In your comparisons I could still see quite the difference when outer speed is low and inner is high. What if those problems could be avoided by printing the outer wall slowly first and then printing the inner walls fast? Should avoid deformation that is being caused by the fast inner walls. In theory the overhangs should be worse, but I think it is worth a try
Yes, printing the outer walls first will make the most consistent surface look, but your retraction must be on point for a nice start to the outer wall. I usually print the outer wall first on objects that don't have higher than 45-degree overhangs and are smaller-medium size. But it is a topic on its own as I experienced not the ugly overhangs but some random strands on higher overhang corners. Maybe the corners curl upwards, and the start of extrusion starts in mid-air? I haven't deep-dived into this topic so it is only a speculation.
I recall Slice sells boron nitrid paste for mounting the nozzle. It's a thermal compound and anti seize. But I'm too cheap for $10 paste so i bought HY410 for $1.60 (10g) instead. I dont know if it does anything for thermal transfer but i didn't get it to smell or smoke, which is already nicer than copper grease anti seize for brakes. It's rated to a mystery temperature of anywhere between 260 and 300°C depending on whom you ask, but that's way better than standard PC thermal pastes which can start smoking at 150°C. Not that you should use it in your PC, no, it's clearly not tuned for that. Anyway thinking perhaps a filler of that ilk can bridge the... Pardon me, gap, between better fitted nozzles and cheap generic ones.
Are you printing outer walls first or inner first? In the latter case, the outer wall will conform to and copy any artifacts from the inner wall. In order to do crazy fast (high accel that is; speed is irrelevant) inner walls with no harm to outer surface quality and dimensional accuracy, you need outer walls first and sufficient cooling to have them fully hardened before the inner walls are laid.
I am printing the inner walls first, like probably 99% of the people would do. The video is exactly about how much inner walls transfer those artifacts to the outer ones. And yes, I understand that, but those conditions are not very realistic and wouldn't work that well for smaller models or ones with overhangs.
@@PrintingPerspective They really do work well. It's what I've been doing for the past 2+ years. Outer first gives better overhangs too in my experience, but it's really unforgiving if you have bad restarts after retraction (or after unretracted internal travel) which seems to be why slicers don't do it by default (on the Cura bug tracker you can see where they reverted the Cura 5 change to outer first back to inner first because of folks experiencing this class of problem). I guess what I'm trying to say here is not to argue with you but to point out that the "inner walls crazy fast" approach to fast prints only works well (at least above a certain benefit threshold) when you meet other preconditions to use it well. Whether those make sense to do is something folks have to decide for themselves.
@@PrintingPerspective My theory is that without a good foundation below to bond to, surface tension (or whatever weird internal forces the plastic experiences) pulls the outer wall to the inner one and makes it warp/curl worse than it otherwise would, whereas without an inner wall it has nothing but the partial contact with the layer below to cling to. My printer is an Ender 3 in frame and motion system but the extruder and cooling systems are completely different and hotend rather upgraded. You can see it in my videos.
@@daliasprints9798 That explanation might make sense, but would then also predict that overhangs > 45° (for a layer-height at 50% of the nozzle-diameter) would droop more if you print outer walls first (as you do not have the inner wall pulling in on that overhanging outer wall and the wall below it has insufficient overlap and itself will already have sagged) and that would normally cause significantly worse overhangs.
And if you print the outer wall at 25-30mm/s then I bet there will be no difference compared to when printing both at the same lower speed. But that is only my guess, there are so many different printers with different setups that it is impossible to say with complete facts. That is why I didn't cover the part of best speeds for the inner wall. :)
I really your detailed explanation videos! I see the layer lines are not really perfect on most printers, also on your prints they are visible under bad lighting. Why do you think these horizontal layer lines are occuring? Im trying really hard to get away of them on my prints.
@@PrintingPerspective cheers, thank you! Love your videos, they are thourough and go in depth on several areas. As a suggestion, it would be interesting to see a video on whether bridging at high speed is better, many people bridge very slowly but I always wondered whether that would cause the plastic to droop more
So the reason most people print bridging slowly is that the fan has more time to cool down the filament. It basically hardens in the air and doesn't stretch that much. That is the theory behind that. And if you would print it fast, the plastic would just stretch because it comes out of the extruder as a viscous mass. That is also a theory behind that. But honestly, I am kinda down to do a quick test :D And if I do I will make a post on Twitter and on the RU-vid Community page on my channel.
Ooh so you’re saying I can maintain my outer wall print speed at a nice cool 200mm/s but speed up even more on the inside to 500+ without much quality decrease hmmm
Yes, you should just try a few test prints to know for sure with your setup. You can get an even better print surface when printing outer walls first with sufficient cooling. But that doesn't work well on all the models.
