Solved First layer problems

Within reason, yes... a more "squished" first layer is a good thing. All layer heights are relative to the previous one. The ONLY downside to having the first layer squished flat is having it too close so that the extruder can't push out enough filament. That is bad



https://printedsolid.com/blogs/news/37035715-get-your-prints-to-stick-check-your-skirt

 

Actually since almost all slicers default to use absolute positioning. Your first layer does not affect subsequent layers in they way you think it does. Your first layer is only affected by how well your offsets are created, lets say for the sake of argument that in order for the nozzle to be precisely on the bed your probe offset needs to be 4.55 mm, so you go about using the wizard and you want bed adhesion so you tell your printer that the offset is 4.5 mm, that's reasonable. Now you ask it to print the first layer and you have asked for a 0.20 mm layer height, but since your offset is off by 0.05 mm your actual movement above the bed for layer 1 only is 0.15 mm. The printer thinks that 0.15 mm above the bed is 0.20 mm. You get a squished first layer and perfect adhesion. Layer two is ready and it is still set to 0.20 mm, so the head actually moves up 0.20 mm. There is no offset, there is no affect because layer one was squished. The printer doesn't know it is really at 0.35 mm for layer two, it thinks it is at 0.40 mm. All the other layers are exactly the same as layer two. In a perfect world when you are done with the print your 10 mm tall model should really measure 9.95 mm. There is no way for the printer to know anything different because you told it that 0.15 mm layer one is really 0.20 layer one.

All the rest of the layers move in absolute increments, optional info: Layer one in the above example is specified as 0.20 mm it prints wherever you tell it to print but the printer moves Z to 0.20 mm or at least what it thinks 0.20 mm is. Layer 2 is not 0.20 mm up from layer one. Layer two is printed at 0.40 mm, at least that is what the printer knows, layer three is not 0.20 mm above layer two, it is printed at 0.60 mm. That is why you can't say the position is relative, it is absolute. In effect all your layers are 0.20 mm above the previous, and you can think of it that way it makes it easier for you, but that is not how the printer prints it.

Additional note: You can change the positioning to use relative dimensions, but that is not the default behavior with 3D printers. Some say there is effectively no difference printing absolute or relative but the default and generally accepted method uses absolute positioning.

 

Yes, it is a more simple way to relate to the effect Not a precise definition of what is actually going on behind the curtin