Initial layer height

[Julian7 1]

I have a Prusa-type filament printer (Geeetech).

 

I have been experimenting with the clearance between nozzle and bed and have found that a smaller clearance produces a better adhesion brim. It seems to stick more securely to the glass plate and, being thinner, is easier to remove.

 

The problem is that the Initial Layer Height in Cura is set to 0.3mm, which means my models are slightly shorter in the Z-dimension than they should be. I can set this to, say, 0.1mm (Custom Settings) but I have a question. Does this just affect the slicing calculation (i.e. more layers), or does it also affect the extrusion rate for the initial layer and/or the Z height of subsequent layers?

 

Thanks,

 

Julian

[gr5 1,249]

If you set initial layer height to 0.3mm it extrudes 3X as much filament on the first layer versus if you set the initial layer height to 0.1mm.  That's not what you asked but I think it answers your question.

 

Also it will set the Z=0.3mm if you set initial layer height to 0.3mm.

 

There is an "initial layer flow" feature which you can set to 200% for the first layer if you want.  And then you can also set "initial layer horizontal expansion" to about -0.25mm (for a 0.4mm nozzle).  If you play with all these enough you can have it all.

 

By the way, yes, squishing harder on the first layer greatly increases adhesion to the bed.  I have a video about this:

 

[Julian7 1]

Thanks for that comprehensive answer and the link to the very helpful video. I understand now. 

 

Julian