I’m experimenting a bigger Z step to reduce printing time of simple extruded objects (object where layers don’t differ that much. I made a new quality with a Z steps of 0,21mm as I read that the combination of stepper motor and thread used work best with a Z step of multiples of 0,105mm.
With above in mind my question is why is the first layer set by default to 0,20 and not 0,21?
b.t.w. I really got a good results with the bigger Z-step in half the time. I only forgot to raise the temperature with the first print and instantly heard the filament motor chunking when the print started. After raising the temperature with 5 degrees I only heard chunks a minute a part. I’ll try to up the temperature an other 5 degrees on my next print.
I didn’t answer your first question but simply demonstrated that is ought to be framed as why 0.2 rather 0.2025. I don’t know the answer to that question. It may be because it is relying on the stepper motor micro-stepping or it may be that the vertex version of repetier just converts 0.2 to 0.2025 You will have to wait until someone with more knowledge answers
Layer Height: 0.105 or 0.21 (~=0.1 or 0.2 mm quality)
First Layer Height: == Your height between nozzle and the bed (I have the same 0.27 for both 0.1 and 0.2 quality)
First Layer Extr Width: I have 100% for both. >100% will extrude some more BUT the width between 2 lines will be wider on the first layer.
@largab I don’t think the first layer height is the distance between your bed and the nozzle, as the platform drops the specified distance when starting the first layer. Fot myself I won’t tweak bed height and ‘First Layer Extr Width’ as both ABS and PLA both stick to the bed very well with the current settings (maybe a bit to well for PLA when printing object with big footprints :)).
As rrekwa mentioned my questions are:
Why de default setting aren’t true multiples of the Z-step?
To which magnitude (10^-n) do the repetier software and firmware control the printer?
What value for Z does your printer show during the first layer?
I think the reason the first layer high has to be about the same as the distance between the nozzle and the bed is that by default settings the extruder extrudes double the filament on the first layer.
If I understand correctly Z values should always be multitudes of the 0,0075 for best quality, as this is the smallest movement of the printbed.
I think the reason the first layer high has to be about the same as the distance between the nozzle and the bed is that by default settings the extruder extrudes double the filament on the first layer.
It does not extrude “double the filament”
If You studie the first layer in Repertier with different “First Layer Extr Width:” i.e. 100%, 150% or 200% You will see that it does not change the height, only the extr area (width*height there height =constant) and the width between 2 lines on the first layer. The volume does not change i.e. Extr area * Length.