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Developed film has a bar code type of encoding for DX info. The talk about the whole roll is the ability to scan the entire thing in one go vs having to load in multiple strips.

This is a very surface level analysis like saying that the automobile was just an iterative improvement over a horse. Or a computer is just a better abacus. Fundamental research is all about diving into the weeds and finding new problems to solve. It's true that some of the "low hanging fruit" no longer exists (you won't see someone like Euler or Newton who's names pop up all over the place), but I can promise you that real gains are being made on a lower level. These small gains in fundamental research snowball into bigger advancements. As an example, the transformer architecture used by LLMs was first published in 2017.

Looks like spot melt laser powder bed fusion (L-PBF). Electron beam doesn’t make sense for something on a smaller scale like this; it wouldn't have the resolution. Spot melt is interesting. Renishaw is the only manufacturer I’m aware of that uses a pulsed laser vs continuous wave (and I’m not even sure if they’re still doing that for their newer machines). I would’ve guessed it would’ve been printed on a Farsoon since it’s in China. I just wish the images had scale bars to give a little more info.

I have both a resin and FDM printer. The FDM is hands down easier to work with than dealing with resin. FDM ABS is also a far better material than ABS-like resin. (Disclosure: I've never tried a proper industrial resin from LOCTITE or something.)

I've been very happy with my Qidi Q1 Pro. I paid about $350 pre-tax off Amazon almost a year ago (Black Friday). For me, it was the most machine for the lowest cost I could find. It almost fits your desired print volume (245 x 245 x 240), but it is fully enclosed and has a dedicated chamber heater. I have almost exclusively printed ABS at a 60 deg. C chamber temp. It runs open source Klipper firmware, but I'd imagine repairability wouldn't be the best. Best of all, I have not needed any calibration. It seems pretty spot on out of the box.

My Voron is hands down a better printer but also required significantly more investments in components and especially time.

iPhone Air 11 months ago

You're making me wish I still had access to a CMM. I wonder what the tolerances are on an iPhone.

Pi Chess Board 2 years ago

It must be. The part about minimizing the stepper motor power consumption is nonsensical. Steppers use the same current whether moving or stationary.

Most forms of metal AM require melting, which gives solidification microstructures. There are solid state (no melting) forms of metal AM though. Look up AFSD. MELD just got (part of) a billon dollar contract from the air force for it.

A line has to be drawn somewhere because this is a rabbit hole. Without going into the specifics of ASTM standards, etc., there are metal AM parts flying today in both air and space. IMO, that counts as meeting standards.

Texture (the statistical arrangement of all the crystal lattice arrangements that make up a metal) can play a role on mechanical properties, but current metal AM is more than able to meet material standards. It's good to be careful with blanket statements because the most accurate answer is usually "it depends."

I know for certain that defects in the powder layer can be fixed in binder jet by redoing the recoater. There has been talk in the research world about being able to fix errors in L-PBF but I’m not sure they’ve gone past the research stage. The big point is that you can know a part might be out of whatever your acceptance criteria might be.

I’ll bite. The capability in the US to do large castings and forgings is basically gone. Good luck getting anything with a lead time of less than a couple years. In some cases, it simply can’t be done. That’s why we’re seeing so much investment into large scale additive manufacturing.

It’s interesting how this has become such a problem again. Post WW2, the US dismantled massive, basically building size hydraulic presses in former Nazi Germany and shipped them back to the US because that was a capability we didn’t have.