strange artefacts on the surface - delta kinematic [solved]

CaiJonas

Hi guys,

I'm at the point not to know what I can do next to get rid of the following problem:

As you can see I have this strange artefacts on the surface in x and y direction. Maybe some knows what to do.

My latest setup:

delta printer
0.9° motors
bondtech extruder
very high quality pulleys and smooth idler pulleys and belts (HTD 3m from Maedler Germany)
running at 24V
original Hiwin linear rails
precision piezo bed leveling sensor

What I tried:

varying speed, jerks and accelerations settings
tried different layer hights
tried other belt tensions
changed extruder to titan
tried other extruder microstepping
tried other axis micorstepping
run auto pid tuning for bed and extruder
calibrate non linear extrusion
calibrate pressure advance
changed belts and pulleys from GT2 6mm width to 9mm width and then to HTD 3M
tried other filaments
checked if bed or joints are loose

I'm very into 3d printing and I think I know what I do but now I am at a point where I do not have any other ideas. It is not my first delta printer.

I'm not shure if it is a hardware or a software/electrical problem. At this moment I guess I have these problem since the 2.0x firmware update. The prints before doesn't have these artifacts, only the normal small ones which comes from the delta kinematic.

I'm grateful for every tip!!

Best regards
Cai!

dc42

If you think that artefacts only happened after the firmware update, please can you test using firmware 2.0, 2.01 and 2.02 to see which is the first version that has this problem. There was a bug fix in firmware 2.02 that affects extrusion, so it's not impossible that the artefacts you see are a consequence of that.

What layer height are you using? It's usually best to choose a multiple of the full step distance. This will be 0.1mm if you are using 20-tooth pulleys, or 0.08mm if you use 16-tooth pulleys - although my delta uses 16-tooth pulleys and I find that 0.2mm works well.

CaiJonas

It does not depend on the firmware version. I did print the same gcode with 2.0, 2.01, 2.02 and all look the same and all does have these artifacts. I used a layer height of 0.24mm. Is that correct when I am using 14 teeth htd 3m pulley?

Here is my config.g, maybe there is something wrong.

0_1546867397765_config.g

Best regards and thanks for the help so far

Cai

Phaedrux

I'm not sure if it matters, but you seem to have a lot of extra spaces in some of your commands.

M350	X16	Y16	Z16		I1				; Configure microstepping with interpolation for axis
M350				E32	I0				; Configure microstepping with interpolation for extruder
M92				E1630					; Set steps per mm for extruder 825

Actually, all of your spacing looks a little strange, are you using tabs instead of spaces? Or is it just multiple spaces in places?

CaiJonas

@phaedrux
I'm using tabs, but with the new dwc it doesn't work anymore. For me it looks more clean.

dc42

Does the pitch of the Z banding relate to any physical properties of your machine, for example a whole motor revolution, or 4 full steps of a motor?

Does the horizontal pitch of the diagonal banding relate to anything ni the extruder, for example a whole revolution of the motor, or a whole revolution of the hobbed gear?

I don't think it's a firmware issue, but to make sure, you could try reverting to the firmware you were running before these artefacts started appearing.

CaiJonas

@dc42

I'm pretty shure you're right. In 1 out of 10 cases it's not an hardware related problem. I will print some pulleys and idler pulleys just to see if that change the pattern of the artifacts. I drilled the hole thrue the pulleys by myself and that is not the best way.

BTW is there a known internet shop where I can buy HTD Pulleys with a hole of 5mm? My dealer could drill the holes but that is 180€ without taxes for 6 pulleys

Dougal1957

@caijonas yes try Robotdigg

CaiJonas

I changed the idler pulleys to printed ones and as aspected, the artifact are less visible and look different. So I have to change the pulleys. They have a wobble. Thanks guys, I will try the ones from robotdigg.