So I tried to print just one propeller. Key word here is "tried". It was fine until 4 mm up, when the prop got out of the bed plate "ground effect" and there was less effective airflow from the fan. This was on 0.1 mm layer height. What gives? I'm printing at 12 mm/s for perimeters. Clearly there needs to be some kind of pause in between layers with the extruder off to the side. Unless I'm missing something, there's no such option in S3D (though there is in MakerBot Desktop). I can only reduce speed for layers under x seconds long, which won't help in this case. I'm thinking the thingiverse fan duct I added is not doing its job. I'll reprint with it off and see if it gets better. I'll probably get a better fan duct too. Any other ideas for how to increase cooling?
Edit: Ok, so I can add a pause in the Layer Change script, but then it'll pause for every layer. Given that the prop gets melty after just 4 mm, that's not a huge deal, but for bigger models with thin pointy tips on top, there needs to be a better solution.
Edit 2: The print without the duct was a little worse, going melty even sooner.
"Tree-branching" when printing multiple small parts
Re: "Tree-branching" when printing multiple small parts
It is what it is. If you've measured the filament diameter accurately, then the Extrusion Multiplier is the Fudge Factor required to make the actual plastic match the slicer's plans.ChrisERAU wrote:I ended up with an extrusion multiplier of 0.82. Is that normal?
Visually, they're identical, but you've just eliminated 10% of spurious plastic that would overstuff your parts: the slicer assumes that a pair of lines 0.40 mm apart will fit exactly together, with no extra plastic squeezing out around the nozzle. For extremely small parts, there's nowhere to hide the excess.The square looked the same as the 0.44 mm thick one
The wall height for that single square looks good. Now run off a full set to verify the overall platform alignment.
Printing tiny things, particularly tall tiny things with thin layers, in PLA can be a challenge, because it has such a low melting point. In some cases, printing a big sacrificial block of the same height off to one side may help; a clustered set of props may not provide enough cooling time away from the nozzle.It was fine until 4 mm up
For example: print one prop with 0.25 mm layers and a minimum 15 seconds per layer.
The secret is to keep track of what happens and be methodical about solutions: more time, more air, more motion, whatever. Don't vary things wildly, because small changes (like 10% too much plastic) will have large effects.Key word here is "tried"
And there is.for bigger models with thin pointy tips on top, there needs to be a better solution.
Several recent threads discussed Slic3r's modifier meshes and the equivalent S3D feature that let you apply different slicing parameters to different parts of the model. One example:
viewtopic.php?f=9&t=3017
Re: "Tree-branching" when printing multiple small parts
Thanks for the information! I'll definitely keep the multiple slicing parameters in mind for the future. By the way, what temperature do you run Makergear PLA at? And do you have a modified fan system and/or duct?
Re: "Tree-branching" when printing multiple small parts
Back when I was running PLA, this worked fairly well:ChrisERAU wrote:what temperature do you run Makergear PLA
http://softsolder.com/2013/07/25/makerg ... onfig-ini/
I've since switched to PETG, which works better for the brackets & doodads I build:
http://softsolder.com/2015/03/20/makerg ... -for-petg/
I've switched to 24 V power and rebuilt the brackets and suchlike, but the overall fan configuration remains pretty much stock:
http://softsolder.com/2015/03/12/makerg ... 24-v-fans/
For whatever reason, I haven't had to worry nearly as much about cooling as some of the folks around here; it's probably because I don't often build exotic parts...