A Reddit Refugee

current college student, permanent pirate, lover of all things mechanical and on wheels

moved here from lemmy.one because there are no active admins on that instance.

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Joined 1 year ago
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Cake day: December 22nd, 2023

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  • This is true. If you left it in the same environment it would eventually return to equilibrium and the net result would be the same. the key is that the plastic has a limited take up rate of atmospheric moisture. so if you dry it for a few hours, the water migrates out slowly, but then takes quite some time to migrate back in.

    generally people either print from a dryer box or dry filaments immediately before printing.


  • Humidity is relative, not absolute. Air’s carrying capacity for water increases as temperature goes up, even if the total amount of water in the air is the same.

    Air with 50%RH at 70F (eg, it has 50% of its max water content) only has about 10%RH at 120F. So if you get the filament hot, it gets dry. This can be improved with outside air circulation i guess, but it’s not necessary and usually causes extra energy use due to heating the makeup air.


  • My personal experience with a couple MMU2 on a mk3 at college is it’s garbage. You have to sit there and babysit it as it will error frequently and the filament changer seems to need endless readjustment lest it jam with a filament sprig for the 55th time today. Maybe they are better if you customize them more and don’t beat on them like college freshmen do, but… I like the idea but the ones i’ve used are not that fun.

    Be careful of what other kind of filament changers you buy though. If you want to do multi material changes involving TPU, systems like the MMU where it’s a single feed tube switcher seems to be OK, but integrated feeders like the Bambu Labs ams style will eat tpu for breakfast because it doesn’t follow guided paths very well. I think? the ERCF can feed tpu fine?





  • Even 250 is a bit low for that high of a volume. Are you running a brass nozzle or a hardened/stainless steel nozzle? Steel nozzles will require even more hotend temp due to their low conduction rates. Eg, with the stainless nozzles on a Bambu P1S, I have to run ASA at around 260/262 for higher print speeds.

    If stringing is a problem consider increasing the speed of your filament retraction (not distance) You may also want to turn off z-hop. Sounds wild I know, but it does help- by not lifting the nozzle during a rapid move, it “wipes” the nozzle clean as it moves off the part and reduces stringing. Realistically you shouldn’t use z-hop at all unless you have a part with a very small cross section that keeps falling over when the nozzle wipes across it. Which ofc, the big print I see in the photo looks like it will have zero stability problems, lol.





  • You could look into an opensource project like https://en.openscan.eu/ depending on how “small” these parts actually are.

    It requires some initial printing as well as some hardware kit purchases (provided) for the servo and controller board, but I saw a demo on youtube once that provided surprisingly good point cloud accuracy from one of these OpenScan pedestals. Good enough that you could probably generate smooth surfaces from them and make a usable part with minimal model post processing. And definitely better than you’ll ever get from a freehand smartphone/iPad scan.





  • I believe Autodesk Fusion has the ability to export multiple setups, with different processes, to a single NC gcode file. It supports both additive and subtractive machine paths.

    I’ve used it extensively for generating 5-axis machining toolpaths at work, and it’s actually quite decent to use. It’s modelling and file management is maybe a little scuffed, but definitely usable.
    I export multiple setups with multiple work offsets to a single G-code all the time. I don’t know how it might handle different machines, and different additive/subtractive processes in the same file though. That’s at the mercy of how well written the post processor is.

    It’s free for personal use but with limited functionality, however if you do end up needing the full version it’s one of the cheaper CAD subscriptions out there at $85/mo.