Comment on Need help with printer recommendations
Bluewing@lemmy.world 4 days agoPETG is tougher and in certain situations stronger than ABS. PETG also has better chemical and UV resistance. But PETG has a lower glass transition temperature, about 80C vs 100C.
Both PETG and ABS/ASA benefit from enclosed and heated chamber printers but PETG is a lot easier to print with an open bed. Both of my printers are open bed and PETG is very easy to print.
PETG is somewhat hygroscopic and will absorb moisture from the environment. Making the filament a pain to print and prone to nasty stringing. So it should be stored sealed in a dry bag/box. 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.
PETG has pretty much supplanted ABS in FDM printing. It’s often cheaper than ABS these days too. Between PLA, PETG, and TPU, those 3 filaments should cover 90%+ of all your printing needs.
KingRandomGuy@lemmy.world 3 days ago
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.
Bluewing@lemmy.world 2 days ago
An air fryer is an interesting idea if you happen to have one handy. But even dedicated filament dryers are a bit cheaper to buy, let alone a used dehydrator. And few people are using expensive engineering filament either to scratch build
KingRandomGuy@lemmy.world 1 day ago
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.
Bluewing@lemmy.world 14 hours ago
Special needs often require special materials. You have special requirements and can use those materials. When I have special needs for materials, I just walk up to my garage and machine things out of metals. I have a lathe, mill, drill press, air compressors, and welders. But, I’m that extreme outlier your momma warned you about…Not everyone has the room, knowledge and skills to do that. So, 3D printing is a very good substitute for most people.
Still, don’t dismiss those ‘basic’ filaments either. I have made more than one bending die set to bend up to 10ga/3mm steel out of the cheapest most basic PLA I can buy. It won’t last for 10,000 parts, but I know can can get a dozen bends from it. And more depending on the material and thickness of it. And no, it doesn’t take 100% infill either. 15% or 20% infill is enough. It’s all about the number of walls.
Experiment, try, fail, succeed, and most important, have fun learning.