Is a flattened Skirt possible with CuraEngine/Host ?

P_O

Hello all,

I like to work with a nicely squashed first layer (about half of the height of a regular layer, and with the extrusion expanding the material sideways for good contact). I also like to have a skirt (of 2 or 3 lines) around my models, as that lets me do some quick last minute leveling adjustments before the actual printing starts.

However I seem unable to achieve these two things at the same time with Host/CuraEngine, because the slicer seems to refuse to generate any Skirt pass if the "First Layer Height" setting is set to something lesser than the "Layer Height" setting. As shown here :

Of course I do see the option to expand the "Extrusion Width" of the first layer. But what does that actually mean, since the diameter of the nozzle is fixed ? Is that causing an increase in filament flow ? Or perhaps it is doing some kind of backwards math, reducing the height of the first layer according to the desired "thickness" value ? But I don't seem to find anything like that in the resulting gcode.

This is all very confusing - I would love to get some clear explanations on all this.

Thanks !

Repetier

Yes, seems like skirt vanishes if it gets below 50% of regular layer height. We just pass parameter to curaengine so can not give more details here. Actually I do the opposite with first layer height and make it higher to compensate uneven bed. Same is first layer width for. It makes wider extrusion by increasing flow rate so if distance it a bit wider it still has good contact to bed or if it is same it presses more against bed. Higher height or width is the normally preferred way to solve this - coming closer to irregularities is not what you normally want, especially if bed has good adhesion. Then close distance can stick so well that it gets difficult to remove or you might even get contact to bed depending on shape and z calibration. But that is up to you which solution you need. Also depends on bed material.

P_O

Hello and thank you for another answer to my barrage of questions.

I think I am just used to leveling as high as possible, therefore used to getting that satisfying "squished" first layer and skirt as mentioned. But I should have probably mentioned that I am mostly working on rather small parts (5 to 10cm max) therefore I am not getting big variations on bed level. So I suppose I will indeed play with the "First Layer Extrusion Width" setting. I would simply suggest to be a bit more clear in the help popup as to what that actually does (since the width is really just the consequence of an increased flow / extrusion speed, indeed).