Support / Raft Issue with Slic3r PE
Hello Everyone,
I was trying to print a part with a raft, but I noticed that the first layer of my actual part is much thicker than is set in the layer thickness, and the perimeters are also offset inward with respect to the perimeters on the next layers.
Does anyone know what settings affect this? Why is the interface layer thicker, offset inward, and what how do I change these settings, in addition to the 'overhang perimeter' setting?
Thanks!
RE: Support / Raft Issue with Slic3r PE
[...] I was trying to print a part with a raft
May I ask why you're using a raft? That part looks to have a solid 1st layer that should adhere well on a properly cleaned and calibrated PEI surface. I see rafts used frequently on printers with fixed, often-warped platforms to compensate for hardware deficiencies, but the Prusa printers largely do away with those concerns. Is the 1st layer uneven on the underside?
Can you attach the STL so we can look at it in Slic3rPE more closely?
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RE: Support / Raft Issue with Slic3r PE
Does anyone know what settings affect this? Why is the interface layer thicker, offset inward, and what how do I change these settings, in addition to the 'overhang perimeter' setting?
I don't think there is a particular setting that can affect that. The first layer on a raft is basically all in an overhang mode regardless of the 'Dected Overhang Perimeters' setting.
It makes sense: The printer cannot squish the print into the raft, since it'd be imossible to separate. So it lays the print on the raft from above carefully and that means the extrusion will be round. And that means it'll be the same width and thickness. And since the slicer tries to achieve a 0.4mm (approx) width, it'll also be similarly thick. There is no way around that, because of the physical world, and so there is also no setting.
And as Bob says: Unless you have to, don't use rafts. And don't use single layer rafts if you actually need rafts. They are a thing of the past in most, but a few specific cases.
RE: Support / Raft Issue with Slic3r PE
Hi everyone,
I am printing with a material that is a composite of plastic and metal. The material is rather brittle in its green state directly after printing, therefore it has a tendency to fracture (break) during removal from the build plate.
I have been able to successfully build the part while using a raft as the sacrificial support which is broken in order to remove the part from the build plate, leaving the actual part in-tact.
My question more or less revolves around homogeneity. It makes sense that the layer height would be equal to the nozzle diameter, which is why the layer is also thicker. I simply just want to avoid this inhomogeneity in the parameters. My raft runs at these settings, my part runs at these other settings.
My material also requires a different type of extruder, meaning the pinda probe and bed leveling do not run properly. This adds to the importance and complexity of raft parameters.
Does anyone know how this might be achieveable?
Thanks!
RE: Support / Raft Issue with Slic3r PE
If you set layer height to 0.32 (assuming a 0.4 nozzle), all widths to 0.32 and bridge multiplier to 0.522, you'll achieve the homogeneity you're looking for. The first layer will have the right height and the correct width, but it will be less dense (made of round rather than square extrusion) than subsequent layers.
These settings should be printable, but I have no idea what impact they'll have in terms of print quality or layer adhesion, including how it'll stick to the raft, particularly with your specific material.