Blobs and under extrusion with S3D

dc42

Your extruder speed and acceleration are set very high. Are you sure you are not getting missed steps during retraction?

pogo1213

@dc42 I started far below as noted below:
M566 X900 Y900 Z12 E120 ; Set maximum instantaneous speed changes (mm/min)
M203 X6000 Y6000 Z180 E1200 ; Set maximum speeds (mm/min)
M201 X500 Y500 Z250 E250 ; Set accelerations (mm/s^2)
M906 X800 Y800 Z800 E1200 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

and I was getting similar results that was discussed here:
https://forum.duet3d.com/topic/849/tweaking-for-perfect-jerk-accel-pressure-advance-blob-removal/28

I have dropped my retraction all the way down to 0.2mm but after the retraction it under extrudes for ~15mm. I have a print running with a higher pressure advance to see if that makes a difference

Phaedrux

@dc42 I only got hiccups when testing 256 microstepping. With 16 Ive never noticed any.

pogo1213

i attempted 0.2 pressure advance and it looked better so Im attempting 0.5

Phaedrux

@pogo1213 are you using a Bowden setup or direct drive? 0.5 is quite high for a direct drive.

pogo1213

direct but Im running out of possible solutions

pogo1213

0.5 was to much but 0.2 has worked pretty well but it hasn't solved it just made it look slightly better

pogo1213

I have retraction down to 0.2mm without stringing and no longer leaving blobs just leaving a void immediately after the retraction

dc42

@pogo1213 said in Blobs and under extrusion with S3D:

I have retraction down to 0.2mm without stringing and no longer leaving blobs just leaving a void immediately after the retraction

You can use "Extra restart distance" to avoid that.

zerspaner_gerd

I also have a larger Z-seam with S3D.
With Cura I have much smaller nicer ones.

I could not find any differences between the two gcode files.

Here are the two gcode files:

1_1532300304525_S3D.gcode
0_1532300304525_Cura.gcode

pogo1213

@zerspaner_gerd what type of extruder?

pogo1213

This post is deleted!

pogo1213

After a large amount of tweaking Retraction speed and distance (ending with 0.2mm distance and 5000mm/min speed), Pressure advance (0.05) and extra restart distance (ranging from 0 to 0.2, settling on 0) I still have a small seam. Any other suggestions?

https://drive.google.com/file/d/176qYIU3DtLloxzfob3uDFD5SV3tU5ere/view?usp=sharing

https://drive.google.com/file/d/1rS7onyxYcRK3mBEMIRk2-sgEGEXSywZ0/view?usp=sharing

https://drive.google.com/file/d/1-vrav9f9cwBVXSd_euZr62YmYs5Tix7e/view?usp=sharing

Phaedrux

That's a quite good seam actually. You'll never completely eliminate it. Now the trick will be trying different options to hide it in the model. I'm not very familiar with simplify 3ds options but I assume it's similar to slic3r and Cura and gives you the option to try and hide it on the sharpest inside corner or align it to a specific place. It'll depend on the model on which will work best. On angular shapes I find it easier to align it to the sharpest corners. On more organic shapes I usually just align it to a single side.

Have you also tested for stringing between travel.moves yet? 0.2mm is fairly low. How about an actual print?

pogo1213

I ran a retraction test (4 spikes in a 20x20mm square) with great results at 0.2. I also printed a few parts in pla with no issue, PETG Im bumping it up to 0.5-0.8 to get great results.

Phaedrux

I'd say you're good to go then. Print a benchy or some other actual model and see how things look for further tuning.

pogo1213

After playing with retraction and pressure advance everything looks good when its not moving between parts. When it is it comes out like this
https://drive.google.com/file/d/13OBB-CuOU5PKmGub2PCu8fpjo6xvNbqS/view?usp=sharing

Any suggestions?

Phaedrux

What is your travel speed in the slicer?
In your config.g do you have an M204 command to specify print acceleration and travel acceleration?

200mm/s or more for travel moves is probably desirable and acceleration values 4000 to 6000mm/min. Greatly reduces the time available for strings to ooze out.

M204 P1000 T5000