S-curve acceleration?

Is s-curve acceleration on by default in the pre-built binaries?

If not, how do I enable it? or do I need to compile my own binary?

It is enabled by default in latest releases.

So apparently S-curve and linear advance don’t play well together.

Are there instructions anywhere on how to compile a custom build? I’ve built Marlin from code before, but that got flashed via direct USB connection, not microSD…

Nevermind. I found the build from source instructions.

Do you have some sources for that? Do you disable S curve?

Yes see discussion here:

[BUG] Linear advance incompatible with S-Curve acceleration · Issue #14728 · MarlinFirmware/Marlin · GitHub - https://github.com/MarlinFirmware/Marlin/issues/14728

The short version is that linear advance expects trapezoidal acceleration, which is the default without s-curve. Some people say “LA + s-curve” is better than “no s-curve and no LA” but not as good as “no s-curve with LA”.

I may try to build my own advi++ without s-curve sometime this week to try it out.

By default, ADVi3++ uses a K factor of 0, i.e. no linear acceleration. So by default, S curve should be OK.

I just been playing with LA, so regarding above is it better just to leave it off at 0?

Seems to slow down the print no matter what speed I set it at.

I would add my prints are coming out amazing. Just very slow.

Is there any tuning to be done with SCurve? If so is it possible to get the options on the LCD in a future release

Will do some speed/quality comparisons tests with LA @ 0 and 0.1