l1rj

I'm using an Ultimaker S5 to try to print ferroelectrets from black ABS, and I'm having an issue with getting the first layer a consistent thickness. The first layer is generally about 50 μm, which should be doable with the S5 and the head we're using. What I find is that I have no problem getting material to extrude, but the thickness of the first layer will vary anywhere from the correct thickness to being so thin as to be nearly transparent. In all cases there is extrusion, so I don't think this is a problem with extrusion or adhesion, just the height of the head over a build plate that does not have a perfectly uniform height. I have observed that the glass build plate has a small gap between it and the bed in the middle that decreases as you head toward the corners where the metal clips are. Both plates we received from Ultimaker show this minor bowing, so I assume it's just how the plates are normally and that it shouldn't be a problem if the head autolevels correctly. Currently, as a work around, I find I can place the print in the back right corner and then toss "dummy" prints in the center and the upper left and it will increase the depth of the print in the back right, which is mostly OK (but still not great). However, not only does this not entirely fix the problem (even the "good" prints will have some inconsistency), but I'd also like to just be able to print what I want and only what I want so as not to waste time and materials. The pieces in the photo should all be the same. They're just copies made in Cura of the same object.