Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Phil Hobbs Newsgroups: sci.electronics.design Subject: Re: MIT 3D printed key components of mass-spectrometer Date: Tue, 9 Apr 2024 00:38:59 -0000 (UTC) Organization: A noiseless patient Spider Lines: 84 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Tue, 09 Apr 2024 00:39:00 +0200 (CEST) Injection-Info: dont-email.me; posting-host="4b89a4a2c8e63ad0a800fc57d1116dbf"; logging-data="4016810"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+ahqDc8pYNn+e52xQzLX9F" User-Agent: NewsTap/5.5 (iPhone/iPod Touch) Cancel-Lock: sha1:Aufeoy+0BwASPW+3CENL8E6TsPA= sha1:UZ85d1OzXGaQWdt0yLUZlgiwBJY= Bytes: 4590 Glen Walpert wrote: > On Mon, 8 Apr 2024 10:49:34 -0400, Phil Hobbs wrote: > >> On 2024-04-08 10:28, John Larkin wrote: >>> On Mon, 8 Apr 2024 10:23:24 +0100, Martin Brown >>> <'''newspam'''@nonad.co.uk> wrote: >>> >>>> On 08/04/2024 05:47, Jan Panteltje wrote: >>>>> Researchers 3D print key components for a point-of-care mass >>>>> spectrometer >>>>> https://www.sciencedaily.com/releases/2024/04/240404113429.htm >>>>> pdf: >>>>> https://pubs.acs.org/doi/10.1021/jasms.3c00409 >>>>> >>>>> Massachusetts Institute of Technology Summary: >>>>> Researchers 3D printed a miniature ionizer, a key component of a mass >>>>> spectrometer. Their device could someday enable an affordable, >>>>> in-home mass spectrometer for health monitoring. >>>> >>>> It is complete nonsense. Making the hard vacuum needed for ions to >>>> move freely in mass spectrometry and sample handling to introduce the >>>> sample into the unit without losing vacuum are fundamentals that won't >>>> go away. >>>> >>>> The closest to a quick dirt cheap MS is time of flight laser ablation >>>> if your sample is a solid or can be put on one. Liquid samples are >>>> really messy and water vapour is the bane of vacuum systems. >>>> >>>> Selective ion probes offer a much better alternative for bio samples >>>> (I suppose the MIT PR department has to justify its existence >>>> somehow). >>> >>> I'd expect 3D printed stuff to outgas forever. >>> >>> 3D is super slow, too. I've heard of modestly complex parts taking days >>> to fab. The upside is that it can make things that are impossible to >>> machine or mold. >>> >> 3D resin printers are super cheap nowadays, and can do beautiful things. >> They're basically contact printers made with 8k display LCDs and UV >> LEDs, and give you nice repeatable 17-micron voxels. >> >> It doesn't matter so much that something takes a day to print, if you >> can have a shelf full of printers for $2k. >> >> Cheers >> >> Phil Hobbs > > Not all 3D printers use resin, for instance: > > to-reduce-future-sls-engine-costs/> > > This isn't the first 3D printed part in the RS-25 engine (evolved from the > SSME), just the largest so far. The printer for beach-ball size titanium > parts might cost a bit more than $2k and probably won't fit on a shelf, > but I bet those helium-tight components don't outgas much :-). > Fun. The resin printers start at around $100, though. I’m very willing to trade off the ability to print titanium for that. ;) > (I did the detail, process and tooling designs for the HP oxidizer > turbopump shaft seals for the original SSME ~1980, per proposal design and > design rules by the late Dr. Philip Stein, PhD in metallurgy from MIT 1927 > IIRC. LOX on one side, hot H2 and steam on the other, lube oil mist and > bearings in between, ~28k RPM shaft with play and significant thermal > movement, engines shut down automatically if either seal fails. So I > check now and then to make sure none of my parts have failed :-). An excellent idea. I do the same with my body parts. ;) > > Glen > Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics