Hacker News: fbd_0100

New comment by fbd_0100 in "How SpaceX streamlined the Raptor engine"

fbd_0100 — Fri, 18 Sep 2026 20:37:30 +0000

I can't speak to the proximal cause of the roughness and porosity, but if you've ever held a raw printed aluminum part in your hand it is immediately apparent. That said there are processes to deal with porosity like Hot Isostatic Pressure (HIP) treatment that basically crushes all the voids with immense pressure. This does come at the cost of dimensional accuracy though (HIP will compress the part somewhat).

Similarly, annealing a 3D-print to relieve residual stress does work, but it also will cause warping as those stresses are relieved. Again, sacrificing dimensional accuracy. Frontier AM companies have ways to compensate for all of these effects but it's a trial and error process for each part essentially.

At this point you're now stacking multiple processes on each other just to try to get to near-billet properties. Calibration Trials > Print > HIP > Anneal > Machine. The cost adds up quickly. It can be justified especially in non-fatigue-critical applications but it's no free lunch

New comment by fbd_0100 in "How SpaceX streamlined the Raptor engine"

fbd_0100 — Fri, 18 Sep 2026 20:17:41 +0000

crack growth in metals is driven by microscopic flaws that cause high-intensity but very localized stress concentrations. Over time even low stress levels cause these flaws to grow to the point where they start causing strength problems. Even in traditional aluminum machined parts, increased surface roughness can have a large impact on fatigue life.

3D printed parts are chock-full of these microscopic flaws, porosity, and have horrible surface roughness (most parts you see in production are post-machined to improve the finish). Additionally, the repeated heating-cooling of the layers as they are deposited builds up residual stress in the part. All just due to the nature of how they are manufactured.

New comment by fbd_0100 in "How SpaceX streamlined the Raptor engine"

fbd_0100 — Fri, 18 Sep 2026 20:05:09 +0000

It has mild strength downsides, but very severe fatigue and damage tolerance downsides. Knowing this, it makes sense that 3d printing tech would make headway in space industry but not (yet) in aviation

New comment by fbd_0100 in "Can we stop with the uptime percentages?"

fbd_0100 — Wed, 16 Sep 2026 17:19:02 +0000

Just two weeks ago protonmail had a massive outage related to data center cooling failure.

New comment by fbd_0100 in "Global bond yields hit 2008 highs, raising stakes for big borrowers"

fbd_0100 — Tue, 15 Sep 2026 16:37:16 +0000

you may have the causality reversed. perhaps treasury yields are rising because bond investors would rather fund data center build out than buy 10yr notes

New comment by fbd_0100 in "PageRank explained"

fbd_0100 — Wed, 26 Aug 2026 16:00:58 +0000

His name may have influenced him to make his career from ranking pages

https://en.wikipedia.org/wiki/Nominative_determinism

New comment by fbd_0100 in "Spotify just hit 300M Premium subscribers"

fbd_0100 — Tue, 04 Aug 2026 16:49:30 +0000

same. long time user, haven't really noticed any major changes

Whisper's JetFoil Promises Near-VTOL at Half the Thrust

fbd_0100 — Tue, 02 Jun 2026 20:46:32 +0000

Article URL: https://www.ainonline.com/aviation-news/futureflight/2026-06-02/whispers-jetfoil-promises-near-vtol-half-thrust

Comments URL: https://news.ycombinator.com/item?id=48376043

Points: 3

# Comments: 0

New comment by fbd_0100 in "Bitwarden scrubs 'Always free' and 'Inclusion' values from its site"

fbd_0100 — Fri, 15 May 2026 16:14:03 +0000

Well, it was nice while it lasted.

New comment by fbd_0100 in "If America's so rich, how'd it get so sad?"

fbd_0100 — Thu, 23 Apr 2026 19:40:24 +0000

just turned 32 and I feel this as well. I feel into a deep depression shortly after graduating for this exact reason; mourning the loss of that regular contact with similar-age, similar-interest people as they all moved across the country to start their careers. Similar thing happened a few years later when I was internally transferred to another group at work with no people my age. It's never been the same since.

I've always scoffed at paying for those "activity groups" (what kind of loser would pay for friends?), but recently I've started reconsidering.

New comment by fbd_0100 in "Ask HN: Any interesting niche hobbies?"

fbd_0100 — Wed, 08 Apr 2026 21:23:35 +0000

what FPV drones do you recommend for someone just getting into it?

New comment by fbd_0100 in "Why are my headphones buzzing whenever I run my game?"

fbd_0100 — Wed, 03 Dec 2025 16:01:26 +0000

why do you say that? I used a Schiit Bifrost for many years without issue

New comment by fbd_0100 in "4000 gone: Inside NASA's brain drain"

fbd_0100 — Thu, 16 Oct 2025 21:57:52 +0000

There's a thriving community of aerospace startups in the US right now that are eager to snatch these NASA folks up. It won't be the right move for all of them, and it's unfortunate to get displaced from a comfortable, prestigious job like that, but I strongly believe a lot of these people will go on to do great things in industry, and potentially have a far greater impact on aerospace than they ever could at NASA.

Not saying I agree with the cuts, just pointing out there may be a silver lining.

New comment by fbd_0100 in "AWS CEO says using AI to replace junior staff is 'Dumbest thing I've ever heard'"

fbd_0100 — Thu, 21 Aug 2025 14:39:43 +0000

Progress on airplanes is often tracked by # of engineering drawings released, which means that 1000s of little clips, brackets, fittings, etc. can sometimes misrepresent the amount of engineering work that has taken place compared to preparing a giant monolithic bulkhead or spar for release. I have actually proposed measuring progress by part weight instead of count to my PMs for this reason

New comment by fbd_0100 in "Ask HN: How do you tune your personality to get better at interviews?"

fbd_0100 — Thu, 14 Aug 2025 16:11:06 +0000

I recently started a new job (big upgrade from my last gig), and after onboarding, one of my interviewers told me that a major factor in him recommending me for hiring is that I "looked bored and ready to move on" during the technical interview. I'm not sure if trying to look bored is a winning strategy in general, but there is my personal anecdote.

New comment by fbd_0100 in "How Boom uses software to accelerate hardware development"

fbd_0100 — Tue, 12 Aug 2025 14:24:11 +0000

Agree on most points. However as someone who has worked on new aircraft I can tell you that friction/mis-communication/finger-pointing between airframe and powerplant manufacturer is a huge issue. There is a common saying in the industry, that you should never design a new airframe and a new powerplant at the same time. Each new aircraft certification program should be one or the other

New comment by fbd_0100 in "How Boom uses software to accelerate hardware development"

fbd_0100 — Tue, 12 Aug 2025 14:19:52 +0000

I work in this space. Most likely it is a huge conglomeration of commercial CFD, FEA, and CAD softwares, custom in-house codes, and empirical aircraft design curves all stitched together with some python.