Linear Advance questions

Hi, I am interested in tuning linear advance on my printer running RAMPS with Marlin 1.1.9 release

I tried generating test patterns using this page: [marlinfw.org]

The first one I did in the default range 0-2, then I tried 0-10, and even 0-100, and I never see the effect of under/over extrusion going away or reversing.

Does this not work with higher acceleration values? I have 3000 mm/s^2 accel on XY and 10mm/s jerk. The extruder is a greg's wade 1.75mm (no bowden).
I was testing 15mm/s to 40mm/s speed difference.

Is it possibly some conflict between extruder vs XY accel / jerk?

edit: Is there a setting I missed in Configuration.h to enable this in the first place?

Also should I be running the 1.1.9 bugfix instead? I never quite understand why the branch with fixed bugs would be the one that is cautioned *against* using on the download page.

Edited 2 time(s). Last edit at 09/14/2018 12:37PM by peepsalot.

Did you enable it in "Configuration_adv.h" ?

you have to remove the "//" before "#define LIN_ADVANCE" to make it work.

Hope you get it running.

That was the issue. I think I had searched for an enable setting in Configuration.h and not finding one assumed it was just a thing that could be set on the fly.

Also was reading through the marlin docs on linear advance, taking it step by step. It shows the setting to enable in Configuration_adv.h but only after all the sections about how to calibrate it. Slightly confusing.

I tried to start using Linear Advance in the new Marling. I calibrate everything and tried in the firmware code to set K to 40. When I then compile in Arduino IDE I get this message: LIN_ADVANCE_K must be a value from 0 to 10 .
If I use 4.0 then every thing is OK but I don't now the effect at printing.

I also have this error when activate the linear advance: #error "LIN_ADVANCE (1.5) no longer uses LIN_ADVANCE_E_D_RATIO.

What i'm doing wrong.

Regard
Ola A

The linear advance calculation changed in Marlin 1.1.9 (from linear advance 1.0 to 1.5) and the units changed along with it.
So you will need to calibrate for a new K factor value if you just updated to 1.1.9.

Everywhere you read about calibrate the K value the talk about 40, 50, 60 and so on.
But if I try to use this I got the error message. All tools give this type of values.
Where can I find tools I can use and give me the right values.

Thank you for your replay :-)

Again, that's because they are talking about version 1.0 and you are on version 1.5.

Read the marlin wiki for linear advance, and use this to generate test pattern:
[marlinfw.org]

PAY ATTENTION to the line that says "Lin Advance Version:"
It will default the min and max K-factor to typical the value range depending on the version you select.

OK :-)
Thank you for replay and link. I'm going to try the test pattern.

Yesterday evening I ,(my wife complained) configered the files Configuration.h, Configuration_adv.h who came with 1.1.9. Earlier I have used this files from 1.1.4. After that I didn't got the earlier errors when activate Linear Advance.

I think this files start too have to much code connected to the version of the firmware. It takes to long time too configure them every time. I hope it's going to be better in version 2.0

Again, tank you for replay and a nice forum :-)

Edited 4 time(s). Last edit at 09/22/2018 09:38AM by OlaA.

Sorry but there was some problems with the emoji. Please erase this.

Edited 1 time(s). Last edit at 09/22/2018 09:42AM by OlaA.

Yes it can be difficult converting Configuration between versions of Marlin.

I always use a diff/merge tool such as WinMerge (Windows) or Meld (cross platform) to make sure all the settings get moved over appropriately and that I'm not missing anything. It can be quite tedious and time consuming though to look over the entire diff though.

Quote
peepsalot
Yes it can be difficult converting Configuration between versions of Marlin.

I always use a diff/merge tool such as WinMerge (Windows) or Meld (cross platform) to make sure all the settings get moved over appropriately and that I'm not missing anything. It can be quite tedious and time consuming though to look over the entire diff though.

Thank you for this tips :-) I'm going to try them out next time.

Mvh
Ola A.