Basics - What is a top layer?

Hi. I have a Taz 6 and am currently having problems with pillowing on my flat surfaces. I understand that increasing top layer thickness helps, but if my model has many stepped flat surfaces, is it just the very top one that is classed as the top layer? When the model has small protruberances above the large top surface, would the top layer only be in those parts? Is there a way to increase layer thickness on all the flat areas? Thanks.

The top layer is typically the exterior layer… which could also be a perimeter layer. So increasing the number of top layers (horizontal surfaces) and perimeters (vertical surfaces) will create a more solid exterior surface.

The layers are calculated into the center of the object, therefore the exterior dimensions should stay true.

Hope that helps.

Got it. Thanks. So basically all my horizontal surfaces are “top layers”.

I seem to have found the answer to the pillowing without adding too many extra top laters, and that was by switching the infill pattern to lines instead of grid. That makes the gaps half the size, using the same amount of infill material and time, by only printing in one direction on each layer.

We live and learn.

Yep. Lots a ways to skin a cat.

The issue you’re running into is bridging the infill grid, which can depend on the infill density, layer height and extrusion temp.

A higher infill percentage, will make the grid spacing smaller. These machines will typically handle 5mm, but 3mm is a better gap to span.

A greater layer height will make the extrusion thicker and more rigid when cooled. Therefore .3 will span gaps better than .15. Need the right bridging cooling settings in slicer.

And finally, if you lower the extrusion temps… the extrusion will cool and become rigid faster. Thus freezing the filament in mid-air.

Hope that helps… and saves you a little headache. :slight_smile: