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Cake day: June 15th, 2023

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  • You’re correct about all of this, but it’s way easier to press print than machine a part from stock. I do some machining as well (I don’t own the machines, but I’m trained on the mill, lathe, and waterjet in our shop). So most of the time if I can get away with a 3d printed part, it’s worth it for the time savings alone. Plus sometimes the easiest or optimal geometry to design is not something that can be machined, but can be printed.

    It’s specific circumstances where the basic filaments fall short, like creep and heat resistance, irrespective of print parameters. ASA and PET-CF work well in most of these spots, so I don’t do anything more exotic.



  • That’s all fair! For myself I use a lot of PET-CF, especially annealed. For some applications you can get away with the stiffness and the creep resistance provided by annealed PET-CF rather than needing a machined part, so for me an air fryer or equivalent is a must (for both drying and annealing). I build stuff for astrophotography, so having a material that is heavily resistant to creep and is also stiff is a must.

    I’ll note that for PETG, if your print is under nontrivial load, it will probably start to deform well below the 80C mark. Continuous use I believe is about 70C. Though because PETG is so inexpensive, you can always just reprint as long as assembly isn’t too difficult.

    You’re right that PLA, PETG, and TPU are like 90% of anyone’s needs though.


  • Having a way to dry filament is a good idea. You can do so with a cheap food dehydrator or a dedicated filament dry for the purpose.

    My favorite way is an air fryer, as it can actually hit the temperatures needed for certain engineering filaments (ASA-CF, PET-CF, PPS-CF) and the forced air combined with the fact that they aren’t sealed tends to be more effective than the spoolholding dryers. I then print from a dry box made from cereal boxes with molecular sieves. This is overkill if you are just printing standard filaments though (PLA, PETG, TPU, etc.)

    I’ll add that there are still fairly common situations when you’ll want ABS/ASA: If you’re building something with stepper motors (say parts for a printer), ABS/ASA’s higher temperature resistance means you can push more current through your motors without deforming the print where the motor is mounted. This is of course especially helpful if you’re putting parts into a heated chamber, where PETG will likely start to deform under prolonged use at 60C+ temperatures. ABS/ASA are also more rigid, so they’re better for high speed printer parts. Finally, if you’re putting something in a car in a hot environment, PETG will not really hold up, but ASA will.


  • W.r.t your spool question, ABS is still a great material choice for a lot of applications since it has pretty well rounded properties. Reasonably strong, reasonably rigid (but not brittle), reasonably creep resistant, and fairly temperature resistant (probably the cheapest filament that can withstand a hot car). It’s generally a bit tricky to print though. You need an enclosed printer for good results (much better layer adhesion and less risk of warping and cracking) and it’ll emit styrene fumes which you don’t want to be breathing. I always put my printer outdoors if I’m printing ABS or its replacement in ASA.

    If you don’t care about that high temperature resistance and just want decent impact strength, then PETG is an acceptable alternative. It’s pretty cheap, easy to print, but is a little more flexible than ABS. It has decent creep resistance as well, unlike PLA.


  • Yeah, it’s absolutely not at the level of beginner and user-friendliness that you’d expect out of a professional CAD package yet, so it’s understandable you had a rough experience. I think we’re all hoping that FreeCAD will eventually see a similar level of improvement that Blender and KiCAD got in this area. Both of them were originally much worse in terms of usability, but after enough effort (and investment from major players like CERN in the case of KiCAD and community members), they ended up being really competitive packages.



  • I wouldn’t necessarily say it’s dogshit as I’ve been enjoying the beta releases. What I will say though is that the workflow feels different enough compared to every other commercial CAD program I’ve tried (solidworks, fusion, inventor) that it required me to effectively re-learn the software rather than jump right in. Pretty much every other CAD program didn’t have this problem, in part because they’re more forgiving when you violate best practices.

    FreeCAD is much more rigid in comparison. If you follow its best practices, it works wonderfully, but when I came from another CAD program my previous experience kept making me run into issues.





  • Unfortunately proprietary professional software suites are still usually better than their FOSS counterparts. For instance Altium Designer vs KiCAD for ECAD, and Solidworks vs FreeCAD. That’s not to say the open source tools are bad. I use them myself all the time. But the proprietary tools usually are more robust (for instance, it is fairly easy to break models in FreeCAD if you aren’t careful) and have better workflows for creating really complex designs.

    I’ll also add that Lightroom is still better than Darktable and RawTherapee for me. Both of the open source options are still good, but Lightroom has better denoising in my experience. It also is better at supporting new cameras and lenses compared to the open source options.

    With time I’m sure the open source solutions will improve and catch up to the proprietary ones. KiCAD and FreeCAD are already good enough for my needs, but that may not have been true if I were working on very complex projects.


  • Cute cat! Nevermore and Bentobox are two super popular ones.

    Since you’re running an E3 V2, first make sure you’ve replaced the hotend with an all-metal design. The stock hotend has the PTFE tube routed all the way into the hotend, which is fine for low temp materials like PLA, but can result in off-gassing at higher temperatures such as those used by ASA and some variants of PETG. The PTFE particles are almost certainly not good to breathe in during the long term, and can even be deadly to certain animals such as birds at small quantities.



  • Yeah, I agree. In the photo I didn’t see an enclosure so I said PETG is fine for this application. With an enclosure you’d really want to use ABS/ASA, though PETG could work in a pinch.

    I also agree that an enclosure (combined with a filter) is a good idea. I think people tend to undersell the potential dangers from 3D printing, especially for people with animals in the home.




  • KingRandomGuy@lemmy.worldto3DPrinting@lemmy.worldEnder 3 V2 damage?
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    6 months ago

    PETG will almost certainly be fine. Just use lots of walls (6 walls, maybe 30% infill). PETG’s heat resistance is more than good enough for a non-enclosed printer. Prusa has used PETG for their printer parts for a very long time without issues.

    Heat isn’t the issue to worry about IMO. The bigger issue is creep/cold flowing, which is permanent deformation that results even from relatively light, sustained loads. PLA has very poor creep resistance unless annealed, but PETG is a quite a bit better. ABS/ASA would be even better but they’re much more of a headache to print.


  • It really depends on what you’re looking for. Are you just looking to learn how to print new materials, or do you have specific requirements for a project?

    If it’s the former, I’d say the easiest thing to try is PETG. It prints pretty reasonably on most printers though has stringing issues. It has different mechanical properties that make it suitable for other applications (for example, better temperature resistance and impact strength). It’ll be much less frustrating than trying to dial in ABS for the first time.

    ABS and TPU are both a pretty large step up in difficulty, but are quite good for functional parts. If you insist on learning one of these, pick whichever one fits with your projects better. For ABS you’ll want an enclosure and a well ventilated room (IMO I wouldn’t be in the same room as the printer) as it emits harmful chemicals during printing.