps/mm (at 1/16 microstepping)
= 1 step / 0.2mm

Golden ratio * step size = 1.618 * 0.2mm
= 0.3236

Halve this to get a reasonable layer height:
= 0.1618 layer height.


The magic is in the golden ratio, it spreads out the single step peaks so that they don't line up with subsequent layers.

As you have 80.7 usteps/mm, the layer height you should use is:

0.1604 mm.