Coeff a,b,d explanations


#1

Have been printing with my Wilson II for a few weeks now, think i’ve got a really good grasp on most things, but when it comes to bed leveling I cant seem to get a straight answer about the values that it spits out when it’s done leveling.

When the printer auto levels, it gives me something on the order of:

coeff a: -0.0023
coeff b: 0.0034
coeff d: 3.0045

being the math nerd in me, i’m assuming that these coefficients are slope values in some fashion where it can do the mesh leveling method, but can someone tell me what they correspond to? I’m not 100% certain but i think the D coefficient is for the X axis height because it has the largest number, it would have the most throw when it goes to correct. But I cannot pinpoint where to use these numbers to help adjust my bed height to get it more in line where the printer doesnt have to work so hard during the print.

Does anyone have a good reference to an explanation of these outputs in the firmware?


#2

Only a quick answer now - I’ll dig up more answers after work if you haven’t found what you are looking for.

The coefficients aren’t a slope, and don’t represent co-ordinates. They make up a transform matrix, have a dig around in the marlin repo there are some explanations in the issues.