dougconran

I'm using Cura v4.11 to print a PLA disc using an Ultimaker 3. Ideally I would like to print the top surface only with concentric rings, keeping the bottom surface to lines (the top and bottom are slightly different widths and I get an odd kink in the bottom layer if that, also, is concentric). So, first question is: is it possible to limit concentric rings to the top layer only. Secondly, can I get it to print from centre out (or outside to in)? At the moment it will only print inside to halfway out and then outside to halfway in which gives a two-tone affect (I haven't yet tried smoothing because of the additional printing time)

Brilliant! That's it. Thanks, also, for the pointer to the GitHub repository.

I'm using CuraEngine v3.1.0 on Ubuntu 18.04 to slice an stl file and using the ultimaker.def.json definitions file. That file suggests that there is an infill setting called 'infill_sparse_density' with a default value of 20%. When I first ran CuraEngine it generated a huge number of settings which I captured and then modified and used for subsequent slicing. However, whatever 'infill_sparse_density' value I use the end result is always sliced with 50% infill. How can I change the infill density? Any suggestions would be gratefully received - thanks.

That is a brilliantly clear, concise explanation of those settings - many thanks (and the rest of the comment is pretty good as well!)

Thanks for that explanation, it was sort of what I'd thought but nice to have it confirmed. That does, though, bring me on to another question as I'm still a bit confused about the purpose behind the 'layer height' setting and 'initial layer height' setting. From what you are saying I deduce that the 'layer height' is the setting that determines the nozzle height above the build plate and thus the default height of each layer (I know that is obvious but bear with me!). When the printer performs an auto levelling and moves the build plate up until it is just touching the nozzle does it treat that point as z = 0 and then add the (initial) layer height to that z or does it do what one effectively does when manually levelling and add the thickness of the card (0.1mm) to the z before adding the 'layer height'? Intuitively it seems to me that if you do manual levelling you are, anyway, adding 0.1mm to the layer height for the initial layer. If you then set the 'initial layer height' to, say' 0.27mm and 'layer height' to 0.2mm is the nozzle raised 0.37mm above the build plate for that first layer or 0.27mm above it or does it keep it at 0.2mm/0.3mm but squeeze out sufficient filament for an assumed nozzle height of 0.27/0.37mm. I'm sorry, this probably all sounds rather confusing (it does to me) but I'm trying to understand just what the relationship between actual nozzle height and the height settings are. I suppose I could look at the gcode but I wouldn't have a clue as to what I'd be looking for.

I have the layer height set to 0.2mm and the initial layer height set to 0.27mm (the default height for 'Fast'). Are you saying that you have the layer height set to 0.3mm and the initial layer height set to 0.2mm, ie first layer THINNER than subsequent layers? The help tip for initial layer height suggests that it should be thicker. Also, I'm a bit baffled as to why the first layer should be thicker than subsequent layers AND the initial line width should be (recommended) 120% of the standard line width. Isn't that, effectively, just increasing the width of the initial, squished, line even further? Why not make the adjustment using just one setting?

Having cleaned the glass plate as you suggested I have another print on the go at the moment which is looking considerably better (almost, but not quite, perfect). When you refer to '... not flat enough ...' are you referring to the level of the bed or the squishing of the filament (by the look of your photo you are referring to the filament). The printer auto levels the bed, is there a setting somewhere where I can effectively get the nozzle closer to the bed? Is that the layer height or initial layer height setting?

My apologies, I obviously didn't have access to the underside whilst it was printing and didn't think to take another photo once it had finished. Here is the underside (ignore the black markers, they are for a different purpose). As suggested by @geert_2 I have given the glass plate a thorough clean and am about to try again. I will also try reducing the initial layer height from 0.27mm to 0.23mm.

Yes it did. From what you are saying I think that it is very likely that the build plate needs a proper clean. I have been wiping it but nowhere nearly as thoroughly as you are suggesting. So, I will do a proper clean of the glass and play with the layer settings and see what joy I get. Thank you both for your really quick and helpful suggestions. Doug

Thank you for the quick reply. This is not a single layer print but, sadly, it is this bottom layer that will be visible and it is not practical to turn it over. I'm not using a glue stick which is probably one of the reasons that I have to have the bed at a slightly higher temperature. I can try (reluctantly!) to alter the level of the bed whilst printing but would prefer to see if I can solve the issue by other means to start with. 1. I forgot to mention in my original post that my initial layer height is 0.27mm. If I were to reduce this (to 0.2mm) and/or reduce the initial layer width do you think that would improve matters? 2. I can also try moving the print to a different part of the build plate but it is quite a large print and so there is not too much scope for moving. 3. I could raise the bed temperature. 4. I could try printing on a raft which would make for a rather rough surface but could be acceptable. Obviously I should just try each of these suggestions (and I will) but it would save time and filament (to say nothing of my sanity) if you could give me a few pointers. Thanks again, Doug

Not sure whether this is a printer problem or a Cura problem. I have an Ultimaker 3 and am using Cura 4.4.0 as the slicer. The filament I'm using is Ultimaker Sliver PLA (the one that came with the printer). My main settings are:- layer height : 0.2mm Nozzle temp : 195 C Bed temp : 65 C Initial layer Width : 120% Initial layer speed : 18mm/s Fan : Off (first layer) I'm getting what appears to be the nozzle dragging the filament as it comes out of the nozzle but just in a couple of areas (see image). I've raised both the bed temp and nozzle temp slightly (5 deg C) above normal because I was having a problem with some of the initial wall lines not sticking to the bed (as it happens, in the area of the blemishes). The second layer was laid over the blemishes without a problem but on the third layer or so there was a bit of lifting of the print off the bed although it did not look like warping (for a start it was not lifting at any of the corners). What is happening and what do I need to do to fix it? TIA