[Cura 2.3 Beta Awesomeness and Some Issues]

@Yellowshark: Just wanted to thank you for this excellent post. I too have been having problems with extremely long print times and could not determine why until now. I am having great results with 2.3 beta otherwise, hats-off to the design team!

 

Ok just done my first 2.3.0 print. Happily everything ran from start to finish without any failures or real weirdos; no crashes or extrusion problems. Also the quality of the finish I thought was good, especially on first run through.

Beware! If you do not set everything to “on” with the Visibility Settings screen, you will not see what strange things Cura is doing in the background. E.G. I used a standard print and settings so I could compare 2.3.0 with 15.04.04 and Kisslicer and S3D. The first shock was that whilst it is a 27-28 minute print, Cura was estimating 42 minutes when normally for me it underestimates a small amount. Anyway I went ahead, assuming it might be acceleration or something similar;  but no it took about 42 minutes.

The first thing I did then was turn on all the Availability settings and there it was. Whilst I had asked for 30mm/s, Cura had set outer wall/skin was 15mm/s, infill was also slower, Top and Bottom were slower. Anyway it did not take me too long to get Cura back to an estimate of 26 minutes.

The top and bottom finishes came out very well; on the one sample I would say better than 15.04.4 - there were of course a variety of settings Cura had turned on without me knowing, which may have helped or been a hindrance - indeed of course some of the print speeds were slower which probably did help to enhance the finish. So I need to do some more work on that one.

On that one sample, dimensional accuracy was not good, err rather bad (same model, in theory same settings); on average 250 microns worse than Cura 15.04.4 and noticeably worse than Kisslicer, which in my recent tests, quite extensive, was not as good as Cura 15.04.4. This is even weirder given that Cura was running some of the speeds slower than I had expected.

One test does not a problem make. But I mention it at this stage only because the difference is huge. There are no curves or circles here, just rectangular geometries on the x/y axis, Maybe the developers are aware, maybe they are not.

Of course there is a bunch of settings set that I did not want, so I need to go through those carefully and retest but with the speeds being slow and  the flow being standard, I am not sure there are other settings that would have such a large impact, but I should get another test through in the next few hours.

One final point that I am hoping someone can help me with so I save some time. I selected z-hop and saw during the print than when the hop happened, there was a very small pyramid shaped piece of filament was left on the surface just exited. If you look at the final print quickly you do not see them but a closer look exposes them. I will change the retraction settings but the following will help.

Does the hop happen after, during or before the retraction?