Cura - Help with 1mm nozzle, cannot make it slow down on 90d angles

Hello.
I am trying an 1mm nozzle for the first time on my A350.
I find that there is trouble where the machine have to turn more than 45degrees.
I read that you can make it slow down on angles using the print jerk settings. Default setting is 20 and I have tried down to 3mm/s but seems to have absolutely no effect.
So is there any recommendation on using this 1mm nozzle?
Thank you,

This machine does not use jerk but instead uses junction deviation. The JD setting default on the machine is adequate and I don’t know of anyone that has had to change it. In my testing it’s optimal.

A typical value is 0.02, the range you listed is far too high.

Please clarify what you’re talking about. Post pictures to illustrate. A wild guess I have is that your linear advance is wildly out of range and causing the issues as it comes into play when there are large changes in acceleration (as would happen on sharp corners).

Maybe start by running a lin adv test: https://teachingtechyt.github.io/calibration.html#linadv

I assume if there was excessive play in the rail brackets that this might also cause problems?

-S

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Hello. Sorry for the delay, and thank you both for replying.
I went to a work trip, then when I came back had to print some stuff so had no time to do more testing with the 1mm nozzle.

However, I still want to know how to make the printer slow down on 90degree angles.
Here are the Jerk settings I was talking about. In the capture the default values are shown. I tried with lower values but they seem to do nothing.
Also, before starting testing I tried to do linadvance calibration but results were bad so I left it at 0.

I still want you to clarify the points I made in my post. The numbers you give and the examples you give contradict how the machine actually works.

As mentioned before this machine does not use jerk. The screenshot you’re providing of Cura settings is irrelevant and the machine will ignore any commands that attempt to set jerk limits.

Perhaps some education is in order, you can start by learning what junction deviation is here, as that is what effectively limits jerk by dynamically calculating jerk and holding it to a limited virtual “junction deviation” between two line segments:

A more advanced description is here:
https://reprap.org/forum/read.php?1,739819

and more advanced yet here:

Once you understand how acceleration and junction deviation work together then if you are having issues with corners you will understand how to adjust the parameters to optimize them.

If you don’t want to have to understand junction deviation and you just want to turn knobs and see if anything changes I’d suggest using this tool, configured correctly
https://teachingtechyt.github.io/calibration.html#accel

However, as previously mentioned, I think you’ll find it takes a very large change in JD over the firmware default to effect a visible change, hinting at something else being the issue.

I know what you mentioned, but you still requested pictures.
Do you mean a picture of a bad looking corner then? .D

I think at this point you should educate yourself on junction deviation and do some testing. The acceleration testing tool I linked above is the best way to do that. There’s no way anyone on here can look at a picture and tell you what number to set it to.

However, I think you should keep in mind that while you originally started looking into jerk, which would be closest to junction deviation in this machine, I think you’ll find acceleration has more affect. I reduced my acceleration to 750 and got a noticeable improvement with an acceptable sacrifice of print speed. 500 was better yet, but sacrificed too much speed for the small increase in quality.

The picture I was referring to was based from this comment:

Since I have never heard of anyone else having that specific problem on this machine I’m not sure why that lead you to investigate jerk, other than it allows you to slow down. A picture would allow someone to make their own conclusion as to what the problem is.

Regardless, use the acceleration and jerk tool for a variety of settings, and you should find one that works for you. Most everyone on here has an acceleration calibration test, it’s considered a prerequisite in using any 3d printer after calibrating e-steps, flow rate, and temperature.