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  1. When you say 'and improved my prints', what were the symptoms? What looked bad before and what is the appearance now that it looks better? The extrusion width will always be greater than the nozzle diameter, unless the layer height is close to the nozzle diameter. By changing from 0.4 to 0.45 in Cura, you actually changed the path spacing as well as the amount of plastic being pushed into the nozzle. Path spacing = width for the Cura engine. So I would guess you had too much overlap between adjacent passes. You should also adjust the extrusion multiplier for even bette
  2. Yes, cura does care about the shape of the filament. Instead of asking for filament diameter, a more accurate question would be 'filament cross-sectional area'. So, if you were to use square filament for whatever reason, you can rearrange the equation below to solve for D, or equivalent diameter, and that would produce exactly equal G Code values.
  3. Equating the diameter of the nozzle to the length of a side for a square nozzle does not make a lot of sense. The key parameter here is area. Remember, we want the volumetric flow rate to be equal. So, for a nozzle with diameter, D, the equivalent square nozzle would have side length S equal to: S = D*sqrt(pi/4) So when you say 'the lines require slightly different amounts plastic', it is because the dimensions of the square nozzle are incorrect to begin with. According to this equation, for any linear distance of extruded filament, the amount of material
  4. The E values of all FDM, filament based printers are based on the same equation. That is, the conservation of volumetric flow rate: where 'deposited' referes to the material exiting the nozzle. The tricky thing here is that different slicers use different equations. I have found that the biggest difference is in the cross sectional area of the extruded mass, i.e. Aextrusion. That is why I started this post. The next biggest equation is how path spacing is calculated between adjacent paths. You need both equations to understand how the material
  5. This is an ideal world, which the slicer looks at to make its calculations. However, in reality, the cross-section will never be truly rectangular. The center-to-center spacing between lines should therefore be slightly less than the extrusion width. Otherwise, the planar interface between lines would be exactly planar contact with minimal bonding between adjacent paths. But of course, for calculations I have seen that it makes the calculations easier when the spacing is equal to line width. This would allude to the fact that the width is actually larger than what is being used
  6. Hello, No, you are exactly right. Cura will overestimate with a rectangular cross section compared to a circular cross-section. So, if you are extruding more material with Cura's estimate, something else has to change. That something is the distance between path spacings ( I would guess, but Cura's code in not open source). If you look at my post on Slic3r versus MC, the path spacing between adjacent extrusions are also different. Slic3r calculates path spacing as a function of both layer height and extrusion width, while in MC it is equal to the nozzle di
  7. Burtoogle, I saw your reply, thanks! So it is a rectangular cross section, Area = width * layer height.
  8. Hi Everyone! Wow! Good replies! There are actually a lot of things that can influence the Gcode values, but if we stick with the basics and simplest of situations: 100% infill fixed layer height user-input extrusion width OR nozzle diameter filament diameter (flow multipliers are just arbitrary numbers multiplied by the following equations) You will find that open-source slicers, like Slic3r, have values computed as such: Slic3r flow calculations, w = width, h = layer height, D = filament diameter Where the E-
  9. Hello, I was wondering how Cura computes the E values for the gcodes. What type of cross section does the software assume for the extrudate mass? Thanks! Tim
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