Originally shared by René Jurack
Smooth Toplayer without visible tracks: Just set extrusion-width and layerheight to a crazy tiny setting for the last couple of layers.
In the pictures: 0.1mm extrusion-width / 0,05mm layerheight / 3 toplayers / nozzle in charge was a 0.3mm microswiss.
Filament was blue PETG, the layers are so thin, you can see the layers beneath the surface. Under the microscope, it looks like transparent filament, but it isn’t 
I don’t use Cura, but isn’t that what its “Ironing” (a.k.a. Neosanding) setting does?
@kongorilla yeah, though ironing only does this for the very top surface (not for 3 layers as op suggests).
ironing works great for pla but I’ve never tried it on PETG. to be honest my surface quality with PETG is so good already I can’t imagine ironing doing anything good for me
@Lukas_Mathis ok, but as I said my surface quality is fantastic with PETG, so much that I suspect any changes would reduce quality rather than improve it.
@Lukas_Mathis I think I just happened to hit on the right material for my setup. I use MakerGeeks Maker PETG, print at 260C onto a 70C bed with a 0.4mm nozzle. I print at 50mm/s and would always need ironing to get a nice surface with PLA but with this PETG it’s just beautiful without it.
clean, smooth top layers; supports that just slide off; it’s wonderful.
my only two issues with PETG: warping and heat creep. even with the heated bed I have some warping issues to contend with, but the heat creep is killing me. I get liquid PETG oozing up through the threads of the heat break and out at the top surface of the heater block. I plan to upgrade to an e3d v6 (I’ve got a v6 lite now which is really only rated up to 245C for this very reason)
@Jared_Eldredge Love me my Maker Geeks filament. Cheap and still pretty good quality. Try 80 C on the bed for PETG, I was also having warping issues at lower temps.
@Lukas_Mathis I pretty sure it’s a clone. it’s the stock hotend and nozzle from xmachines (yeah I was one of the lucky few to get a printer)
Rene great up close shots. Question, are the top layers brittle, malleable or is it still ridged?
@Jeremiah_Coley It has a matte finish without any visible lines or grooves.
