First, thanks for all the feedback and suggestions, I’ve been going through and looking for areas to tweak. I decided, in the interim, to print a bigger model to see if I can expose the issues more, and I think I accomplished that. This is the snail from Adventure Time, and I’m mostly very happy with this print; I could have added a tree support under the lower arm, but the detail is great and the layer lines are barely visible…until you get to the raised hand a bit, and to the eye stalks. Looking at what’s going on, it looks pretty clear the layers are NOT getting enough time to cool and harden before the next starts.
I thought I had that accounted for with the following settings, but as far as I can tell, these settings are not being respected:
I would expect the printer to slow down a bit to its minimum, then when the minimum layer time is reached, it would go off to the side…but I think instead it’s hovering close to the print and not giving it space to cool down.
I don’t really want to switch slicers, but I am wondering if there’s some Cura tip to uncover what I’m doing wrong here; I’ve read a ton but I am just not understanding how to get the printer to take its time on these tiny objects.
Here is a video of it printing, it’s clearly not respecting the minimum layer time: https://photos.app.goo.gl/nhE7LjvDH9avutxd7
I’ve never used any 3d printers other than my stock ender 3, but your cooling fans don’t have any ducts to direct the air to the space right below the nozzle. They seem to be aimed mostly at the buildplate. Do you think the cooling fans are adequate in their current configuration? To me, it looks like there wouldn’t be much airflow directly below the nozzle where cooling is most necessary for good detail. Maybe, when the printer is printing smaller layers, they stay in this dead zone for a long time and don’t get adequate cooling?
If you want to try and address this, you can print fan ducts out of a heat resistant filament like PETG to better direct air right below the nozzle.
Sidenote on Cura - I was reluctant to switch slicers for a long time, but I regret not switching to prusaslicer from Cura sooner. Once I wrapped my brain around it, prusaslicer has much better profile management and more reasonable defaults than Cura does imo.
I took it off for demonstration, but usually I have this fan shroud on; or a version of this I’ve modified a bit: https://www.stlfinder.com/model/craftbot-cooling-fans-adaptor-for-barts-custom-hotend-ivdK9eKM/7784427
OK, this looks like it would work better than the bare fans but it still might not be adequate. Then again, the part cooling on my stock ender 3 isn’t supposed to be great either, but I haven’t experienced this issue when printing small details.
I opened Cura and took a look at the minimum layer time and minimum speed settings. I read the tooltips, and I was just as confused as you are until I read the comment from alkeemist. These settings might not be what you need. I’m afraid I don’t know enough to suggest anything else since I haven’t come across this issue myself.
Yea that cooling fan config is definitely not optiomal especially for small fine models.
I switced from cura to orca slicer and am never going back. Development moves much fast over here.
Omg is that the lych?
Orca Slicer
Lookup Fat Dragon Games. He’s been designing and printing derailed miniatures with FDM printers and .2mm nozzles for many years now. He’s already solved all your problems. He’s got a YouTube channel as well.
The printer won’t park the nozzle by itself to let the layer cool down, but you can trick it into doing so by adding a purge tower or somesuch. It will waste some filament, but the alternative of a g-code script to park and wait will still have issues due to oozing and losing pressure in the nozzle.
Alternatively, printing multiple parts would also allow for more time per layer.
The minimum layer time setting is just the time until the slicer tries to start slowing down, but the minimum speed will still dictate the actual layer time. And lowering minimum speed also doesn’t help as the nozzle then spends more time near the part, heating and softening previous layers.
