Bed levelling in 1.1.0 rc3

Is there anything different in how this version applies bed correction after g29? I notice it generates and outputs a bed compensation matrix. Is it adjusting the bed by applying a plane to the z values or is it adjusting different areas of the bed by differing amounts ie compensating for a truly uneven bed?

The reason I ask is that this is how bed levelling is handled in Rich Cattell's marlin fork for deltas and it improves first layers immensely. We all think our print beds are flat but this is not often true.

If it does use this method then there is every reason to use many more than 9 points when probing.

Well I've answered this myself by experimentation, if I trigger the sensor at one point before the bed gets to it then print a bed level test the entire bed level is affected not just the level in this area.

When might we get a full bed surface compensation option? Why can't the code from RC's fork be integrated into mainstream marlin? I accept the arguments about flat beds and true objects but if you have a large printer a truly flat bed is difficult to achieve.

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DjDemonD
Well I've answered this myself by experimentation, if I trigger the sensor at one point before the bed gets to it then print a bed level test the entire bed level is affected not just the level in this area.

When might we get a full bed surface compensation option? Why can't the code from RC's fork be integrated into mainstream marlin? I accept the arguments about flat beds and true objects but if you have a large printer a truly flat bed is difficult to achieve.

It sounds like you want to be using the Mesh Bed Leveling. And incidentally... I'm working on a High Resolution Mesh Leveling System for Delta's. But it should cross over to Cartesian machines fairly easily.

Having just read this mesh bed levelling it seems as if this is exactly what I'm seeking however why it can't be done by auto probing when others have already done the work I do not understand. However I am looking forward to this being an option with auto probing in the future.

Edited 1 time(s). Last edit at 02/26/2016 03:33PM by DjDemonD.

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DjDemonD
Having just read this mesh bed levelling it seems as if this is exactly what I'm seeking however why it can't be done by auto probing when others have already done the work I do not understand. However I am looking forward to this being an option with auto probing in the future.

Mine will do Auto Probing of all areas within the DELTA_PROBABLE_RADIUS (for Delta Printers). It will have a fast and efficient way to get the rest of the Mesh defined (whether you have an LCD Panel or not). And there will be other goodies too. I'm writing the code so it will be easy to cross over to the Cartesian world. But I'm doing it first for Delta's.

Okeee, so develompment on Delta is still alive.
This is nice to hear.

And yes DJDeamonD, that's also my question: why not merge the working solution from Rich Catell into Marlin.. I have no ideea.
Especially since the G29 in Marlin seems to have the "hang in the air" issue (it fails on the autolevel).

My knowledge is not good enough to debug Marlin 1.1.0 RC6 but it shuould be good enough to "DuctTape" the autolevel from Rich Cattell into the latest Marlin....