Re: MIT 3D printed key components of mass-spectrometer

Glen Walpert <nospam@null.void> 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:
 
<https://www.nasa.gov/humans-in-space/nasa-tests-3-d-printed-rocket-part-
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